Banshee Backfiring

[Will910]

I recently rebuilt my shees whole motor top end and bottom, it started after a few kicks and died, then it almost started up but died, then I went to kick it after and everytime, instead of firing up the bike would backfire and shoot a flame out of the pipe.

[Surfrjag]

Fuel delivery problem or check the flywheel keyway

[Larry's Shee]

If you have a new crank you should lap the flywheel to crank to insure proper seating.

[Will910]

Ok, thanks will check flywheel key, and flywheel tomorrow, I have a +4 degree key and my stator has an adjustable plate, should the stator plate be set at +4 as well or at the regular position as stock, if so this may be the problem, I believe both are at +4.

[Surfrjag]

Thats probobly to much timing but i doubt that actual problem.

[tfaith08]

Take the flywheel off and use a normal key.  Then set the timing plate to your desired spec.  More than a few offset keys have sheared.

Backfiring is a case of the combustion partially taking place in the exhaust, caused by either an overly lean mixture that accumulates into enough fuel to combust or either the timing is far enough off for the mixture to ignite while the exhaust port is exposed.

[trickedcarbine]

Ok, thanks will check flywheel key, and flywheel tomorrow, I have a +4 degree key and my stator has an adjustable plate, should the stator plate be set at +4 as well or at the regular position as stock, if so this may be the problem, I believe both are at +4.

I'd start with getting a regular woodruff key. I'd assume you have a basic set up and that 8 degrees timing is a bit to much. Just to be sure, what are the motor mods and what fuel are you running?

[Will910]

I'd start with getting a regular woodruff key. I'd assume you have a basic set up and that 8 degrees timing is a bit to much. Just to be sure, what are the motor mods and what fuel are you running?

 

I have .80 bored over, porting , stock stroke and other bolt ons ,(pipes etc.) running r50 with 93 premium

Edited May 9, 2016 by Will910