Just a warning to be very carefull with the valve cover seal. A customer with a kx250f 09 shimed the valves and when re-fitting the valve cover tightened it down with about 1" of the seal at the front of the motor popped out. Went for a ride in wet muddy conditions and after two hours the motor stopped. Pulled the motor apart today and found it to be full of grit. It has worn his cams and journals to the point of siezing the motor. Scored his cylinder pretty badly too and worn his crank bearings. Looking at least 2k just for parts. He is real bummed as you can imagine.