Backfiring through Flywheel Cover

Okay, here's the deal, i been having lack of power issues, exhaust prob plays a huge role in this, stock pipe is all gummed up i believe, but today, i noticed(cold out, choke on, jsut started it) it was backfiring out the flywheel cover!!! Put head down there and sure enough, every few seconds, I heard "Poof". ANy ideas??? Lots o miles, no idea of condition! ANy help greatly appreciated. It's a 125 2-stroke by the way

The crank seal on that side is shot

Agreed, you can replace the crank seal without splitting the cases. You will need to remove the flywheel cover, flywheel, and stator. Not hard to do at all, but I would recommend buying a flywheel puller (~$10 - $15).

The easy way to remove the seal is take a self tapping screw and screw it CAREFULLY into the middle of the seal. You can put another in on the other side if needed. Then just take a pair of vice grips or pliers and grab the screw and it will pull out the seal.

Lightly grease the new seal and press it back into place. Make sure you don't install too far, it should be pretty close to flush with the outer case surface.


sweet!, thanks guys

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