Make sure you have plenty of popcorn handy, as this is quite a tale!
The bike in question had a 944 Ferracci kit fitted, by a dealer in OK, a couple of years ago. At first try - they (somehow?)fitted a 4v top end to it, and couldn't figure out where to run the water hoses :o
So, they had to start all over again, and install the correct 2v conversion. The owner says the bike never ran correctly, and after entrusting further work to a 'recognized' mechanic, was given it back (with a hefty bill) and told to 'Just ride it, it will be OK'. So, on his first ride, it went on to one cylinder 2 miles from home, and he had a long/hot push. It then got parked for over a year, until he brought it to me. It has Keihin FCR41 flat slides, and V&H slip ons, and looks nice.
1/ First job was getting the carbs ultrasonically cleaned and remounted/synced. Also found the gas tank dirty, and both fuel pump & low fuel sensor not working (both replaced and tank cleaned, but new fuel filter put outside tank)That done - it again ran on 2 cylinders, but on blipping the throttle (static on lift) - there was a definite 'breakup' starting around 5-6Krpm.
2/ HD ground cable fitted, directly from battery to engine, new starter solenoid/battery fitted
3/ Sidecase pulled and air gap re-set (both incorrect) on ign pick ups, timing backed off a couple of degrees (as per most thoughts about high compression and modern pump gas)
4/ On road test, at around 5krpm, felt like you had hit the kill switch -- back on the lift.
5/ Spark was weak, so Nology coils/aftermarket ignition modules/Taylor Spiro Pro wires fitted, along with NGK DPR8EIX plugs (gapped at 0.035") fitted. On road test - no different.
6/ Carbs pulled and float levels checked (9mm). Found jetting was - ELV needle in 4, 65 pilots, 200 main airs, 185 mains. Talked to tech at Sudco, who informed me the 'spec' jetting on the FCR41 Duals was EMT needle in 3, 60 pilots, 200 main airs and 155 mains, which concurs with Chris K's base settings (Ca Cycleworks)
6/ Base jetting installed - but NO difference on road test
7/ Needles raised to 5, but no difference - still feels like you've hit a decompressor at around 5krpm.
So - unless I'm completely missing something, I seem to have addressed most of the likely 'suspects'?
Just about to check cam belt timing, and valve adjustment, as I'm skeptical about what happened when the Dealer installed the wrong kit. Makes sense (at least to me!) that they had 'egg on their faces' after the 'boo boo', and maybe just rushed putting it back together, and 'missed' something.
The other 'anomoly', is who actually changed the jetting from suggested base settings, and what they were 'chasing'/trying to iron out?
Well, I hope to hear back from anyone ever having even remotely the same problem!
Thanks for your time - I hope the popcorn held up!!
Brid.
PS -- Forgot to mention the engine has a tad over 150psi static compression, on both cylinders
Wow. :o
What a shame.
That combination should normally be a really satisfying street motor.
Do you mean cranking compression throttle held wide open? I would want to see more than 150 psi which is closer to stock pistons. I've seen around 180-200+ psi cranking compression from 11:1 pistons, both 904 and 944.
Curious about the aftrrmarket ignition. Is it programmable or just simple ignitors?
Intake. Open or stock airbox? Open airbox then 165 main jets. 185 is drowning in fuel. Dont know why they tried super rich main jets and those needles. EMT is base setting as you say, I will have to check the charts for ELV to see where they were going.
If it has an open airbox or K&N barrel filters 155 is way too lean as much as 185 is drowning.
How did they fit a 4V 'top-end' into an SS frame? The 2V barely fits!
Also, I'll be watching this thread...
Quote from: koko64 on June 20, 2016, 12:17:59 PM
Wow. :o
What a shame.
That combination should normally be a really satisfying street motor.
Do you mean cranking compression throttle held wide open? I would want to see more than 150 psi which is closer to stock pistons. I've seen around 180-200+ psi cranking compression from 11:1 pistons, both 904 and 944.
Curious about the aftrrmarket ignition. Is it programmable or just simple ignitors?
Intake. Open or stock airbox? Open airbox then 165 main jets. 185 is drowning in fuel. Dont know why they tried super rich main jets and those needles. EMT is base setting as you say, I will have to check the charts for ELV to see where they were going.
If it has an open airbox or K&N barrel filters 155 is way too lean as much as 185 is drowning.
Koko64 - The compression was just a quick check to see if both cylinders were the same. On cranking, it sounded like the ignition timing was way advanced - but a lot of that was a bad battery, which 'sank' to only 4 or 5 volts on starting. Whilst checking the 2nd cylinder, the starter solenoid decided to stick, so it was mad panic to get the battery cable off! So - no w/open readings taken, but I really don't think lack of compression is a serious issue. The igniters are not programmable. Airbox is stock. As mentioned, both Sudco & Ca Cycleworks gave the same base jetting, for the 944 motor. As per them, slow air screw is at 1-1/2 turns out and mixture at 3/4 turn out.
Duck - Stew -- I have NO idea how they managed it, but that's the story from the owner, who's father had to deal with cussing them out!
Maybe Eric will chime in on his experiences with the appropriateness of the base jetting of Keihins...on any version of the 900 motor.
900SS with hi-comps, FCR41's, and open airbox
EMS needles, clip on 3rd
165 mains
50 pilots
Main air jet 200
slow air screw 1 3/4 turns
Dunno what the plan was there with the ELV needles.
I suspect that was a hail mary.
Just to make sure we're on the same page, clip position 1 is furthest from the taper.
I've found that 'baseline' setting of air screw and fuel screw is nearly meaningless.
+/- 1/2 turn on the air screw is a big change.
All that said...
I think there's an ignition problem.
Have you put a timing light on it?
Perhaps the flywheel is off a tooth.
It has a stock airbox. Is that unmolested with the lid intact? If so start with the SUDCO 155 mains base line.
I was wondering about the ignition being aftermarket. As has been suggested it may be set up incorrectly or something associated with it is.
Better check everything after what has happened, you'll probably keep finding stuff.
Quote from: Speeddog on June 20, 2016, 02:58:24 PM
900SS with hi-comps, FCR41's, and open airbox
EMS needles, clip on 3rd
165 mains
50 pilots
Main air jet 200
slow air screw 1 3/4 turns
Dunno what the plan was there with the ELV needles.
I suspect that was a hail mary.
Just to make sure we're on the same page, clip position 1 is furthest from the taper.
I've found that 'baseline' setting of air screw and fuel screw is nearly meaningless.
+/- 1/2 turn on the air screw is a big change.
All that said...
I think there's an ignition problem.
Have you put a timing light on it?
Perhaps the flywheel is off a tooth.
Just spent a couple of hours going through electrical connections, remaking grounds and slathering everything with (more!) dielectric grease. Fired it up and put the strobe on it (again!) and it's doing what it's supposed to down there, so - the flywheel can't be off a tooth. As mentioned, the airbox is stock - and, can Sudco/CaCycleworks be that far off with suggested 'hard' jetting? It runs fine with small throttle blips, falls back to idle quickly (around 1200rpm) so - the pilot circuits are clearly pretty darned close. But - as soon as you try and rev it over around 5/6K, it breaks up horribly.
What brand ignition boxes?
Procom PE-C-MD900-A boxes. An odd thought, but maybe someone switched the pick up coil wires at the igniter box plugs? LH box in Horizontal cylinder, and wires in plug are L-White and R-Red. Vertical box is L-Black and R-Yellow. The Haynes book I have (91 to 96) doesn't show any colours on the pick up wires in the wiring diagram, but does say Horizontall cyl is the Red/White pair & Black/Yellow for the Vertical. Anyone have a running bike with same colour coding?
BTW - Airbox is stock - not molested!!
AND - please remember, it had this problem with stock coils/wires and the Kokusan boxes, but the spark was weak.
[img=https://s31.postimg.org/f9f6tgax3/001.jpg] (https://postimg.org/image/f9f6tgax3/)
Sorry...I have to chuckle. [evil]
Quote from: ducpainter on June 20, 2016, 06:41:45 PM
Sorry...I have to chuckle. [evil]
Did I miss something?
Quote from: Brid on June 20, 2016, 07:05:37 PM
Did I miss something?
The completely OEM airbox lid and all this talk of upgrades made me laugh.
Did you miss something? ;D
Quote from: ducpainter on June 20, 2016, 07:15:03 PM
The completely OEM airbox lid and all this talk of upgrades made me laugh.
Did you miss something? ;D
I'm still a bit in the dark here, as I've tried running it without the airbox lid - and it makes no difference. If changing to K&N pods would be an epiphany, we'd be there in a shot, but nobody so far has sworn it will cure the problem. Also, please remember - I 'inherited' this job, after several more folks had their grubby fingers in there, and I'm just trying to be humble and ask folks with better knowledge than me on this particular issue.
Yeah I feel for you as there have been a few cooks in the kitchen before you. I pick up jobs like that all the time after others have well and truly make the beast with two backsed the bike. It's normal business now and I'm used to it.
Some thoughts.
Check the ignition wiring and check which way you went with the pick ups. It sounds like an unwitting rev limiter from some ignition issue. As if it is not advancing.
Or.
Fuel pump ok? Fuel pressure too much overwhelming the float needles? Running the return line with the pump?
What do the plugs look like after all that fuel from the 60 slow jets and 185 main jets? They may be breaking down up higher in the rev range. The 185s would drown it whether the airbox was open or closed.
Don't do pods as a solution, with an unported motor the result is similar to an open airbox. A whole lotta other tuning there. Stay with the closed airbox and SUDCO tuning (although I have often found the 60 slow jets too rich on 41s), or go open airbox and speeddogs baseline which I also use with some variations on needles depending on how much I mess with the airbox.
Quote from: koko64 on June 20, 2016, 08:39:18 PM
Some thoughts.
Check the ignition wiring and check which way you went with the pick ups. It sounds like an unwitting rev limiter from some ignition issue. As if it is not advancing.
Or.
Fuel pump ok? Fuel pressure too much overwhelming the float needles? Running the return line with the pump?
What do the plugs look like after all that fuel from the 60 slow jets and 185 main jets? They may be breaking down up higher in the rev range. The 185s would drown it whether the airbox was open or closed.
Don't do pods as a solution, with an unported motor the result is similar to an open airbox. A whole lotta other tuning there. Stay with the closed airbox and SUDCO tuning (although I have often found the 60 slow jets too rich on 41s), or go open airbox and speeddogs baseline which I also use with some variations on needles depending on how much I mess with the airbox.
I re-checked the ign wiring today, and everything seems fine. Strobe shows that it is barely getting to full advance, so my 2 degree retard (an educated guess!) looks OK. Plugs were new before last quick road test (which only lasts a couple of minutes before the problem shows up) so, haven't checked them. As mentioned - new fuel pump, but I've also tried it with just gravity feed -- no difference. Using the return line, which is working fine.
IIRC about 0.7 of a deg advance per 1mm of pick up being slid back. I would go for 3 deg advance so 4-5mm. Also that is assuming the ignition boxes you are using have the stock advance map in them. Some boxes already have a retarded map for hi comp application for example some DP boxes come set up for various states of tune. That could mean the ignition is too held back to rev. Maybe. You might have some testing to do there if nothing else is wrong.
Re the amount of adjustment of the pick ups, Brad Black and my math teacher wife helped me with that one. ;D How much you slide em back?
Someone might recognize those boxes and what's in 'em.
Nowdays I would rather use an adjustable Ignition system like the Ignitech and leave the pick ups alone. Don't lose your way with them. Did you mark where they originally were? Where is the idle advance in the window?
Idle advance is just a tad to the right of the dot, and same with full advance. I bought the boxes off an E-Bay seller, who assured me they had the stock advance curve, and would be fine using the Nology coils. Again - this problem arose with the stock Kokusan boxes (which I changed due to weak spark) so, it seems doubtful the Procom ones are at fault?
I don't know the numbers on them and what maps are inside.
If it had stock boxes before and did not ping then the pick ups may have already been slid back. How much who knows? A pic of the window at idle and full advance will quell my concern or confirm it. That could be an issue if the same people also slapped a Desmoquattro head on it. [bang]
LT Snyder doesn't like the Nology coils, something to do with incompatibility issues but I have no FHE.
I'm wondering if the voltage at the coils may not be enough to fully charge them beyond 5k rpm.
Which Nology coils do you have?
SD is a Ducati specialist.^
Got an in line spark tester? Spark drop off at 5k?
Quote from: Speeddog on June 20, 2016, 09:29:42 PM
I'm wondering if the voltage at the coils may not be enough to fully charge them beyond 5k rpm.
Which Nology coils do you have?
Not in the shop (11.37pm here!) so, can't answer that, however - I specifically asked both suppliers (boxes & coils) about compatibility, and can only hope they were honest??
Quote from: koko64 on June 20, 2016, 09:37:26 PM
SD is a Ducati specialist.^
Got an in line spark tester? Spark drop off at 5k?
Yes - I have an inline tester, and will try that tomorrow
Quote from: Brid on June 20, 2016, 07:26:18 PM
I'm still a bit in the dark here, as I've tried running it without the airbox lid - and it makes no difference. If changing to K&N pods would be an epiphany, we'd be there in a shot, but nobody so far has sworn it will cure the problem. Also, please remember - I 'inherited' this job, after several more folks had their grubby fingers in there, and I'm just trying to be humble and ask folks with better knowledge than me on this particular issue.
I wasn't laughing at
you. Sorry if that's what you thought.
It was just the situation I find amusing. Whoever built that thing with FCR's and a stock airbox with that jetting is capable of any crime. I wish there was an easy answer, but as you've begun to dig into it, you've already figured out there isn't.
Quote from: Speeddog on June 20, 2016, 09:29:42 PM
I'm wondering if the voltage at the coils may not be enough to fully charge them beyond 5k rpm.
Which Nology coils do you have?
Hey Speeddog, coils are PFC-30-S, 3 ohm. I just ran it with an inline spark tester, and it never misses a beat. In fact, looks like it gets better as revs increase. BTW - when you said 'open airbox' in an earlier post (with jetting suggestions) how open do you mean? Heard of folks cutting the top out - but still running a filter, using K&N RU1750 pods etc. We're definitely not shy about trying anything, #1 - to cure the problem, and #2 - to optimize any power gain from the 944 kit and FCR's.
A bit of an update! I went back into the timing side case to (again) check everything was good with the pick up coils, and found the threads were 'popped' on the top coil mounting bracket (front one) So, although the bottom one was good, the bracket could vibrate with the engine running. I imagine it just caused a 'variable' air gap on the front pick up coil? A quick helicoil job, and air gaps again set at 0.024", and she runs again. Too late to road test it tonight, as I'm going to get dinner before 11pm for a change. Fingers crossed for tomorrow ;)
[thumbsup]
Pity you didn't take a pic of where the pick ups were adjusted on the case brackets. Hopefully that does the job. They are prone to being over torqued being so delicate.
If you want to get the most out of these mods once its all sorted ignition wise try opening the airbox lid (top of the lid cut off at least half removed, but you can just leave enough to hold the filter down) and for an easy baseline 165 main jets, 50 slow jets, and using the EMT needle supplied start with notch 4 or 5 and play with that to get a good balance between smoothness and economy and acceleration. If you can get the needles for a good price just install speeddogs baseline setting. Depending on the state of the bikes heads from the factory and local weather you may change the slow jet a size each way.
Cheers.
Quote from: koko64 on June 21, 2016, 06:30:22 PM
[thumbsup]
Pity you didn't take a pic of where the pick ups were adjusted on the case brackets. Hopefully that does the job. They are prone to being over torqued being so delicate.
If you want to get the most out of these mods once its all sorted ignition wise try opening the airbox lid (top of the lid cut off at least half removed, but you can just leave enough to hold the filter down) and for an easy baseline 165 main jets, 50 slow jets, and using the EMT needle supplied start with notch 4 or 5 and play with that to get a good balance between smoothness and economy and acceleration. If you can get the needles for a good price just install speeddogs baseline setting. Depending on the state of the bikes heads from the factory and local weather you may change the slow jet a size each way.
Cheers.
Hey Koko64, First thing is to pray I found the worst of the problem! I strobed it after the repair, and it's exactly where it was, about 2 degrees retarded. One thing I noticed is, it jumps to full advance pretty quickly, around 3krpm or so. I realize the retard is just for starting, and occasionally work on bikes with no dynamic advance (RD400 for one) Main bugbear is having to remove all the coils/igniter assy/airbox, just to get to the carbs, which makes a needle clip change over an hours work, and a pilot jet around 90 minutes or so. Still, after all I've done on the bike, I guess it deserves jetting correctly [roll]
Thanks for all your thoughts so far,and let's pray it wants to play ball tomorrow!
The Kokusan boxes have a pretty crude advance curve. The term curve is being generous, more like an angle graph. They hit max advance too early with high comp but understandable with the stock 9:1ish pistons. Built down to a price I guess. :P
Fair enough. Just get it running ok and think about performance tuning later after all those late nights. I separate the battery box from the airbox for easier servicing. You can make a little quick release bracket that connects them for support. Since I use lithium batteries I just cut away the bridge that joins them giving me access to the tops of the FCRs without moving anything except maybe the battery.
(http://i1024.photobucket.com/albums/y304/tonykokonis/2013-10-30%2021.39.41_zpss5peah0d.jpg)
Ignore the airbox mod (only helps on more modified, ported motors).
This is an example of separating the airbox from the battery. I trimmed the airbox area above the tops of the carbs with a dremel to give good access to the carb tops making needle changes easy. Main jets are easy via the big drain bolt and slow jets just mean removing the bowls with the carbs in place. Next time the lot comes off you can do this and subsequent needle changes are easy as is synching with a manometer.
I'll certainly be giving any updates on the progress. Strange how the job started so innocently - make run & a set of tyres, then morphed into chasing all sorts of things. In all though, we've addressed electrical problems which were just about to manifest themselves. The stock coils were right at the raggy end of the specs, and the spark was suffering. Fitting new igniters was then more a necessity than not, as there's no test for them I could find for the stock Kokusan's. I road raced for many years, and used Taylor Spiro Pro plug wires on all the bikes I built/raced, and never had a problem, and - they look quite the part on the red SS! It seems just when you think you've seen it all (I've been at this for around 45yrs) something new turns up - like in this case. I guess it makes life a lot more interesting!! [beer]
Cheers [beer]
Fuel starvation?
What do the plugs say when you hit the "stop"?
Semicollapsed pump diaphragm can cause this type of behaviour.
Does it accept full throttle up to 5k?
Quote from: greenmonster on June 22, 2016, 05:38:02 AM
Fuel starvation?
What do the plugs say when you hit the "stop"?
Semicollapsed pump diaphragm can cause this type of behaviour.
Does it accept full throttle up to 5k?
Greenmonster - It wouldn't take full throttle at all. Checked pump actuation (no adjuster screw on the duals), and it appears to be squirting just fine, but of course no way to know how much. Will be road testing it this afternoon.
I'm pretty sure Greenmonster was talking about the fuel pump.
The FCR's will work just fine without the accelerator pump, I've tried unhooking it on my M750's 39s.
As long as you don't snap the throttle open like a crazy person, there's no difference.
IME, most diabolical jobs start innocently.
OK - As per original posts, the pump is new, tank cleaned and pump supplying & returning to tank. I've not checked what the supply rate is, but did try running it off just gravity, and it didn't help. So, I don't think the pump is suspect. I hear you about most 'diabolical' jobs starting innocently, and of course that can often be caused by someone looking for something the bike really doesn't have. I raced BSA singles (B50) for a number of years, and unless everything was optimized, they just didn't run great. That being said, due to persistence (and wanting to beat Honda's!!) we ended up with a pretty reliable 42/3RWHP bike, which is almost double what the factory ever got ;) With this bike, it's owner and his Dad were doing a few track days, and fancied they could squeeze a few more 'gee gee's' from the engine. If the plan had been a little better executed, from the outset, we perhaps wouldn't be in this situation? Suffice saying though, we feel a good part of the problems have been created from 'others' misinformed actions, trying to unsuccessfully put sticking plasters on a wound that wasn't healing without some major surgery!!
Best Laid Plans? Just modified the airbox lid, and road tested it -- not good >:(
(http://i67.tinypic.com/25iy840.jpg)
So - I clearly found a fault yesterday, and that's put to bed -- but???? One thing I'm noticing now (minus box lid) is a sort of squeaky noise when the throttle is blipped? Not sure it means anything, but it's something I never heard before. So - what next? [drink]
I marked the throttle, and it is right at 1/4 opening it does its biz. Try to roll through it, and it just bucks & coughs, but if you hold it over half throttle, it will sort of clean out a bit - and takes off like a scalded cat.
You raise the needles and run 165s with the open airbox? Its too lean otherwise.
Does it sound like little birds tweeting in the intake ? ;D if so its normal with FCRs. As long as its not pinging.
If the plugs get fouled the 60 slow jets are often the cause. Bike start easy?
Quote from: koko64 on June 22, 2016, 01:22:07 PM
You raise the needles and run 165s with the open airbox? Its too lean otherwise.
Does it sound like little birds tweeting in the intake ? ;D if so its normal with FCRs. As long as its not pinging.
Yeah - sounds a bit like a couple of hoarse canaries tweeting, no pinging though ;D. EMT Needles are in 5 right now, with 155's. I have few jets on hand, only a pair of 160's, and 185's and 65 pilots. Bike starts first turn, from cold --- if you can call high 90's air temps cold (with heat index at around 100) and idles nicely. Speeddog suggested EMS's in 3, but I don't have any [roll]
It will go better with 165s. 155s were intended for stock. Curious what your plugs say. I reckon too rich down low a d lean up top ime. If you think the bucking is midrange play with needles, but it could be an overlap from too rich a slow jet. Run 165 mains or risk damage. If riding slow and it starts fouling then change those slow jets to speeddogs baseljne. Throw in the 160s in the meantime.
Order some 50 and 52 slow jets and 165s from Powerbarn or Sudco. Usually the 60 slow jets are too rich on the 41s with some exceptions.
Only downside to these carbs is no choke. Accelerator pump squirts to prime and a smidge of throttle to start. In cold weather the pump squirts increase. The heat there at present is a factor but it should be harder to start without pump priming.
Fuel tap under the tank and mains easily accessed via bolt cap on float bowl as a race carb should. Very handy. Catch the fuel in a speay can lid.
OK Koko64, gotcha! Just put the 160 mains in it, but it's not even getting onto the main before its 'burp'. I'll order jets today, and see how that works. I roadraced for many years, and am very familiar with Mikuni VM Roundslide carbs (have stacks of jets/needles/parts) so I am totally used to jet changes. That was usually on bikes I built though, where I had a bit more of a say in how easy it was to get to the carbs [thumbsup] Just like the VM's though, these FCR's can feel like they are lean, when in actual fact they are fat, as it seems the 60 pilots are too much (on the road, not necessarily on the lift)
Keep in mind that the OEM fuel valve on that SS tank is no longer available, at least here in the US.
They've never struck me as being particularly robust.
Figure out a tool that will allow you to reliably and repeatably adjust the airscrew by only taking the air filter and lid off.
You may need to drill out the hole in the air horn a bit.
Oh, and you have my heartfelt condolences on your previous BSA affliction.
I've heard that it's nearly incurable, and no amount of therapy or self-medication seems to help.
You're a very lucky individual to have survived and gone on to lead a what appears to be a normal life.
Quote from: Speeddog on June 22, 2016, 03:00:45 PM
Keep in mind that the OEM fuel valve on that SS tank is no longer available, at least here in the US.
They've never struck me as being particularly robust.
Figure out a tool that will allow you to reliably and repeatably adjust the airscrew by only taking the air filter and lid off.
You may need to drill out the hole in the air horn a bit.
Oh, and you have my heartfelt condolences on your previous BSA affliction.
I've heard that it's nearly incurable, and no amount of therapy or self-medication seems to help.
You're a very lucky individual to have survived and gone on to lead a what appears to be a normal life.
Hey Speeddog, At least I made history with the B50, being the first person ever to put a single 'on the box' at Daytona in Sportsman 500 (in 04 I think) - with a 3rd. The disease is even worse than that though, as I also raced a Triton I built (Manx Norton rolling chassis, with pre-unit 650 Tri motor & Norton gearbox) to many successes (including 4 wins at Daytona) culminating in a National title in 04, in Classic 60's 650. We were getting an honest 52RWHP from that motor (honest meaning the Dyno belonged to Doug Chandler, and wasn't set up --- errr, optimistically!) Just to make matters worse, I raced an 88 Yamaha FZR1000 in the Isle Of Man Senior Newcomers Manx GP - in 88, finishing 17th from 46 starters. Still, I came home with a finishers medal!! I was sponsored by (amongst others) Works Performance Shocks, and got to race (REAL) Manx Nortons for owner Gilles Vaillancourt RIP.
So, I know all about the 'disease'!! I officially retired in 07, but still get a few laps in occasionally, at Harris Hill Raceway here in Texas - usually on a borrowed Kawasaki 300 (AAGGHH the Japs bikes!!)
I can easily get at the slow air screws (got the Sudco conversion) with just the air filter off.
(http://i64.tinypic.com/24deltz.jpg)
Pic is from Thunderhill in CA, on my Triton.
PS- Thanks to all for sound suggestions!
VMs and Amals. ;D
Quote from: koko64 on June 22, 2016, 04:46:38 PM
VMs and Amals. ;D
Hey now - I never mentioned Anals [laugh] Although their new Premier series are a whole lot better than the old ones, and I've sold/fitted quite a few. If you look at 'Customer Bikes' - West Coast Racing (Me!) on the British Cycle Supply website, you'll see a pair of Premier's I retro fitted to a Honda 305 (bike runs great with them!) I've had huge success with VM's, so no bad words - please ;)
PS - Jets ordered from Sudco for FCR's
I cut my teeth on Amals, but it seems VMs were the savior of Amal equipped bikes. They are even making new Monoblocks (I fitted some to a '66 Lightning awhile back). [thumbsup]
How's the 900CR going?
Hey Tony, Been out fishing for 4 days, and now back to the Salt Mines! Got jets from Sudco, and some richer needles (than the EMT's) A cursory look at the horizontal inlet valve (only one accessible without some major dismantling!!) shows opener at a fat 0.005", and closer about 0.03", so I just got a shim kit, and will get the valves all sorted out in the next couple of days. Checked the cam belts, and timing/belt tension good. I need to get all the 'physical attributes' perfect before going any further on this rascal ;) It's been getting in the way of regular service work, so I'm a bit caught up with that (once I get carbs back on/synced on a VF750R I have in!) and the 'Ducklet' will be back on the lift Monday.
Bloody V4 carbs. [laugh]
I go the extra mile with bench syncing them, as the hot syncing is a nightmare I have had --- more than I care to talk of >:(
the FCR's on the Duck were nigh on perfect on the Morgan Carbtune Pro - straight from Ultrasonic cleaning, and bench sync. I truly need to get this 'problem' put to bed, and will definitely be deep into the tyke come Monday. More progress reports soon!
I raced three VFR400/NC30's over the years in Formula 400. My fat hands struggled with their nooks and crannies. [laugh] Got a few 750s that come in, a smidge better (less worse). ;D
If you check my WCR FB page, you'll see an NC30 engine in for valve adjustment -- JUST the engine, on the bench, and so easy to work on!! Cute bikes - I like them [thumbsup]
SMALL UPDATE
Got into the valves yesterday - and found quite a bit that needed addressing. Remember, this engine has done so little since it had the big bore kit installed, I wasn't really expecting to find anything much to do. Both Exhaust openers had non-measurable gaps (less than 0.0015" - but shims still turning) and the vertical Ex closer shim was about 0.004" out of whack. Bless the top of that valve being a little mushroomed, which took forever to get to where I could get the shim off! So, all done, and am going to try some EMR needles on this excursion into the carbs. More to follow [popcorn]
PS - Tony? Going to the 165 mains you suggested, and - with the 50 pilots, what do you suggest as a starting position for the mixture screws?
In theory if the slow jet is correct then between 1-2 turns out is the theoretical range. I have had to run the IMScrews at about 1/2 a turn with our pooey fuel down here. Curious how many turns causes the motor to stall or falter as the slow jets should be good if you can get the motor to falter when going less than half a turn and more than two.
Didn't get it buttoned up until late, so just got time to fire it up briefly. I set the idle screws at 3/4, and noticed it is is a bit lean off the bottom (where it wasn't before!!) so, I'll put the sync on tomorrow, and see where they feel happy. Then - it's 'show time' for a quick road test, with the different jetting - with fingers firmly crossed. The customer thinks the bike has made a little bed for itself in the corner of the shop -- I have had it that long!! ;D
1 to 1 1/2 turns could be good according to the theory. Should be a little cold blooded with non existent choke which means it's close. The 60 slow jets in 41s start too well if you know what I mean.
Does it feel like you are hitting a rev limiter?
I have seen aftermarket ignition boxes cut power as a rev limiter way too early. They ran great until the same rpm and then killed it. In our case we popped on some oem boxes and all was good again. Know that some of the Ducati performance boxes also had built in limiters.
I have also seen kits to run non-resistor plugs and wires that caused all kinds of issues as the noise messed with the ignition.
Best thing you could do would be to get the bike to a Dyno and pull air fuel. I had a customer trying to jet a bike that had bad boxes so until you see what air fuel and what happens when it falls on its face you might be spinning your wheels.
Clubhouse, If you read the whole thread, you'll get a better feel for what's going on, but - yes, it's just like it's hitting a rev limiter. After all that's been done, it's really getting sillier than better though! Unfortunately, we don't have a Dyno facility anywhere close by, and even if we did - it's such a bear getting to the carbs to make adjustments, that we'd need a big fist full of smackeroos to make it all work!! Takes me about 1 1/2hrs to R&R the carbs, to make jet changes [roll] (stock airbox base & all coils/igniter modules mounted to it)
Tony - you looking in? 50 pilots, with mixture screws at 1-1/2 turns, and it sounds happy off the bottom. EMR needles in 4, with 165 mains - AND, our 'gremilns' are still having a field day - YET, it seemed on the quick road test I did, the problem may have shifted a bit - to a little more than 1/4 throttle. However, we aren't supping champagne today :'(
Carbs do not usually act like a limiter, the point I was trying to make is you may be heading in the wrong direction with the carbs (electrical not fuel) . If the carbs were off as little it would not run great but not shut off like a limiter. Too lean a main and it should feel flat, too rich a bit choppy but if you are within 10 jet size it should be good but not great.
Were the heads ported? If so then go leaner on the mains.
What RPM does it happen at and is it consistant regardless of throttle position? can to hold 1/2 throttle to the same RPM and re-create the problem? 1/4 throttle etc.
The bike with the bad aftermarket boxes worked just as you describe but without a dyno it is hard to see what is happening.
What order are the pick up wires in where they enter the ignition boxes ?
What color wire enters the box as you have the connectors at the top and facing you
Two pin Three pin Box #2 Two pin Three pin
Black yellow Black Brown/green red White Red Black Gray Red
What do you have?
FCRs are pretty good at taking an over rich main jet when asking for it so it could still be an ignition pick up or ignitor issue Eric suggested. The 185 mains I understand killing the motor but a jet or two must be something else. With an unported motor and open but stock airbox I would have even tried the stock needles first. Sudden killing of power might still be electrickery.
Quote from: clubhousemotorsports on July 05, 2016, 04:40:54 PM
Carbs do not usually act like a limiter, the point I was trying to make is you may be heading in the wrong direction with the carbs (electrical not fuel) . If the carbs were off as little it would not run great but not shut off like a limiter. Too lean a main and it should feel flat, too rich a bit choppy but if you are within 10 jet size it should be good but not great.
Were the heads ported? If so then go leaner on the mains.
What RPM does it happen at and is it consistant regardless of throttle position? can to hold 1/2 throttle to the same RPM and re-create the problem? 1/4 throttle etc.
The bike with the bad aftermarket boxes worked just as you describe but without a dyno it is hard to see what is happening.
What order are the pick up wires in where they enter the ignition boxes ?
What color wire enters the box as you have the connectors at the top and facing you
Two pin Three pin Box #2 Two pin Three pin
Black yellow Black Brown/green red White Red Black Gray Red
What do you have?
Looking from back of bike - LHS 2 pin White/Red, 3 pin Black/Green & Brown/Red RHS 2 pin Black/Yellow, 3 pin Black/Grey/Red
Quote from: koko64 on July 05, 2016, 05:00:48 PM
FCRs are pretty good at taking an over rich main jet when asking for it so it could still be an ignition pick up or ignitor issue Eric suggested. The 185 mains I understand killing the motor but a jet or two must be something else. With an unported motor and open but stock airbox I would have even tried the stock needles first. Sudden killing of power might still be electrickery.
Hey Tony - Who knows if the heads have been fiddled with? It really feels like it is starving for fuel, when the needles come into play, so I ordered some really rich ones - GJM's, and some basically between them and the EMR's I have in it - FHN's. At least I can get a better feel for what it's asking for, by having a better selection of needles. Sure, a dyno would be great - but, at $100 an hour, I'd be a poor man just doing 3 or 4 jet changes -- plus, I'd maybe need more jets/needles than I have!
I never saw Eric suggest that you jet it on a dyno. He suggested to do
a dyno run with an EGA to see if the air/fuel ratio is close when this thing acts like, in your words, it hit a rev limiter.
...and when he say's...
Quote from: clubhousemotorsports on July 05, 2016, 12:40:27 PM
Does it feel like you are hitting a rev limiter?
I have seen aftermarket ignition boxes cut power as a rev limiter way too early. They ran great until the same rpm and then killed it. In our case we popped on some oem boxes and all was good again. Know that some of the Ducati performance boxes also had built in limiters.
I have also seen kits to run non-resistor plugs and wires that caused all kinds of issues as the noise messed with the ignition.
Best thing you could do would be to get the bike to a Dyno and pull air fuel. I had a customer trying to jet a bike that had bad boxes so until you see what air fuel and what happens when it falls on its face you might be spinning your wheels.
It's because he's seen it.
Quote from: ducpainter on July 05, 2016, 05:44:42 PM
I never saw Eric suggest that you jet it on a dyno. He suggested to do a dyno run with an EGA to see if the air/fuel ratio is close when this thing acts like, in your words, it hit a rev limiter.
...and when he say's...
It's because he's seen it.
Ducpainter - Yes, I understand what Eric is saying - but, as I replied, we don't have an accessible dyno locally -- period, so that's ruled out. I did more than my fair share of dyno runs when I was building/racing bikes, and fully understand the huge benefits of having a smooth fuel curve. In this case, it is unfortunately the 'seat of the pants' dyno, and I am sincerely thankful for all the help so far.
Eric - thanks for the sensible suggestions, I really do appreciate the help here. The wiring I have does seem to be reversed from what you wrote?
Quote from: Brid on July 05, 2016, 05:58:25 PM
Ducpainter - Yes, I understand what Eric is saying - but, as I replied, we don't have an accessible dyno locally -- period, so that's ruled out. I did more than my fair share of dyno runs when I was building/racing bikes, and fully understand the huge benefits of having a smooth fuel curve. In this case, it is unfortunately the 'seat of the pants' dyno, and I am sincerely thankful for all the help so far.
I think you're missing the point.
I have to admit that I know Eric, and without a dyno or EGA to prove it, my gut feeling is he's telling you to stop chasing jetting, and look at ignition, if in fact this bike acts like it's hitting a limiter.
I certainly know I'd trust him, and his many years of Ducati experience...don't want to date him but I met him in '00 and he had been at the shop a while...more than an ebay vendor that assures you his ignition boxes are the ticket.
Now if the bike is just a little flat at a certain throttle position/rpm, then jet away.
Which is it?
Quote from: ducpainter on July 05, 2016, 06:19:50 PM
I think you're missing the point.
I have to admit that I know Eric, and without a dyno or EGA to prove it, my gut feeling is he's telling you to stop chasing jetting, and look at ignition, if in fact this bike acts like it's hitting a limiter.
I certainly know I'd trust him, and his many years of Ducati experience...don't want to date him but I met him in '00 and he had been at the shop a while...more than an ebay vendor that assures you his ignition boxes are the ticket.
Now if the bike is just a little flat at a certain throttle position/rpm, then jet away.
Which is it?
Going back to when this thread started - yes, it feels like it's hitting a limiter, and that's why I changed out boxes/coils/wires (the spark was weak), went back & double checked the air gap/timing, checked cam belt timing, and just did a valve adjustment. It was doing this with the OLD Kokusan boxes/coils/wires, and first advice given, was that the FCR's must be correct in all stages, or they will give this condition. Everything mechanical is now addressed, so it's either 'lecktrickery' or jetting. There have been a couple of times when (on the road) I just twisted on, and tried to get it through 'the bog' - which is consistently at 1/4 throttle, and when it starts to clear, it wants to take off big style. the bike doesn't have current license tags, so I can't go too far from the shop, and my 'test run' street isn't too long! Would bad boxes clear up at higher revs?
If the pick ups are retarded and the ignitor boxes have a retarded map for hi comp then that could cause it. I dont know not hearing/feeling the motor. Non R plugs can cause issues for sure as Eric stated.
Quote from: koko64 on July 05, 2016, 09:07:08 PM
If the pick ups are retarded and the ignitor boxes have a retarded map for hi comp then that could cause it. I dont know not hearing/feeling the motor. Non R plugs can cause issues for sure as Eric stated.
I retarded the timing a couple of degrees, as per everyone's suggestions, and it did this with both the stock boxes, and the new ones. As previously mentioned, using DPR8EIX-9 plugs. Odd that both boxes did the same thing? At this stage I'll believe anything that will cure the problem [roll]
Plugs are fine then. Stock boxes have stock timing but maybe fancy ignitors knock off a few more degrees, so I dont know. Pick ups run at about 1mm =0.7 deg when slid back. Who knows if they were already retarded when you got the bike with the hi comps and how much? Maybe Eric remembers where the stock location is in relation to the lines on the case. I had it written somewhere...
Quote from: koko64 on July 05, 2016, 09:36:20 PM
Plugs are fine then. Stock boxes have stock timing but maybe fancy ignitors knock off a few more degrees, so I dont know. Pick ups run at about 1mm =0.7 deg when slid back. Who knows if they were already retarded when you got the bike with the hi comps and how much? [bang]
Not got degree marks on flywheel, so just took an educated guess from stock position. With the strobe, it's clearly a little retarded - both at idle, and full advance. isn't that what everyone advises for high comp/modern (crap) fuel? In Tx we are also having to deal with Ethanol (up to 15%) in it. Ethanol has water in it- so, maybe we'll soon be tuning steam engines!! ;D
There are lines on the case inner that you can measure the pick up brackets against. All good fun. ;D
Its hard when you dont know where you started from and a few cooks have been in the kitchen.
Quote from: koko64 on July 05, 2016, 09:50:54 PM
There are lines on the case inner that you can measure the pick up brackets against. All good fun. ;D
Its hard when you dont know where you started from and a few cooks have been in the kitchen.
When first strobed, it was too far advanced - which is what prompted the first side case removal. Had it on & off about 4 times now, and finally put a bought gasket on there, so any further removal should be pretty simple ;) Surely the strobe saying it's correct at idle advance - and again at full, is good enough? I've watched it a good few times now, and when it jumps to full advance, it stays steady there as revs rise. So - having a radical retard built in doesn't appear to be the issue. Why would it be different under load (on the street?)
I guess 2 to 4 deg works but what if its 6 -8 degrees retarded through the range.? Its all I can think of. Going even richer on needle type than EMR/EMS sounds way too rich.
Is it breaking down then muddling through or just smack hitting a wall?
I cant tell without riding it.
I took a look at my monster and it matches your wiring so you should be good there.
Base timing for the 900 is set static in the middle position of the timing plate. If you look at the bottom of the plate you will see 4 or 5 little points that should line up with a web on the case. Stock timing is in the center position, Hi comp. pistons usually get set with the timing plate rotated counter clockwise (as you face the plate) to the maximum position. If you do not do this it should not give you the effect of what you are feeling.
Ignition boxes with the wrong map will react to rpm ( like a rev limiter set too low)not throttle position so when you are having the problem at 1/4 throttle where is the rpm's? If you have a set of the bad aftermarket boxes you may only be able to rev to say 7000 rpm max. No boxes will give you a stumble usually , a bad box will simply be dead if oem.
Note that some projected plugs will hit hi-comp pistons, if it has cleared so far you might be fine but some pistons will touch a projected plug enough to close the gap.
QuoteI just twisted on, and tried to get it through 'the bog' - which is consistently at 1/4 throttle, and when it starts to clear, it wants to take off big style.
Is it the bog at 1/4 throttle you are calling like a rev limiter?
If so then I would not think electrical but carbs.
Back to my earlier questions
1. is it RPM related or throttle position?
2. If RPM ,
what RPM ?
is it at the same rpm every time?
3.Have you dissected the throttle to determine the position?
4. is it consistently at the same throttle position
5. multiple positions?
6. will it pull to 8000rpm in any throttle position?
7. does it pull better if you very slowly open the throttle vs a quick twist wide open?
Hi Eric - as I mentioned, I only have a short street to test the bike on, and there's traffic everywhere. Yes, I have the throttle 'dissected' and it is always at 1/4 throttle. I haven't paid attention to what revs it's doing right there, and need to do so. If you 'short shift' before it breaks up, it is fine. A couple of times, I have tried to rev through it, but not paid any heed to what revs it is doing. I'll do a bit more thorough test this afternoon, checking revs etc
1/4 throttle should not be electrical or main jets.
You still need to do the other tests
you may need to take it somewhere to open it up we do need to know if it cleans up past 1/4.
At some point you need to take off the handcuffs.
You're spinning your wheels, and costing either the company, or the customer, more money than it should.
Give me some specs on the bike and I can check my jetting log to see if I have anything in the ballpark.
944
exhaust? oem header or 2-1 or spaghetti?
41mm bank fcr
what velocity stack red,blue or aluminum
open or closed airbox
porting or stock (ported will have the inlet touched where a stock head will have hand work only near the bowl).
dual or single plug heads?
oem cams (OHT and VHT on cam ends)
Each bike is different so you will see differences this is why a "kit" may not work for all applications and why I have to re-jet often on the dyno. Yes I do change needles and on some bikes it is often but a 944 is not normally one that needs different needles. Note also the Monsters were /are always richer jetting than supersports on main jets so a 185 sounds way rich for me but I will take a peek.
Quote from: ducpainter on July 06, 2016, 10:38:29 AM
At some point you need to take off the handcuffs.
You're spinning your wheels, and costing either the company, or the customer, more money than it should.
The company is mine, and I am not charging the customer anything like full hourly rates for doing this. I have now taken this as a personal vendetta, and won't quit until we get to the bottom of it. I sincerely wish it were spinning the wheel!! So, I'm pretty sure I've covered most of the obvious things that I did find problems with. Weak spark, incorrect pick up coil air gap/ignition timing, incorrect valve clearances. When I got the bike in, it had sat for around 12 months - the carbs were in a mess, and were duly ultrasonically cleaned. Once the 'glitch' reared its head, I started checking more components, finding the coils were at the high end of specs, so changed them out for Nology (many suggestions to do that) Changing the igniter boxes seemed to be the sensible thing to do, as was fitting Taylor Spiro Pro wires, and Irridium plugs. As per instruction, I cut the airbox top off. So, I do agree a Dyno base run would tell me a lot, but I don't have that facility available locally.
As you consider I'm spinning my wheels, what would you suggest as next course of action? (Not knowing if someone maybe did some porting on the heads)
Quote from: clubhousemotorsports on July 06, 2016, 10:45:26 AM
Give me some specs on the bike and I can check my jetting log to see if I have anything in the ballpark.
944
exhaust? oem header or 2-1 or spaghetti?
41mm bank fcr
what velocity stack red,blue or aluminum
open or closed airbox
porting or stock (ported will have the inlet touched where a stock head will have hand work only near the bowl).
dual or single plug heads?
oem cams (OHT and VHT on cam ends)
Each bike is different so you will see differences this is why a "kit" may not work for all applications and why I have to re-jet often on the dyno. Yes I do change needles and on some bikes it is often but a 944 is not normally one that needs different needles. Note also the Monsters were /are always richer jetting than supersports on main jets so a 185 sounds way rich for me but I will take a peek.
Eric - Ferracci 944 kit
Dual FCR 41's
Adapter velocity stacks, for stock airbox
Airbox lid cut off, using stock air filter
Stock headers, with V&H SS2R carbon slip ons
Single plug heads
No idea about porting as I've not had the manifolds off, and haven't removed cam end caps, so not sure what cams.
As of now -
165 mains
EMR needles in 4
200 main air jet
Slow air = 1 1/2 turns
50 pilots
Mixture screws = 1 1/2 turns
Feels OK off the bottom, and returns to idle OK
Procom PE-C-MD900-A igniter boxes
Nology Pro Fire PFC-30-S-3.0 coils
Pick up coils within ohmage specs, and air gap set as per book
Quote from: Brid on July 06, 2016, 12:04:07 PM
The company is mine, and I am not charging the customer anything like full hourly rates for doing this. I have now taken this as a personal vendetta, and won't quit until we get to the bottom of it. I sincerely wish it were spinning the wheel!! So, I'm pretty sure I've covered most of the obvious things that I did find problems with. Weak spark, incorrect pick up coil air gap/ignition timing, incorrect valve clearances. When I got the bike in, it had sat for around 12 months - the carbs were in a mess, and were duly ultrasonically cleaned. Once the 'glitch' reared its head, I started checking more components, finding the coils were at the high end of specs, so changed them out for Nology (many suggestions to do that) Changing the igniter boxes seemed to be the sensible thing to do, as was fitting Taylor Spiro Pro wires, and Irridium plugs. As per instruction, I cut the airbox top off. So, I do agree a Dyno base run would tell me a lot, but I don't have that facility available locally.
As you consider I'm spinning my wheels, what would you suggest as next course of action? (Not knowing if someone maybe did some porting on the heads)
I'd have the owner register it so you can do a proper road test and diagnosis of the symptoms. It's pretty tough to figure out what needs to be done when all you have is a short street with lots of traffic.
At some point it will have to be done without a dyno being an option
The guys here, both Tony, Eric, howie, and Speeddog (Nick) are all vastly experienced, but you can't help them help you right now because you can't actually ride the bike and answer their questions.
Quote from: ducpainter on July 06, 2016, 12:41:19 PM
I'd have the owner register it so you can do a proper road test and diagnosis of the symptoms. It's pretty tough to figure out what needs to be done when all you have is a short street with lots of traffic.
At some point it will have to be done without a dyno being an option
The guys here, both Tony, Eric, howie, and Speeddog (Nick) are all vastly experienced, but you can't help them help you right now because you can't actually ride the bike and answer their questions.
Only nonsense there is, we'll have to trailer the bike to the closest State Inspection station, as you have to get the inspection to re-register it. Yes - I understand I cannot give every fact, but I really do appreciate those here trying to help, and know we'll get to the bottom of it ;D
Quote from: Brid on July 06, 2016, 12:54:32 PM
Only nonsense there is, we'll have to trailer the bike to the closest State Inspection station, as you have to get the inspection to re-register it. Yes - I understand I cannot give every fact, but I really do appreciate those here trying to help, and know we'll get to the bottom of it ;D
Still needs to be done, and even if you get this glitch out, you won't be able to get the entire jetting sorted without the thing being 'on the road'.
Okay I have few similar setups as we prefer the 39's over the 41's so most of my jetting was for the smaller carbs. I did have a couple though running the 41's so you can see where we ended up. They would have been checked on either mine or the dealership dyno. Full spec as well as some info is missing so just use it for a guideline as different bikes will have different needs.
I assume your FCR's are a bank as you are using the stock airbox so I will take it as a given.
#1
155m
62 pilots
#3 needle ELV
Fuel screw 1/2
Air screw 1-1/2
#2 open air box (like yours)
full termi exhaust
150 main
#4 needle (elv) changed to a EMR run in #7 so you can see some big differences
65 pilot changed to 62
Fuel screw 1/2
air screw 1-1/2
#3 985
dual plug heads
porting
split 41's
Full DP exhaust
155 main
62 pilot
1/2 fuel screw
2-1/2 air screw
#5 needle ELV
Monsters with 39's 160 and larger mains but a SS should be smaller. I would start by swapping in some 155's and try a 62 or 65 pilot. I would start with the ELV needle in the middle (3 or 4) and base line the fuel screw and air screw as above.
Nate is right in that you will need to test it sometime/somewhere and if the customer is ever going to ride it I assume he will need that inspection anyway. in a pinch see if there is a private road, track,airport that can accommodate you. I used to take mine to the local race track and drive their back parking lot.
Quote from: clubhousemotorsports on July 06, 2016, 02:01:18 PM
Okay I have few similar setups as we prefer the 39's over the 41's so most of my jetting was for the smaller carbs. I did have a couple though running the 41's so you can see where we ended up. They would have been checked on either mine or the dealership dyno. Full spec as well as some info is missing so just use it for a guideline as different bikes will have different needs.
I assume your FCR's are a bank as you are using the stock airbox so I will take it as a given.
#1
155m
62 pilots
#3 needle ELV
Fuel screw 1/2
Air screw 1-1/2
#2 open air box (like yours)
full termi exhaust
150 main
#4 needle (elv) changed to a EMR run in #7 so you can see some big differences
65 pilot changed to 62
Fuel screw 1/2
air screw 1-1/2
#3 985
dual plug heads
porting
split 41's
Full DP exhaust
155 main
62 pilot
1/2 fuel screw
2-1/2 air screw
#5 needle ELV
Monsters with 39's 160 and larger mains but a SS should be smaller. I would start by swapping in some 155's and try a 62 or 65 pilot. I would start with the ELV needle in the middle (3 or 4) and base line the fuel screw and air screw as above.
Nate is right in that you will need to test it sometime/somewhere and if the customer is ever going to ride it I assume he will need that inspection anyway. in a pinch see if there is a private road, track,airport that can accommodate you. I used to take mine to the local race track and drive their back parking lot.
Eric - thanks for digging this out. When I got the bike in, it had ELV's in 4, 65 pilots, 185 mains, 200 main airs, slow air at 1 1/2 turns, and fuel screws at 3 - and was doing pretty much exactly what it is doing right now. I have tried EMT and now EMR's, in different clip positions, but it hasn't made a difference. Chris Kelly from Ca Cycleworks maintained it was far too lean with ELV's, and to go to EMT's, so - I have had info both ways!!
You have 2 guys suggesting settings that are close. While every bike is different and will need some tweaking if you're within a jet size or a clip position the thing should be rideable.
I'd put the Kokusan boxes back in to see what happened.
+1. I would to double check. Aftermarket ignitors and retarding the pick ups could have doubled up on ignition adjustments.
Some people like LT Snyder have pointed the finger at Nology coils too.
Most bikes have run the ELV if supersports and EMT if monsters. Little difference between 39 and 41 jetting.
For this bike to be off that bad it needs something else to be different from the norm. When I convert 800's to carby and port and cam with race pistons we need to step away from the norm. What you have should not be different unless you also have cams and or porting, you should check. If you are no different from the norm then I think you may be chasing the wrong thing but chasing blind. Do you have access to an gas tester? CO and HC would do.
Somehow you need to figure out if you have a fuel problem or something else, without a way to tell what you have for fueling it will be a lot of work and guessing.
If you are stock other than what you have desribed then I would consider going back to the oem coils,wires ignition boxes and some DR8e plugs. Make sure you have resistor caps as well (5k).
Before you get too far remember to test those RPM throttle positions, one test/change at a time.
Quote from: koko64 on July 06, 2016, 02:47:24 PM
+1. I would to double check. Aftermarket ignitors and retarding the pick ups could have doubled up on ignition adjustments.
Some people like LT Snyder have pointed the finger at Nology coils too.
Just tried the Kokusan boxes again, and still not good. It is always at 1/4 throttle, and around 5 1/2 to 6K rpm. Will be getting it licensed soon, so will get some (legal!!) miles on it, and see where we are. Again, just trying to get through the 'garbled' glitch, with a slow throttle opening, it feels like it really wants to clear out and go.
I was thinking you should borrow a known good set of OEM igniters just to rule them out. Since you did that I have to agree with Nate. You are quite knowledgeable, your limit seems to be the inability to go for a proper road test.
Quote from: howie on July 06, 2016, 03:55:30 PM
I was thinking you should borrow a known good set of OEM igniters just to rule them out. Since you did that I have to agree with Nate. You are quite knowledgeable, your limit seems to be the inability to go for a proper road test.
Howie - I'd really like to take the bike to the racetrack, get it ironed out - and get some laps on it!! I will have a pair of known good igniter boxes next week, plus - another brand new (in box) set of FCR41's ( I am very intrigued to see what jetting/needles they have in them, as they were bought at the same time as the ones on the bike). The owner and his father used to do track days on 900's & 916's, and have a couple of running 900SS's we will borrow the boxes off. Pain is, they are a couple of hundred miles from my shop, so I won't have them until Monday :(
MO UPDATES
As I'm waiting on alternative jetting, I decided I'd run it with the EMR's as fat as they'd go -- in #7 (Just for the halibut ;D). Got it all back together, fired it up - and the charge light stayed on. A quick check of the stator output shows nothing between the three 'legs', and with an ohm meter, again - nothing between the legs, but nothing going to ground.
Question - Even with a good fresh battery (12.5 v) would the charging system going out make any difference in the running?
Depends how low the battery goes when it's running.
Dunno about on the carbie SS, but the IE fuel pumps are ~15 amps or so when running, IIRC.
So, system voltage could be sagging quite a bit.
And thus perhaps the coils aren't charging fully....
Quote from: Speeddog on July 07, 2016, 02:51:47 PM
Depends how low the battery goes when it's running.
Dunno about on the carbie SS, but the IE fuel pumps are ~15 amps or so when running, IIRC.
So, system voltage could be sagging quite a bit.
And thus perhaps the coils aren't charging fully....
Thanks! I found the stator wires in rough shape - hidden inside the sheathing, and patched them up. Now I have around 50v ac per leg at revs (about 16 at idle) but it's still not putting much into the battery. Gets up to about 13v, then drops back to mid 12's at revs, so -- another rectifier is needed
16 VAC at idle and 50 at some revs, that's fine.
If the bike continues to start/restart under its own power it is doubtful the charging system has anything to do with your running problem. The bike will break up when voltage gets low but with a carby that's pretty low and it does not get better or re-start after that.
Carby charging systems are pretty weak but sufficient most of the time. Have you had to keep charging /jump start the battery to get it started?
Quote from: clubhousemotorsports on July 08, 2016, 05:09:12 AM
If the bike continues to start/restart under its own power it is doubtful the charging system has anything to do with your running problem. The bike will break up when voltage gets low but with a carby that's pretty low and it does not get better or re-start after that.
Carby charging systems are pretty weak but sufficient most of the time. Have you had to keep charging /jump start the battery to get it started?
No - no jump starts. When it came in, it had a duff battery, that was showing 12+ static, but sinking down to 4 or 5 when you hit the starter. New sealed one on it, and it's not done much work yet. This one will take a quick dive to around 10+ when you hit start, but picks up again immediately
So I would not spend the time on the charging system as it looks like it is working and you have bigger fish to fry.
Quote from: clubhousemotorsports on July 09, 2016, 08:28:59 AM
So I would not spend the time on the charging system as it looks like it is working and you have bigger fish to fry.
The charge light is still on, and I am not going to run it with anything like a chance of the battery taking more of a beating than it necessarily has to. We will get a new rec/reg, and proceed!
1998 IGNITER BOX WIRING?
Try as I may, I cannot find a 98 diagram for this bike, and have been muddling my way through with a 96 diagram. Just got a Factory manual 'donated' but unfortunately it is a 91 book :(
I know we've had a bit of a chat about the igniter box wiring, but it seems every book I have is different to what I have on the bike. Does anyone have a 98 900SS that they can verify the colour coding?
Here's what I have - looking from back of bike
RH Coil = Vertical cylinder - Grey/ Red on coil
RH Ign Box - Reading from L to R, 2 pin plug = Black/Yellow. 3 pin = Black/Grey/Red
LH Coil = Horizontal cylinder - Green&Brown/Red on coil
LH Ign Box - Reading from L to R, 2 pin plug = White/Red. 3 pin = Black/Green&Brown/Red
Seems both books I have show the LH 3 pin having the Black/Red 'flip flopped', but both books with Green&Brown in the middle. Someone could be playing tricks with this - so, can anyone please confirm? I know the Black is a ground, so - what would happen if these wires are in fact reversed?
Nobody have any 1998SS pics?
Sorry man I don't. I'm a bit lost on your problems since I'm not there helping you over a beer. I know of people that have swapped the wires without ill effect bar bad running but I can't guarantee it won't blow the boxes.
Quote from: koko64 on July 13, 2016, 06:17:06 PM
Sorry man I don't. I'm a bit lost on your problems since I'm not there helping you over a beer. I know of people that have swapped the wires without ill effect bar bad running but I can't guarantee it won't blow the boxes.
Tony - that's not what I was wanting to hear -although the "Helping you over a beer" sounds like a winner [drink] [drink] None of the diagrams I've seen show any colours on the pick up wires to their plugs, however -the 96 Haynes book I have does at least mention colours, at least for which cylinder is which, - but not the wires in plug orientation. Both books I have show the power wire to the boxes/coils as Brown, and this one is Red. OK - that's not too difficult to figure out. It depends on which direction you look at the 3 pin plug wiring in the books, as they don't have any 3d orientation. A picture of one (even if the power wire is Brown!!) actually on a running bike would put my mind at ease! Whilst waiting for the new Rec/Reg arriving (tomorrow) I have been (again!) checking all the ignition wiring, and came up with yet another anomaly? Where all the coil/box wiring 'necks' down, into the 2 wire plug (on RHS of airbox) it makes sense that one is a power wire (from Stop/run switch) and the other a ground. So - why, with the Ignition switch OFF, and Stop/run switch on Run, do both the pins on the switch side of the plug read continuity to ground? With the Ign switch on, the power wire reads about 11.5 VDC - when battery is over 12VDC. Seems I often fight 'lecktrickery' gremlins - especially on older Jap bikes, but the Italians are generally a bit easier to sort out :o
I've asked a mate with a 750 and stock boxes to send me some pics. The 900 I'm working on is Ignitech equipped and all apart.
Quote from: koko64 on July 13, 2016, 08:26:01 PM
I've asked a mate with a 750 and stock boxes to send me some pics. The 900 I'm working on is Ignitech equipped and all apart.
Thanks mate - next round is on me [wine]
(http://i1024.photobucket.com/albums/y304/tonykokonis/IMG_3140_zpsqjbc7jl0.jpg)
(http://i1024.photobucket.com/albums/y304/tonykokonis/IMG_1168_zpsgcywqdas.jpg)
A buddy up the road sent me these. It's all I got.
That's good Tony - looks like both the Blacks are on the LHS of the plugs, so that answers that -- I'm good there. Got the new Rec/reg installed, but still no difference. Just so happens, the owner came up with another pair of stock igniter boxes (off a running bike) AND, another pair of the very same FCR's - brand new in the box (They ordered 2 sets at the same time, and these (on bike) were the only set used) So - I'm just putting the new ones on -- more news later!
THE GREMLINS STRIKE AGAIN
Well - you'd think you couldn't go too far wrong -- installing a brand new set of carbs - out of an unopened package. They were bought at the same time as the ones that were on the bike, around 2 years ago. I jetted the new ones as per one of Erics Dyno runs --155 mains, 60 pilots, mixture screws at 1/2, and slow air at 1 1/2, with ELV's in 4. I synced them, and set the float levels (were at 10mm - not the 9mm specced) I even put a breather line on them! Sat back and smoked a fag, thinking - yup, a nice set up --- THEN, i turned the petrol on ----- AND, it started pis*ing out of the fuel rail. I disconnected the pump - and it of course slowed down, so I had a stab at firing it up. First off, it didn't want to fire - but finally did, and would not take any throttle at all. Even after a bit of coaxing, it is clearly WAY lean on the pilot circuits, and if I let it return back there - it did NOT want to rev at all. So - I shut it down - wondering if someone forgot to put the bloody O-rings on the rail?????
Now we have another completely different set of circumstances, and I've got to pull it all down -- again, and pull the rack apart - to put O-rings in it [bang] However - where I had a bike which fired first turn before - now I have one that has to spin up a bit -- so at least - it's a different day, and a different problem -- Sheesh [roll]
THAR SHE BLOWS!!!
See this thing - sitting looking all pretty & innocent on the lift - like nothing ever happened! I pulled the fuel rail and replaced the o-rings, which didn't look bad -- put it all back together -- AND --- it still leaked. Closer inspection found a hairline crack in the plastic T, and - these are new carbs - straight out of the box. So - I had to 'borrow' the rail from the original (the cursed set!) carbs. A couple of hours later, and I'm off like a herd of turtles for a quick test spin -- and YAAAAAHOOOO!! It runs like a train!! I went to a 65 pilot, and at 1 1/2 turns on the mixture screws, it is pretty happy It's off to get inspected tomorrow, then we can do a full 'shake down', and re-jet if needed, but for now - it's running well! Kudos to all here that threw out suggestions, and helpful ideas. I have no idea what is going on with the original FCR's - and I may just have to take them to the bandsaw and cut them apart completely -- hateful Li'l Bastids :o
(http://i68.tinypic.com/2jbk3ky.jpg)
[clap]
Don't cut up those demonic carbs, just give 'em to me.
I'll even pay shipping.
I'll pay shipping to Australia, and hire a Priest. ;D
Quote from: koko64 on July 16, 2016, 03:23:29 PM
[clap]
Do I hear a cheer from the balcony? Thanks Tony - I'm chuffed we got to a bit of chatting [beer]
Cheers. [beer]
Yay!!! Glad all is finally working.
Unless there is something wrong with the castings those carbs can be fixed.
Quote from: howie on July 16, 2016, 03:59:58 PM
Yay!!! Glad all is finally working.
Unless there is something wrong with the castings those carbs can be fixed.
Howie - thanks for the nod! I've never had such a frustrating problem, and this is NOT my first rodeo ;D. But - along the way, I did discover a lot more stuff that needed addressing, and of course - the bike is so much happier now. If I had any C4 -- there would be a big bang outside the shop tonight, and someone a half mile away would find some melted FCR's in their garden tomorrow. But - I'll discuss it with the owner, who may want to just stick them in the Ultrasonic cleaner for a week, buy a new fuel rail, and sell them! Thanks for the help :)
To all those interested in the carbs -----? The rest of the installation kit is in the box - again, unopened (bellmouths, adaptor & funnel kit) It's really up to the owner, but I'm pretty sure he doesn't have a job for them. What do you think would be a fair price? Not a mark on the carbs - just need a new fuel rail.
Only reason I'm asking is - I'm getting sunburned, stood on the side of the Freeway - just waiting for a Mack truck to come close enough for me to slip them under the wheel - and, it's already 45 minutes past beer o'clock [shot]
[clap] [thumbsup] [beer]
THE END?
The owner rode it away, and home (around 12 miles or so) on Sunday, and said it never missed a beat, revved freely - and had far more power than it ever had before! So - I guess we got it pretty close ;) He'll give it more of a run, once it has license tags, and let me know how the plugs are looking - and of anything else it needs. Looking Good Lucy [thumbsup]
[thumbsup]
Quote from: koko64 on July 20, 2016, 08:37:10 PM
[thumbsup]
Back at ya mate [thumbsup] [thumbsup] [beer] [beer]
I wonder if the bad carbs had crook floats or blocked jnternal passages.
Quote from: koko64 on July 20, 2016, 09:46:23 PM
I wonder if the bad carbs had crook floats or blocked jnternal passages.
The floats were good Tony, not crook at all. I'm beginning to wonder if there is a piece of production swarf floating around in one of them? I had a new VM Mikuni one time, that just wouldn't respond to any mixture screw adjustments, and sent it back under warranty -- it wouldn't idle under about 2 grand or so. Never did find out what was wrong with it - and never test rode the bike, so I don't know how it would have affected the overall performance. Those carbs were sh*tty when the bike came in, having sat for about a year with our pi*s poor petrol (with over 10% ethanol - which has bloody water in it!) but, after ultrasonic cleaning, looked grouse - and I was tickled they looked so good. I mean -- c'mon, they are a rather sexy looking after all. But -- it just shows you that you can't take anything for granted - and the li'l bastids led me on a long chase - whilst just quietly sitting there like little sex pots :o Of course, they are way out of any warranty period, so - all the moolah for getting it sussed was down to me just not giving up, and the customer understands the BS I went through. I stock a few Mikuni carbs, and - had it not been such a special 'set up' - would have definitely tried different carbs (had it been a side draft situation) At around $1K USD for the kit, it's not something I keep 'on the shelf', as I don't get too many Ducks in (mainly Jap/Italian/Brit) and it's so bloody fortunate that the customer had another complete NOS kit, or I may have gone worse bankrupt than I am [roll] What good comes out of it all --? Well - I've met (and pestered!) a good few folks here, that I'm very grateful to, for any help I got -- AND, it's another one in the 'book' of quare problems you encounter ----- when you can't plug a computer in and suss the thing out! There is a bit of a possibility the customer may take the bike to our local track - and we can give it a good thrashing, and get it fine tuned --- AND, I may even get some laps in [Dolph]