Its not happening on a yamaha, but this problem is not brand specific. I replaced the rings & piston on my brothers bayou and after assembling everything the bike shoots air out the air box instead of sucking it in and the hose from the air box to the carb is drenched in gas. Someone on another forum mentioned the carb being faulty but its costs $280 [img]i/expressions/face-icon-small-shocked.gif[/img] and id like to get other ideas before spending all that $$$$ on a part that might not fix the problem. Help !!!! [img]i/expressions/face-icon-small-confused.gif[/img]

 

If it was a 2 stroke I'd tell you the piston is in backwards, but the bayou is a 4 banger. right? Sound like someone royaly screwed up with the valves. Like it is using the intake valve for exhaust? I don't know what I'm talking about.

Long live the 2 stroke!!!

 

I didnt touch the valves, just replaced the piston and put everything back together. Now its spitting out instead of sucking in.

 

Did you pull the timing chain to do it? I would think you would almost have to to get the head off.

If the timing chain hasn't been realignined perfectly, they you're going to get the problems your talking about.

Brad

 

You put the engine in backwards fool! I would check the valve timing, if the intake vavle wont close, it will shoot stuff back up.

 

More specifically, if the intake valve is open during the exhaust stroke.. it's going to push gas/air back up through the carb

 

They're right. Sounds like cam timing. Get a service manual. If cam timing was off at one time, then the valves may be bent already. Good luck.