hi,

A friends Nc30 is using alot of oil
Ive taken the carbs off and looking into the motor theres oil on the valves
Is this just a sign of valve stem seals or is it more serious
The bike seems to be goin fine but struggles to get to 160km/h

Thanks

Can you do a leak down test?

I have the same issue (1l/1000km of oil consumption at 150km/h, 6.8l/100km fuel consumption, underjetted to 112/115 to compensate for excess oil burning) although mine goes over 185km/h but it's down 10 horses on the dyno. When you do the leakdown test take of the carbs and listen or feel for air escaping from exhaust, intake or crankcase breather.

No, i cant do a leak or compression test at the moment