Could ues someone else's experience

In a nut shell, have an 2004 CRF 250X. Top end sort of (didn't eat a valve) crapped out. Turns out the cam bearing gave out and lost a shim. Shop that worked on it didn't find any top end damage and replaced cam with a hot cam stage one, something else I can't remember and reshimed as they said the intakes were tight. The bike started perfectly before the work and crap out. Here is the issue, the bike won't start at all without choke and then only when the ambient temp gets above 80 degrees. Even then I have to roll the throttle up a crack to catch. I have been up and down the slow jet sizes as well as the main jet. Once the bike starts, it runs well, although it is way to rich right now. Does this sound like a valve issue or perhaps a carb circuit issue? What other circuit affects starting besides the slow jet? Obviously, it isn't getting enough fuel without choke on and the ambient temp being up, but the fact it runs fine once it does start is a mystery to me. HELP!

It sounds exactly like a leaking intake valve issue.

Re-inspect the intake clearances, and shim if possible, but a 2004 X with the stock valves is undoubtedly in need of head work.

45 pilot

160 main

NCVS needle

Uncorked airbox and exhaust

Edited by Krannie

It sounds exactly like a leaking intake valve issue.

Re-inspect the intake clearances, and shim if possible, but a 2004 X with the stock valves is undoubtedly in need of head work.

45 pilot

160 main

NCVS needle

Uncorked airbox and exhaust

It sounds exactly like a leaking intake valve issue.

Re-inspect the intake clearances, and shim if possible, but a 2004 X with the stock valves is undoubtedly in need of head work.

45 pilot

160 main

NCVS needle

Uncorked airbox and exhaust

Thanks, I was leaning toward that with it being that year, since the guy JUST reshimmed it, I thought maybe it was carb related. I bet he didn't shim it to spec as I mentioned it started fine before he worked on it. Unless there was valve damage after the crap out, which I would have thought he would have seen when he was in there.

Did it run for a little bit when you got it back, or did it not start right from the minute you got it home? If it was wrong from the minute you got it home, he probably messed something up. If it ran for a little while (like 1 ride), then got hard to start, you probably need valves. You said that the intakes were tight and he re-shimmed. Once you re-shim with these titanium valves, they will move again VERY quickly. Once the titanium coating wears off, the valves are toast. Pop the valve cover off and measure clearances, let us know what they are.

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