I recently installed a 70cc airsal cylinder kit on my '77 puch maxi. I have a 15mm bing that was jetted to 82 with an intake and exhaust on the bike. After about 100 miles...i hear some metal noise then blurp...bike stops...won't start. push it home 4 blocks and pull it apart...the cylinder/piston are thrashed. Massive amounts of scoring on the bottom side of it. Mix ratio was 40:1. Any ideas? Is this common with this kit? I know i need a new cylinder/piston kit, but damn...$120 down the tubes.