Motorcycle Repair: 82 honda xr 80 dirt bike, honda xr 80, honda xr 80 dirt bike

Question
im haven a real hard time tryn 2 time this honda xr 80 i put a whole new top end on it. new carb. it a little cream puff but need help timing the thing and also what is the gap suppose to be between the vavle and the rocker arm  im thinkn its .008" but not sure i still have to adjust the vavles and timen

Answer
Andrew, When you put the timing chain back on, the piston needed to be at TDC (T mark on flywheel) and the cam lobes downwards so both valves are closed. There are marks on the camshaft sprocket that would align either with being parallel with the cylinder head or a single punch mark that would be at 12 o'clock position.

http://planetminis.com/forums/vintage-honda-xr75-jdm-vertical-motors/152407-how-

http://acsracing.tripod.com/mxracing/id39.html

If you didn't get the camtiming set perfectly, then there is a chance that you can bend the valves when the piston hits the valves due to being out of synch.

Valve clearances, as noted in the above links is .002" when both valves are closed on TDC compression stroke.

Bill Silver