My 05 crf 250r will only start when pull started

I have the same problem you may need to shim valves this only takes about 20 mins if you know what you are doing you will have to look up all the clearences then go to honda order them trow them in and see if it will start. And also i donk know it this is possible but you kick start may not be catching or something like that. hope i helped

It's your intake valves honda uses a titanium intake valves while it saves .999 pounds it IS there down fall. The valves start to recesse into the head, which we know will cause the clearance to get smaller. A.P.E offers a great fix, its a rebuilt head port and polished to stage 2 specs. with stainless steal valves springs and new keepers. While your there it'll give you a chance to see how things are doing on the top end of your motor, pull your cylinder and check your rod the gasket kit comes with a base gasket too so take your and build it right. this is also a great to replace your rings and hone the cylinder or better yet put a bore job on the to do list.
Fix it right, Ride it fast!
Mark
C.C. Motorsports