Hi there having real problems with wr450 03. Did 04 starter mod , after bike backfired and sheered stater. After mod still having problems bike backfired the other day and blew the rubber rockerbox gasket out on one side. Got that sorted. Headed out on bike again and this time it has sheered starter from back of flywheel Assembly and damaged stator.I am wondering is the bike running a bit weak though it doesn't bikefire just the odd time. I have a doma e series pipe on bike only thing I have done to it.I bought bike secondhand and have been speaking to Yamaha dealer he thinks it may be a European import, I am in UK and jets should be changed for our fuel. Does this sound right, anyone got any ideas. What jet should I put in, should I go for JD jetting kit.I am at my wits end, love the bike cant afford to keep throwing money at it like this.