ummm the prices have went UP or have you not checked in the past couple weeks.... topend rebuild kits are $60 plus shipping from
www.gasbike.net
the hardest thing to rebuild one of these kits is getting the new circlips into the new piston
there is no timing chain or valves to set the backlash on....
the timing is preset....
order a new set of cylinder studs of
www.sickbikeparts.com
grab a torque wrench from
www.harborfreight.com one of the 3/8s or 1/4 inch drive torque headstuds to 12# of torque
if you have to you can drive the piston out of the cylinder using a chunk of wooden dowel thats 1inch round or so cut spacers from wood to put between block and cylinder
the more you drive the piston down in the cylinder the thicker you need to make your spacers
make note of where the little arrow on the piston points so you put it back togather
..oh and when you add straight gas to premix you change the ratio of the amount of oil to gas and leans it out so it goes....MELTDOWN AND BOOM...then you walk home or pedal when disconnect the chain