05 crf250 wont start
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Got to agree with Joe, clearance and timing. Be glad you do not have 2 cams up top! And sadly, how well was the valve job done? If the clearances check out, you may need a leak down test to see how your top end is sealing up. Vintage Bobblanc said:
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update: full rebuild. rod.bearings, piston ss valves etc. we spent twp hours this eve re checking timing and valves intakes are a bit tight at .006 should be .009 however after a strip down we have found that spark is weak or non existant. back to draeing board all connectkons clean and look good
Timing, multimeter? Disconnect the kill switch first! You may be amazed what a dead draw does to the spark plug. Then we shall see if it will start at .006, when its supposed to be at least .008? Thats pretty tight. Vintage Bob
The mixture screw! No star for you today. But, yes it can make starting a real bugger? NOPE. The leak jet, choke circuit and probably technique are the biggest factor on starting, as long as its not something else. The thumpers since 05, tuned and it good shape, I've personally never needed the choke or hot start to fire up. 2 blips of the throttle and bam, worked almost every time. Except frozen or freshly crashed, then its another story. It started fine the normal method, but was cooler, less work. Vintage Bobbrad m said:
The FUEL SCREW does play a big role in these bikes starting. Mine usually stays pretty close through the season. I tuned it for around 1.5 turns out on the fuel screw. If you get more than two and half or three turns out the fuel screw it can turn itself out causing poor running or loss of the screw, spring, washer and o-ring. The leak jet shouldn't effect starting, just how much fuel gets sprayed into the cylinder when you pump the throttle. My bike tells me where to put the pilot by how it starts cold and hot. If it's a bit rich it will fire right up cold, with the choke, but be hard to start hot, with hot start. If it takes more than a kick or two hot it needs leaned out a bit. If it takes more than kick or two cold it's a bit rich. It usually doesn't need more than a quarter to half turn to dial it in.
That being said you still need good hot spark.
Or you could just pull it behind the quad? ;)
That being said you still need good hot spark.
Or you could just pull it behind the quad? ;)
Come on dead kill switch! Passed the coil, them electric parts new get pricey, and buying used can get real iffy? Or, it could be a bad/loose connection, there are not that many electrical connectors? A wire laid wrong and rubbed/melted through? Vintage Bob
Plug cap, lead wire, then the coil, and the 8 dollar kill switch, cheap. CDI box, stator, expensive. And, the pick up on the side of the rotor, can get whacked out of adjustment, or worse, all corroded up. Keep at it. Vintage Bob
When you pulled the left side engine cover, did you inspect that stator? most likely not.
When you have problems on the bottom ends of the CRFs, the wire leads are soldered to the stator. Basically the metal particles will stick between the leads shorting out the pickup. Simple fix to clean it off.
When you have problems on the bottom ends of the CRFs, the wire leads are soldered to the stator. Basically the metal particles will stick between the leads shorting out the pickup. Simple fix to clean it off.
Yeah, Bob, this ain't yer 'ol two smoker. :nener: As far as I know there's no adjustment on the pick up. It's also oil bathed so corrosion shouldn't be the problem. Particles could end up getting stuck to the terminals I guess. Hopefully not because that means you've got much bigger fish to fry. Go pick up a gasket and pull the cover. It's pretty simple and will allow you to look for any shavings in the ignition or sump screen as well as giving you an opportunity to check for bearing play. I just bought a side cover gasket and I think it was around 10 bucks.whenfoxforks-ruled said:
