Random misfire or backfires on one cylinder.

[setasai]

Hey, a buddy of mine has a suzuki intruder that has been giving him issues. I've attached a soundbyte recorded by my cell phone so it's not the best quality but it should give you an idea of what it sounds like. You can use quicktime to listen to it.

Basically, it makes this randomized nonrhythmic popping sound. Kinda sounds like popcorn in a microwave. We've narrowed it down to one cylinder because he has a twin exhaust that doesnt connect and I can tell which it is coming from.

Things we've done, cleaned out his airbox and cleaned out every jet on his carbs... both of them. Also new gas but that shouldnt make a difference. Like I said the issue is on one cylinder and is most prominent just idling. When riding, it backfires/misfires and the whole bike jerks like a bronco.

He has taken it to one mechanic already which was useless because they didnt even take the carbs out to clean it. We know this because we took it out and one pilot jet was completely clogged and the float bowls was completely broken on the other carb. Fixed both issues which made the bike run better but still this one last issue.

Ideas? We're going to take it to another mechanic that I trust this week but any ideas or directions would be super helpful.

Thanks in advance.

[DaBlue1]

Did you sync the carbs?

[setasai]

Originally Posted by DaBlue1

Did you sync the carbs?

Oh that's a good one. No we did not. Will look into that.

Would the carbs all of the sudden go out of sync? I ask this because it was fine and then one day it just started going wild.