2004 crf250r no compression

[defo26]

Ok so to start off the bike hasent been run for about 2 years. It lost compression once and I had the head, valves, springs, all redone because the valve seats were bad and not sealing. I rode the bike about 3 times and one day it wouldnt start again (no compression again.) I checked the valve clearance and it was good. I ended up getting an 07 and the 04 has sat since. Well this past week i bought a new piston and installed it in the 04 thinking maybe the piston was bad. I had the cylinder honed and everything put back together. The bike still has no compression. I checked all the gaskets and they are good. Any other ideas?

 

[IndyMX]

While the head was off, did you check the valves to make sure the seats weren't leaking?

 

[defo26]

yup poured gasoline through and they were sealed fine

 

[_JOE_]

Can you get a pic of the cam at TDC?

 

[_JOE_]

Can you get a pic of the cams at TDC?

 

[IndyMX]

Yeah, it's very possible that the cam gear is not in time with the cam.. Had it happen on a KX250F last year.

 

[_JOE_]

That was my thinking, it's happened to a few people.

 

[wake_rider]

Exactly what I was thinking. It had to be a cam timing issue...