I am Helping a friend who traded for an 02 883. The bike had been sitting for awhile and the previous owner rode it a considerable distance with it back firing thru the carb. When I looked at it the First time the Carb was gummed up. It has been gone thru several times and is in good shape at this point. The intake gaskets were also changed.

The Problem: the bike will start and idle perfectly, even for extended periods. When you give it any throttle the accelerator pump will shoot the steam of fuel, the slide starts to rise and the RPM starts to come up. At this point the engine will not come up on RPMs and the carb slide will start to rise and fall a small amount but rapidly. THEN the engine back fires thru the Carb, Flames coming out of the carb.

The Compression is strong and every this else seems to be working good, The engine will not come up on RPMs without the severe back fire and then it will eventually die.

Any thoughts on what it could be would be greatly appreciated.

Thanks,

Al

 

have you checked the ig. timing?? sounds like the timing is off..

 

Timing or a floating lifter.

Did you actually do a compression test?

May even be the valves not seating completely.

 

I'd suggest that the vacuum diaphragm on top of the slide needs to be inspected. Sounds like the slide's trying to rise, loses vacuum, and then is falling back, as indicated by the slide "float" you observed.

 

Replace your vacuum lines and check the V.O.E.S.

 

Yeah, I agree with 1984_FXRT on this one. It, as you said, the carb. has been taken appart several times, the float diaphragm could very well be damaged. It is also one of the easiest things to check.

 

+++ to what already has been said. Adding: a camshaft with wrong timing can do it, too.

 

Thanks All for the input. Looks like i have a few avenues to go down. I will update when i know what the issue is or if i am still having troule.

Happy Thanksgiving!