Triumphrat

06-09-2006

hello,, this is my last call before giving up. there are some very sharp people here perhaps one of them may solve the issue i cannot define. it may be easier to read the diagnostic results posted by printing this post ..?? but first i will set the stage by explaining the symptom and what happened exactly.

at about 800 miles on my TBA i added aftermarket exhaust, once the stock mufflers were disgaurded it was evident that the right cylinder was not firing. the stock mufflers masked the engine noise so well you would have never known there was a problem. there is only 2149 miles on the bike wich is all from testing and tuning trying to find problem.
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THE SYMPTOM
right cylinder not firing, spark plug is usually wet, it will detonate now and again making a pop or misfire noise. you can plug off the right muffler with your hand and engine will not change continues to operate unaffected,,plug off the left muffler it will cough out and die instantly. i have fully inspected,gauged top end of engine looking for the issue.
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FUEL
LEFT CYLINDER-----------------RIGHT CYLINDER
stock carbs>> tuned out fine .....................would not tune
keihen cr's >> tuned out fine .....................would not tune

i am ruling out carb issue because it would mean two brand new carb sets would be malfunctioning on the right bank. doubtful at best, and the check valve breather line on fuel tank is free and functioning.
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ATMOSPHERE
LEFT CYLINDER-----------------RIGHT CYLINDER
compression>> 175lbs................ 175lbs
intake vac >> 12 psi ................ 14 psi
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VALVES
LEFT CYLINDER-----------------RIGHT CYLINDER
clearence>> in spec............... in spec
bent >> no................. no
leaking >> no................. no
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TIMING
LEFT CYLINDER-----------------RIGHT CYLINDER
timed from
manual >>>> cannot be incorrect on one cylinder
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COILS
LEFT CYLINDER-----------------RIGHT CYLINDER
swapped sides>> fires fine...................not firing
coils provide a nice blue spark, hardly weak
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P/U SENSOR
LEFT CYLINDER-----------------RIGHT CYLINDER
cannot malfunction on one cylinder and not the other , and once again coils provide nice spark both sides.
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IGNITER
LEFT CYLINDER-----------------RIGHT CYLINDER
fires fine....................not firing
once again coils provide nice spark both sides
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WIRING HARNESS
i have inspected several times,,connectors etc.
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CHARGING SYSTEM
multi meter shows 13.5 volts steady on battery leads when bike is running.
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i dont know where im missing the problem,, i have alot of hours testing and re-testing engine and systems. your probably thinking why didnt you go to a dealer for service? for me that requires travelling long distances and finding time away from work. not to likely in my world.

[ This message was edited by: fuelish on 2006-06-09 08:53 ]

Mojoinco · 06-09-2006

Sounds like either the pick up (don't know how bonnie's are laid out) or the ignition module. Not too many other components. on old bikes, you have to push/pull/twist near pick up (inside the case) to figure this out (on old bikes the pick up carrier moves when the timing palte advances) if it is a wire. Can you swap the pick up coils (same idea as swapping the ignition coils)?

vinnyf · 06-09-2006

Cheers, fuelish - sounds like you've done a really good job of checking and diagnostics. From the fact that your plug is wet, you know fuel is getting there, you've got compression, and you're making a good spark. Only question is WHEN is it making a good spark - for some reason, it's obviously not igniting your mixture. I don't know what these are using to actually fire the plug, but I'd tend to agree with Mojoinco about possibly the trigger; I'd be much inclined to believe your problem is electronic. Happy troubleshooting, and please keep us posted.

Stiles · 06-09-2006

I assume you've tried a new spark plug on the affected cylinder?

bigern2300 · 06-09-2006

It's pretty basic...
1. Do you have 12 volts to the coil?
2. Is there good conituity from the other post on the coil
to the ignition module?
3. Have you Ohm'ed out the affected spark plug wire to
check for a degraded/ damaged spark plug wire.
4. Tried a fresh (new) spark plug?
Try something as simple as swapping the plug wires. You say you've swapped coils and the affected coil will fire on the left side wiring, but did you use the left side plug wire and spark plug when you placed the right side coil on the left side?
It could be somethig as simple as a faulty plug wire or spark plug. Good luck

06-09-2006

will make more checks in the morning,,,

[ This message was edited by: fuelish on 2006-06-09 23:13 ]

Jhumphrey · 06-10-2006

When you say you checked the timing, Im assuming that you lined up the timing marks on the cam shafts and the correct timing marks on the crank sensor to verify everything was correct?

06-10-2006

the shop manual was a bit expensive but i do have it, setting the engine time was not at all difficult.

whats really interesting here is i went down BIGERN2300 list of electrical checks last nite and everything passed with flying colors, im not suprized this has been the way it is from day one. that pretty much concludes everything what else is there?? plauseable theory time: an out of tolerance or defective cam lobe ??? defective head casting ???

Wombat · 06-11-2006

Quote:

On 2006-06-10 08:13, fuelish wrote:
plauseable theory time: an out of tolerance or defective cam lobe ??? defective head casting ???

Neither of which will cause the no spark issue.

From your diagnostics, it sounds to me like an ignitor box problem.

06-11-2006

hi bob,,
by your location it must really take motorcycle riding up a few notches for enjoyment. my post is lengthy and easy to confuse the problem, thanks to bigern2300's tech list i proved what i believed all along. its not electrical but mechanical (somewhere), i believe the ignition system is firing strongly on time. for some reason detonation will not occur in the right side chamber with everything it needs: compression, fuel,spark. all roads lead back to the head and valve train, i would bet the farm if i changed them out the bike would be fine. to simply purchase these items new and put the bike back together i have priced out the parts to equal 50% or more of the bike price new. time is my only friend now, perhaps a wrecked bike or parts will present themself in the near future. for now deep storage looks to be at hand.