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Discussion Starter · #1 ·
hey ive got one cyl not firing when i am idling. ive never removed the motor, but could it be a timing problem, when i unseized the engine by turning it from the crank shaft access hole in the front of the engine?
 

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CDI timing is fixed so ign. timing is unlikely to be your problem. I doubt if you've put your timing out by turning the motor.



Probably carbs or a spark gremlin.



There's experts here on both systems and they'll tell you all you need to know to find and fix your problem.



I've seen some other posts that suggest you have already had a number of problems with this one so maybe a quick recap on what you've already done to this and why would help us to help you.
 

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If it fires both when you throttle up, but only one when you let it idle, it's most likely somewhere in that carb. I'm by no means one of the "experts" that CXPhreak referenced, but that'd be where I start looking. Good luck with it!
 

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More than likely you have a plugged low idle jet in that carb. The jet is under the rubber plug in the center. Clean it out with a .018" drill bit like illustrated in the cutaway picture.





The other possibility is the inside of the plug caps. If there is corrosion in there they won't deliver all the spark needed to fire at lower RPM's. Plug cap repair.
 

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More than likely you have a plugged low idle jet in that carb. The jet is under the rubber plug in the center. Clean it out with a .018" drill bit like illustrated in the cutaway picture.





The other possibility is the inside of the plug caps. If there is corrosion in there they won't deliver all the spark needed to fire at lower RPM's. Plug cap repair.


Had the same prob when I first got my CX, it was a dirty plug cap as Larry mentioned.
 

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Discussion Starter · #6 ·
yeah ive never cleaned thous i'll give them a good scrub down. i have cleaned the carbs several times in the past 2 months so im really certain its not carb related.
 

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For what it's worth, I was thinking firing from your initial post. I sure have seen it plenty of times. My usual drill is clean from one end to the other, replace plug, replace plug wire.
 

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yeah ive never cleaned thous i'll give them a good scrub down. i have cleaned the carbs several times in the past 2 months so im really certain its not carb related.
Shorty,



Unless you have read Larry's carb book and used an ultrasonic cleaner to clean them it probably is the carbs.



You really needs to understand the forum rarely gives out the bad advice.
 

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Seized engine? Yikes. New plug fixed my misfire at idle problem immediately. The second thing I would do is do a compression test. Most motors should have no more than 10 or 15 lb difference. Low compression would cause hard starting or missing on a bad cylinder which would end at higher rpm's. Do the simple stuff first!
 

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Discussion Starter · #10 ·
update,

i cleaned the terminals and resisters on the plug caps. and there was a great improvement, also i had a tear in the left rubber cylinder boot just after the tightener clamp. it was making this horrible sucking noise i repaired it and by fixing both the spark caps and the tear it can actually idle lower then ive ever had it before.



but it still only allows me to idle on the same one cylinder. when throttling up gradually, i still get an almost dragging, sensation. and if i crank the throttle it makes a starving thumping lugging feel to it.

would the length of the spark plug in the cylinder play a part. or does it sound more like another vacuum/carb problem.
 

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Discussion Starter · #11 ·
oh just to clear up, it runs fine out of idle. and when i crank on it it takes 1-2 seconds to fire on the second cylinder when the rpms high enough
 

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yeah ive never cleaned thous i'll give them a good scrub down. i have cleaned the carbs several times in the past 2 months so im really certain its not carb related.
i think it is carb related....can you elaberate how you scrub your carbs....the process and how long it takes?
 

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Discussion Starter · #14 ·
with carb and brake cleaner, i take it down to every piece. except of course the pieces that need taken out by reverse drill bits. i clean them till the crust and grime is off. the strange thing is that i have had 2 sets of carbs in this bike and the problem is very similar, almost identical. both carbs had problems on the right carb and it was the same no idle at low rpm problem that persisted. its strange isnt it. might be coincidence but it might not.
 

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If the carbs are out of sync enough you will get a cylinder drop out at low idle. Upon throttle opening, the "dead" cylinder picks up.
 

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with carb and brake cleaner, i take it down to every piece. except of course the pieces that need taken out by reverse drill bits. i clean them till the crust and grime is off. the strange thing is that i have had 2 sets of carbs in this bike and the problem is very similar, almost identical. both carbs had problems on the right carb and it was the same no idle at low rpm problem that persisted. its strange isnt it. might be coincidence but it might not.
just read all the posts in your thread.

have you tried swopping over the spark plugs.......its a long shot,other than the carbs,,,mmm

how long did it take you to clean/scrub your carbs?
 

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Discussion Starter · #17 ·
about a day. my problem cyl was black. but i bet thats because of my pod filters (removed them last week), i cleaned it really well and another improvement happened, the delay on throttle pickup had reduced. the thing that bothers me is that when i let off of the throttle it takes a 1-2 second delay to return to its idle
.
 

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about a day. my problem cyl was black. but i bet thats because of my pod filters (removed them last week), i cleaned it really well and another improvement happened, the delay on throttle pickup had reduced. the thing that bothers me is that when i let off of the throttle it takes a 1-2 second delay to return to its idle
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PODS?........
problems incorperated



i was thinking and could all these delays be a tired cdi?
mmm,does the cdi only work on one pot,and then piss off the other,i doubt it
 
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