I had a xr50 engine laying outside for prolly 2 years decided i wanted to fix it. i re honed the cylinder put it back together and i had no compression at all. figured i had pitting in the cylinder so i got an 88cc bore kit, installed it and my fiddy still has no compression, i dont know what it could be or what i did wrong. Can anyone help me out?

 

if the valves arent adjusted right or they dont seat right you will have no compression ..

valve lapping compound will clean up the seats if they have a small amount of rust or corrosion keeping them from seating ..

 

ok, looking at the valve stems they deffinatly wernt seated. i tried lapping the valve to where i left they seated fine threw it back together and i have compression of 30 psi but bike still wont kick over, should i try lapping them more?

 

i dont know what the psi should be on that bike but the valves should be water tight when they are seated properly