Crf250r Won't start?

I had a long day riding at haspin acres today with a few buddies. I killed my bike to take a lil break in the trails and it never would start back up. I have no idea what happened! The bike does have a Rekluse, so that keeps it from stalling out, I got back home(hour and a half drive). It never started when I got back home either. Any idea??

Check intake valve clearance.

You need compression , spark and fuel. Check all of these and you will find the problem. If the bikes has lots of hours on it 

I would say its ready for a top end rebuild. If the valves are starting to move there is very little time left in the top end . Sell it or rebuild it.

try bump starting it. and check your fluid levels especially the radiator coolant.

If its got a rekluse, then he can't bump start it...

The bike was rebuilt at the end of November last year, never raced. There's no way I need a rebuild at this time. I also have another bike that I ride more and race it.

The bike was rebuilt at the end of November last year, never raced. There's no way I need a rebuild at this time. I also have another bike that I ride more and race it.

I would still check the valve clearance... It's so easy and such a common problem

As stated, you're going to have to check for spark, compression and fuel. We can't tell you through a keyboard what's wrong without having more info. You're missing a part of that equation. Report back with what you find and go from there.

I finally got my head back, I sent it off to FinishLine Engines and he replaced all four of my valves, shimmed them and replaced seats (had everything done). Got my bike all back together... New plug, new valves, in time, gaskets, has compression. The bike will not start? It is trying to fire but it just won't start. If anyone has any idea just say something...? Thanks

Off one tooth on the cam timing.

One tooth off on the cam chain? Meaning it is out of time?.. One tooth can keep it from starting?

Yes, it can make it hard to kick start, but can usually be bump-started.

How did you verify cam timing?

Edited by Eddie8v

That's it then!! It is a bear to kick, I figured it was like that because of the new valves. Now on how I timed it... The right side motor I lined up a notch with the not on the gear to get it too dead center and then I lined up the two lines on the can with the head.

It's hard to do it that way, you need to remove the left-side case plug and use the marks on the flywheel to verify TDC then check the cam sprocket marks. I think the explanation on how to do this is at the top of the forum in the "stickies" or maybe the CRF450R forum, same principle. When rotating the motor you use the second hash mark as TDC vs the notch in the case. Very simple.

What are the valve clearances?

Edited by Eddie8v

The bike is at top dead center for sure now! Still trying to fire but won't? Has spark! What do you think it would be?

Do you mean the cam is properly timed to TDC on the crank? Was it off before?

What are the valve clearances?

Edited by Eddie8v

Yes, the cam is timed at top dead center with the crank. It was never off I just double checked it...

What are all 4 valve clearances? What's the spark plug look like?

The head was just fully rebuilt with all new valves, mean shimmed in specs. An brand new plug.

Just measure the valve clearances. A rebuilt head is only as good as the mechanic who worked on it and assembled it. You need to eliminate that as a cause, please.

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