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Hard starting CRF250x

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I've got a 04 250x that has been a little hard to start. Cold will not start with e-start but if I hold the throttle about 1/2 open and give it a good kick with the choke on it'll fire up and then once warm it still requires a little throttle but will start with the e-start. I've cleaned filters, carb, tried a richer pilot jet not change.  Have yet to checked valves yet, were done less than 20 hrs ago and I never hit the limiter  

Any Suggtions ?

Edited by MotoGriff

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The engine has an auto compression release and from my experience anything that further reduces compression will cause hard starting, any one of the following, or a combination:
Tight intake valve(s)
Worn timing chain.
Worn, or new, rings.

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Yep just checked the valves. One intake valve was in spec the other has 0 clearance...guess I'll be shimming valves in the morning instead of riding.  With it being at 0 clearance will shimming do any good or will it just go back to zero after a few rides and I need new valves?

Edited by MotoGriff

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Don't know how long your bike  took to go to zero, but I had a similar problem with the right intake on my X.  I rode it all summer/fall :banana:by reshimming the valve a couple of times; on the last reshim I had to grind a shim to make it thin enough. I redid the top end that winter.

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On 9/4/2017 at 1:41 AM, MotoGriff said:

I've got a 04 250x that has been a little hard to start. Cold will not start with e-start but if I hold the throttle about 1/2 open and give it a good kick with the choke on it'll fire up and then once warm it still requires a little throttle but will start with the e-start. I've cleaned filters, carb, tried a richer pilot jet not change.  Have yet to checked valves yet, were done less than 20 hrs ago and I never hit the limiter  

Any Suggtions ?

Had one just like yours , sell it and get a TWO stroke man

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What KeyKeeper says.

I've done the kibblewhite intake replacement on 2 of my friends bikes, as well as my own.

That was 200 hours ago on mine. No noticaable performance difference. I think I have made slight adjustment on 2 valves in the last 6-7 years.

Replacing the Ti intakes with steel makes the crf250x a really great bike.

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On September 3, 2017 at 3:41 PM, MotoGriff said:

I've got a 04 250x that has been a little hard to start. Cold will not start with e-start but if I hold the throttle about 1/2 open and give it a good kick with the choke on it'll fire up and then once warm it still requires a little throttle but will start with the e-start. I've cleaned filters, carb, tried a richer pilot jet not change.  Have yet to checked valves yet, were done less than 20 hrs ago and I never hit the limiter  

Any Suggtions ?

I've owned an '05 CRF250x since new (12 years now) and have ridden it about 2000 miles a year (it's streetlegal and has a license plate). Up until today, I hadn't had an engine cover off it yet. Never even checked the valves. About 4 years ago, it began to become more and more sluggish to start, but it always did start with the Kickstarter and ran normally, until recently...

I've been riding it on the road a lot this summer, sometimes 30+ miles at 60 mph, and after yesterday's 60 mile ride to the Albany Supercross track and back home (and riding a bunch of laps at the track), it would no longer idle or start without bump starting it...

So, today I check'd the valves for the first time. Both exhaust valves were right on spec, at 10 thou each...both intake valves had zero clearance (actually less than zero, I think). Not wanting to wait till tomorrow to finish the job by driving 60 miles round trip to the local Honda dealer to get thinner shims, I just sanded the shims down from .075 to .069, re-installed the cam and re-check'd the clearance and saw it needed a little more taken off, so I removed the shims and sanded them down to .064, re-installed them and now the intakes are at .006.

When I put it all back together and hit the start button, it fired up and Idled like it did when the bike was new...

I think I'll remove the head this winter and replace the intake valves with the KW SS ones recommended by the wise, experienced 250x owners here on thumpertalk...

Randy

 

 

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