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Discussion Starter · #1 ·
When I start the bike, The number 1 cylinder header does not get hot like the other 3. I checked the plug, It's fine. I checked the coil too, it's ok. When I had the header off, 2, 3 & 4 had carbon build up and the 1st was shiny. As if maybe fuel isn't being burned. The bike seems to run fine-just bought it though. Anyone know what could be the problem? I have the full akrapovic race system on it now too. I'm getting ready to put the Ivan's jet kit it in..But I'm a little worried about the number 1 cylinder. If anyone has any suggestions, let me know..Thanks.
 

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THE MAN
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how did you check the plug? hold it against the motor while you turned it over? if you did and it sparked then you did great :)

You need four thing to make an engine run, fuel, spark, air, and compression. That cylinder in missing one of those things, you need to figure out which. It should be the same heat at the same time as the other cylinders.

Clearly if it has no carbon in it, then it's not getting any fuel. Have to pull that carb apart and see why.
 

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Discussion Starter · #3 ·
Checked the plugs, carbs switched coils just to make sure wasnt a bad coil. Dont have a compression tester yet, what are the possible causes of this. Could it be bad ring, sticking valves???? Whats the best way to find the problem. I am 100% positive the fuel is being delivered in and gets spark please help.
 

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R1
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pull the plugs back out and put a rolled up paper towel in the recess where the plug boot goes. spin the motor over with the starter. the paper towel should come shooting out. if it does, you have compression and no sticky valves.
 

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I had a similar problem where cylinder 1 was running cold (about 80F cooler). My bike hesitated and ran rough under 2500-3000RPM and the power just kicked in and the bike ran smooth after above 3K. I took it to a shop and had them clean and adjust the carbs and it didn't help the problem. They said I may have a bad ECU or another electrical prob and it would be $$$ for them to trace it down.

I finally got fed up and did some research. I traced it down to a plugged pilot jet in the carb for that cylinder. It ran fine at higher RPM's because thats when the main jet kicked in. Just a couple quick hard sprays of carb cleaner cleared it up. Just becareful with the amount of carb clean you use because I heard it could warp the plastic in the carbs if you use to much.

Hopefully this helps. Oh yeah, change your fuel filter at the same time you do this.
 

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Discussion Starter · #7 ·
I had a similar problem where cylinder 1 was running cold (about 80F cooler). My bike hesitated and ran rough under 2500-3000RPM and the power just kicked in and the bike ran smooth after above 3K. I took it to a shop and had them clean and adjust the carbs and it didn't help the problem. They said I may have a bad ECU or another electrical prob and it would be $$$ for them to trace it down.

I finally got fed up and did some research. I traced it down to a plugged pilot jet in the carb for that cylinder. It ran fine at higher RPM's because thats when the main jet kicked in. Just a couple quick hard sprays of carb cleaner cleared it up. Just becareful with the amount of carb clean you use because I heard it could warp the plastic in the carbs if you use to much.

Hopefully this helps. Oh yeah, change your fuel filter at the same time you do this.
I took the carbs apart again and found the jet and there was some gunk in it and cleaned it and now its finally running hot and revs great. thanks for putting in your two cents r8ders.
 
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