Trouble Getting Going

[ChrisK]

A few posts ago I said I went and bought two new plugs. Their sparks look the same now.

I believe when I was getting a weak spark it was because that plug was way fouled. But maybe I'm wrong?

[ducpainter]

A few posts ago I said I went and bought two new plugs. Their sparks look the same now.

I believe when I was getting a weak spark it was because that plug was way fouled. But maybe I'm wrong?

A few posts or pages?

Could be...

did you swap plugs from lead to lead to see if the issue changed to the other plug

I guess what I'm getting at is you've had a few different things going on since you started jetting.

You really need to make sure all the ancillary issues are resolved before you drive yourself nuts...including a compression test.

[ChrisK]

Anyone know the thread of our plugs, I'll try and get my hands on the right compression fitting.

[ChrisK]

DP, I switched the old plugs' wires and the spark followed the plug, not the wire. New plugs create equal-looking spark. So I think that's resolved.

[ducpainter]

Anyone know the thread of our plugs, I'll try and get my hands on the right compression fitting.

I believe it's 14x1.25.

I'm positive of the pitch. Check the diameter with your calipers.

[ChrisK]

I cannot believe that between three auto parts stores and a hardware store I can't find the right fitting for this.

[krista]

Hey everyone, just found out about this thread. Been so busy lately, I don't get to troll forums any more.

A question I just thought about sitting here: The FCR's came with a small fuel filter at the end of about 6 inches of fuel line. You take your existing fuel line and hook it up to the upstream end of that filter. Is it necessary to have both your original filter and that smaller filter? Could that be problematic?

I added those after we got lots of complaints of the FCRs overflowing into peoples' engines. Old fuel systems shed tiny bits of plastic-bag-like stuff which gets caught in the needle float valve and prevents the needle from closing on the seat. Started adding the filters and no more calls about flooded engines.

I don't think the clearances on the timing pick ups would have changed since I didn't take them off their bracket, and I reinstalled the bracket exactly as it was before.

I've only done like 4 or 5 carb'd flywheels, but that is absolutely a wrong assumption. There's way too much play with the plate's mounts to the engine case to get repeatability.

Setting the 'gap' of the triggers:

Whenever making any adjustments to the plate the pickups are on, you need to iteratively perform the above procedure until both pickups measure 0.027", rotating the engine back and forth.

You cannot adjust the front one then adjust the back one and call it done. You have to then re-check the front one (and it will be off).

My experience was having to go back and forth readjusting BOTH 3 or 4 times until both will measure 0.027" with the nuts fully tightened. I remember once or twice it wasn't so bad and I also remember it being maddeningly difficult and wondering if I was ever going to get them both close enough.

The very last time ever I have messed with one of these plates was a decade ago when I did the full 100hp recipe for a customer. I adjusted the timing 4 or 5 times trying to find the right balance of starting but able to still run. Ignitech saved my butt on that one.

My experience with the boxes is either they work or don't. I never had one that was making a spark cause any issues.

I've seen them idle ok and then go away as they advance. But it was pretty obvious on the timing light. Also, the bad one idled more weakly than normal and that cylinder's header pipe wouldn't immediately "steam off" when we sprayed water at it. With good ignition, it's difficult to see any damp spots on the pipe when you use a spray bottle on it.

Off the top of my head, stop changing 4 things at once.
Change one setting at a time, and see what it does.
Write down the settings, change one thing, write down the results.
Then try another change, continue writing it down as you go.

THIS. I read all twelve pages and frankly have cringed more than a few times.

Ca-Cycleworks jets for a basically stock intake set-up if I'm not mistaken. Small changes in configuration can make a difference, so every bike can benefit from some tweaking...some benefit more than others and some need different jets.

The Sudco baseline setting we use assumes aftermarket mufflers and you cut the airbox lid.

Where the "small changes" come into play however, is that I've seen bigger differences bike-to-bike than individual mods. The fact FCR's baseline works so well rests in that each carb is basically on a nice big dirtbike engine. Lots of flow and really high velocity through the intake port.

I understand one jetting setup isn't all encompassing for these bikes, or any for that matter. What I'm saying is that in my order notes, when purchased from Ca-Cycleworks, I specified that my bike was a 98 900 with W heads, had on open air box with K&N filter, ExactFit coils, and really free-flowing slip-ons. I was under the assumption Cycleworks would take into account the details I gave them and jet my carbs with those details in mind. Too much to ask I guess.

Yes, too much to ask because impossible to deliver.

The last time I was personally involved with a bike where mentioning all mods would make a difference was when the Kawasaki ZX6R first came out. The "big four" makes their bikes amazingly consistent. Muzzys figured out the exact thing to make an all-stock zx6r run awesome with their pipe and it was simple stuff like shim up the needles with washers and drill out the slide vent holes with a specific sized drill bit.

Ducatis are all over the map. IMHO, the big thing with the 90s era heads is that curved intake port. It acts like a huge restrictor and sets a standard for the flow through the engine. Those are all hand ported and I believe some engines get a little more or less love and will need the TLC after putting on FCRs.

Another aspect we don't see a lot is how well Ducatis run when things badly set up. Stuff we all assume is perfect like on pongo when the cams were timed 10 ~ 12° different from each other. Ducati's genious is actually how well their bikes work with sloppy tolerances and how the engine just doesn't care and keeps making us happy. This is exhibited in how well the FCRs work for people with the baseline Sudco and Pro Italia came up with 23 years ago.

I ended up going with OEM equivalents from a company called Jets-R-Us in Missouri. $3.19 for the mains and $4.67 for the slows. Brought the total to $47~. That's much easier to swallow.

BTW, we have jets if you ask. We don't list them on the site because it tends to make people want to change too many things.

Just a related line of thinking, I tuned a 900 with FCR39s, that went from 62s with V cams to needing 58s with 900 ie cams. It's making me wonder about the W cams. I need to ask Chris Kelley if the 60 slow jet in FCRs is a SUDCO setting or based on what Pongo needed when it had W heads. Maybe he might see the thread and chime in.

Actually, pongo never got the dual FCRs. He went from mikunis on an all stock engine to the full-on 966 build with single FCRs, which use a wholly different baseline.

NGK 9s are generally too cold, but the Exactfit coils are pretty hot if you got 'em and they can work. (Check with Chris Kelley).
60 slow jets are often too rich, add a too cold plug and you'll have fouled plugs and sluggish performance.

I was (and am) a staunch believer of the D8EA. They worked awesome on stock bikes like my ex's 900ss/cr and m900ie that she put 45k+ miles on each. They worked killer in my 900ss, `96 916, pongo, and my S2R800. They work killer with the Dyna coils that we used to sell, too. Non resistor plugs have been shown to consistently add 1 hp over their resistor equivalents.

Allegedly compatible plugs are the DP8EA-9, DPR8EA-9, DCPR8E. The P means projected insulator. What that means is the tip sticks out further in the combustion chamber. Once I talked to someone and found out high comp pistons can bump them and close the gap, I quit using the P type plugs.

Of all the snake-oil stuff I tried in the 90s on my 900ss, dyna coils, new wires, and non-resistor platinum plugs "felt" the best.

When we had the ExactFit coils made for us, they actually made the coils too powerful and then we could actually observe the wives tales about heat range, suppression wires, and resistor plugs. The dyna coils worked great with the stranded wires and D8EA plugs. So we ship our coils with the DR9EA. I normally advise folks to not change the coils at the same time as making other big changes. There have been a couple people where for whatever reason, our coils just won't work on their bike. I carefully diagnosed a few of these situations, too.

OH... well there went a couple hours... back to the salt mine!
Chris

[koko64]

Thanks Chris
We know you're busy, so it was good of you to chip in. Always wondered about Pongo.
Cheers

[ChrisK]

I appreciate you taking the time to write all that out, I really do.

That said, do you have any suggestions for getting me back on a running motorcycle? The Sudco settings didn't even get me down the street.

I understand I still need to check compression. But until I get my hands on the fitting, can we just assume I have good compression for the sake of conversation? After all, I went 110 mph into a 20 mph headwind yesterday.

[ducpainter]

Did it have any more to give?

[krista]

I appreciate you taking the time to write all that out, I really do.

That said, do you have any suggestions for getting me back on a running motorcycle? The Sudco settings didn't even get me down the street.

I understand I still need to check compression. But until I get my hands on the fitting, can we just assume I have good compression for the sake of conversation? After all, I went 110 mph into a 20 mph headwind yesterday.

I couldn't keep up with the changes.

Can you re-post the info where you're at currently? Ie, what are the bike's mods? And can you write up the end of your logbook of changes and effects? Then with your current configuration? When I last went through this, here's an example:

Main	Clip	s-a screw	effect
155	3	1-1/2	----
160	3	1-1/2	3rd gear, 6000+ rpm better

It's really really tough for me to sift through posts and retain any info from one to next. I'm quite visual and after getting my face kicked in setting up the 2 servers over the last week, my brain is about worthless.

[ChrisK]

That was in 5th gear, and it was starting to feel a little sketchy to be going that fast in those conditions at night. Maybe, but not too much more I don't think. Should it?

[ducpainter]

If that was 5th you're probably close.

Answer Chris's questions and ignore me for now.

He might actually have some useful info.

[ChrisK]

Chris, of course. This thread has been incredibly long, I'm surprised most are still hanging around : )

I will get in front of a computer in a bit so I can carefully type out where I'm at. Might be an hour or two though.

[ChrisK]

Okay, here's a summary of what's been covered in this thread, leading up to the present. I'll number "major" events to try and make it easier on the eyes. Anyone who's been paying attention, if I miss something important, please let us know.

First, my bike: 98 M900 W-Heads. FCR41's, ExactFit Coils, DCPR8E's, open air box with K&N, OEM headers, Danmoto slip-ons (very free-flowing).

1. Tried to go for the first ride of the spring, bike wouldn't let me take off in gear. Eventually discovered I didn't have spark in one cylinder. Traced that back to a broken wire at the ignition pickup.

2. Went through a whole ordeal getting the timing reset. I believe it is within OEM spec right now. Dots were lined up with the lines on the pickups, WHILE the motor was at TDC. The pickups were set with a .6mm gap from the flywheel lump.

3. Spark plugs replaced with DCPR9E's based on advice of people here. Bike still wouldn't let me get rolling. Very hard to blame jetting at this point because the FCR's were brand new from Ca-Cycleworks and most importantly, over the winter I had my hands on a lot of different things. I lightened the flywheel and had an error putting the starter clutch back in, leading to that, it's bearing, and a couple other parts getting replaced. I had the clutch pack out, adjusted one valve back into spec, replaced timing belts, and that's about it.

4. Blamed fuel delivery. Bypassed vacuum petcock and OEM pump straight to the carbs. No go. Manual petcock has been installed and OEM pump appears to be working.

5. Only thing left seems to be jetting. So I start in on that. I will skip a lot of the different configurations I tried early on because, as so many have taken the time to note, I was changing too many variables at once. I've got 7 or 8 jetting configurations written down from what I remembered, but no notes with them. I will start listing the jetting configurations that I made notes on, per everyone's advice. There are some crazy variables, so pay attention!  

6. 165 mains. 60 slows. 5th needle position. 1 turn out on fuel screw. 1.5 turns out on air screw.
Used this as a baseline to start with based off someone's suggestion. Bike idled rough but didn't die. Sharp vibration felt right when disengaging the clutch in 1st gear. Cruising speeds (constant throttle) didn't deliver a completely smooth feeling. Accelerated to above 100 mph in 5th gear into a 20+mph headwind.

7. Only thing changed: 0 turns out on fuel screw.
A little better idle. Still has that sharp vibration. Was 'diving' on throttle pickup. So when I was at zero throttle coming into a corner, then tried to pickup the throttle a little, the bike would dive on me then resume power.

8. Only thing changed: .5 turns out on fuel screw.
Alright idle, not as good as number 7 above. Still has the vibration, slightly worse than number 7. Dives on throttle pickup but got a little better.

9. The previous three steps were done while it was 33 degrees F outside. I decided I would call it a night, and try it out the next day in the 50 degree weather. Which brings us to today. This is where things get crazy and stupid.

10. So I go home at lunch to get the bike out. Start riding and the bike is sounding pretty bad. The longer I ride the worse it gets, feels a lot like I'm dropping a cylinder then picking it back up again. Barely hobble home. Take the spark plugs out, one is black and one looks normal-ish. Theories about why start swirling. I go through three more jetting changes, that I have detailed notes for. I don't need to write those hear, I'll tell you why soon enough. At one point I'm trying to screw on a 160 main jet and the thing snaps in half inside the carb. Got lucky and got that out free of drama. People are telling me I really need to check my compression so I've been all over town looking for the right fitting to do so buck can't find it anywhere.

11. So finally. I decide to take the float bowls off to check to see if I have a stuck float. Don't think I do but what the heck, can't hurt.......

..... This is the latest news that no one else has heard: I pull the float bowls out, look down, and the slow jets are laying in the bottom of the bowls. They had come unscrewed and were just laying there.  
So that is why all the jetting changes I've made this afternoon since fouling that plug mean absolutely nothing.   What makes that happen?

12. 165 mains. 55 slows. 5th needle position. 1 turn out on fuel screw. 1.5 turns out air screw.
Bike started right up. Revs would "hang up" when I revved it in neutral. So I backed the fuel screws out to 1.5. Better but still hung up a bit. Backed them out to 2. Sounded better so I took it for a test ride. Started off pretty good getting down my street. Got out onto a 45 mph road and it was hiccuping quite a bit, not running very smooth. Idling fairly well. Seemed like power was good when I opened the throttle up, but cruising seemed to be problematic.

13. Your turn.