The last two pistons on my bike have had a very short life (maybe 15-20 hrs tops) and they end with the engine siezing up. I'm assuming something is wrong with my jetting causing it to run lean. Also having some trouble with my idle which might be related. Once I have the engine warmed up and running for a bit it has a really high idle. When I initially start the bike and warm it up before i get on the track it idles fine. While riding the bike soon before it siezes it sounds like what I would sort of describe as a "tearing" sound coming from the engine. Running 40:1 mixture. Any ideas what could be wrong? I just ordered a new top end so I'll be replacing it this week but I need to figure out the cause of the problem. Thanks!