Could really do with some help here please.
I have an 08 450 EXC-R and have just started getting the oil transfer problem, gearbox to engine. The bike also smokes like hell after a downhill descent on closed/partial throttle or if it has been leaned over on the lefthand side (as you sit on the bike). It's definitely oil as its blue/grey smoke but it burns off within a few seconds of riding on the flat. It's only just started doing this but obviously it needs sorting, question is what is the likely cause? I'm assuming an oil seal has failed somewhere allowing oil to flow from the gearbox and the downhill angle combined with additional oil is forcing oil past the rings and it's then being burnt off - does that sound correct?
There's no noticable drop in performance so I don't think the rings are shot and the last value check (at 92 hours, now on 106) all values were spot on, albeit right at the minimum gap. I've read loads of conflicting stuff about these motors but hoped someone on here might point me in the right direction and offer any advice as to modifications and/or third party replacement parts that solve this problem.
Any help/advice would be very much appreciated.