250X no start...

Helping a friend with his 04' 250X. Is a great bike, but all of sudden hard/no start.

Thought maybe a fuel issue, but a squirt of starting fluid in the airbox, and not even a pop.

Installed new sparkplug, cranked over eng. to check spark, kind of weak. I feel it's either the coil, or a timing issue with the "black box"

Does anyone have the ohm specs to check out the coil? I don't want to have this guy just start throwing parts at the bike, too much money to do so.

By the way, I checked valve lash, and just fine, no tight valves...


Try to push start the bike before you do anything else, if it starts but will not idle, more than likely the intake valves are bad or if it doesn't start more than likely the intake valves are bad. Bottom line if your CRF doesn't start or it's hard to start the first thing you check are your intake valves period.

I know the valve lash is correct, hard to believe the valves are leaking and losing compression. If the intake valves were tight or burnt, it should have popped back thru the carb when we used starting fluid...or thru the exhaust if it was the ex. valves

This bike is trail ridden, and not hard...

The valve lash may be correct, but if they have been shimmed several times, it may not matter. They may be shot anyway and not giving enough compression. I would check compression and eliminate that possibility. Might try to pour just a little gas in the spark plug hole and see if it fires. Old rule of thumb Gas vapor + spark = fire

Steer clear of starter fluid sounds like possible trouble. KISS Fuel & Spark check the fuel first. Does it flow freely out of the petcock? Carb clean and working properly? etc.

What is the history of the bike? How many hours? Has anything been tore down or changed recently? Valves been shimmed? The more details the better guesses you will get. Good luck :banghead:

Sure sounds like intake valves to me also. Mine just went thru the same thing. Turned out to be the intake valves.

5 of the 6 times mine wouldn't start it was valves. Wheels50 is giving you good advice. Try to push-start, if it runs, you need valves.

I'm going to do a leak down test on it tomorrow. I assume when the valves go bad, they don't seat correctly...

Ok....checked the intake valves, and guess what? No lash.

Soooo we will be doing a valve clearence job. Nice sticky on this job along with photos. Will post if we get this bike started. Thanks to all that replied!

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