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2005 kx 250f - help if possible

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Sorry to post this in here but I can't get help from the bikes actual thread.

I had a recent issue with the bike, no compression, would start when pulled behind the four wheeler but not kick start. Took the head off and the valves were pretty much gone. I ordered new ones and new piston rings just in case.

Now after reassemble the bike feels like it has great compression, wouldn't kick start still but has a lot more power when we pulled it off. Didn't ride but a minute to not harm anything else. Now as far as shims go, I did not change. We did check them and both sets of valves are taking a feeler gauge at least 3 sizes higher than suppose to so I know the valves are to loose meaning I need to order a shim kit and go with bigger shims. Now is this why my bike still wont kick start? Its so tough to kick and is this because when the lobes are turning the valves are probably barely opening causing to much trapped air? Just want to make sure Im headed in the correct path. Thanks guys.

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you need to have the seats cut to match the new valves or you will run through a set of valves in 15 hours or less, and you will continually have to shim them. buy a hot cams shim kit off of ebay or rocky mountain mc or bike bandit, you will use them, it is a much better investment than getting them 1 at a time from a dealer, not to mention the hassle involved. that is why the bike wont kick start, valves off just .002 will cause the bike not to kick start....

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Yes the old shims are no good. You need to check your clearances and put in the correct shim. That is why it isnt starting

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I got the head checked and the mechanic that did, said the valves seated great in the head so I didn't get the head worked on. He inspected it and put them in. I have ordered the hot cam kit and it will be here next week. I know there is some type of formula to use for finding the right shim, use it or just trial and error?

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i have been looking for a shim size calculator, thats good stuff. now if i can only start using the the mm numbers instead of the SAE numbers this will be very helpful, thanks Coviello, that beats using the metric numbers on the feeler gauge and doing the math...

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hopefully your mechanic didnt "eyeball" the seats (as i did) and simply clean the funk off with solvent and put it back together, they need to be spec'd out to the proper angles/profiles. i though mine "looked good" but 16.7 hours later i was buying a new set of kibblewhite intakes (not to mention shimming at 6.5 hrs, 11 hours, 14.1 hrs, and then finally deciding i needed to get the work done). just make sure he didnt use the "looks good, i dont have to measure them" method i did...

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Nice calculator! The seats I am not sure of, if he eyeballed them I wouldn't know. I will know when I get the shims in and ride I guess lol. If it happens then I will get in done right next time. I am new to this so just trying to get the bike actually kicking and all.

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Sorry to jump in on this topic, but i am working on the same bike and i have .13mm clearance on one of my intake valves and smaller than .04mm on the other. My feeler gauge only goes to .04mm and it won't fit. What could be the issue here? Maybe a destroyed valve? The bike will run OK if i tow it to start, just as komakazic15 said his does, just not to kick it.

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Sorry to jump in on this topic, but i am working on the same bike and i have .13mm clearance on one of my intake valves and smaller than .04mm on the other. My feeler gauge only goes to .04mm and it won't fit. What could be the issue here? Maybe a destroyed valve? The bike will run OK if i tow it to start, just as komakazic15 said his does, just not to kick it.

If your smallest feeler guage wont fit the put "0" into the calculator for your valve clearance. Valve isnt destroyed it just needs to be shimmed

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This may sound really dumb but I have no clue. The gauges changed over to mm. How do I know the mm size? Is .004 = to 1mm

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The clearance on the intake valves should be between 0.10 - 0.15 mm.

You should have no problem measuring the clearance if you have metric feeler gauges.

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Got the shims in today and after a long day on it, it cranks. Running pretty fine except I know the carb needs adjusted. I am having one problem it seems as if oil is coming from the crank case overflow tube. I'm not sure why and also the oil is milky looking, almost like water or coolant is in it. What could be causing this leaking? Sometimes its not so bad and others it is. Im not riding until fixed but so far its ok besides that. It also seems like behind the front sprocket there is oil coming out. Last but not least the front oil plug on the head came out, I found it and assume that it just came out from the bolt being loose so I put it back in and tightened it back down. Is that just a cap or am I missing more to the plug. Someone please just text me or write on here 334-520-9460

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