WAYWARD 1998 944SS - NEEDS HELP

[koko64]

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.

[Brid]

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 

[koko64]

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...

[Brid]

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?

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!! 

[koko64]

There are lines on the case inner that you can measure the pick up brackets against. All good fun.
Its hard when you dont know where you started from and a few cooks have been in the kitchen.

[Brid]

There are lines on the case inner that you can measure the pick up brackets against. All good fun.
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?)

[koko64]

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.

[clubhousemotorsports]

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.

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.

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?

[Brid]

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

[clubhousemotorsports]

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.

[ducpainter]

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.

[clubhousemotorsports]

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.

[Brid]

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)

[Brid]

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

[ducpainter]

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.