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07 rmz 250 "kickin my butt"

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I bought a o7 rmz 250 for a woods bike I have an o8 MX bike that i love and havent had a single problem with but the o7 is another story. I bought it got it home and rode it a while on the trails stalled it and like to never got it to start It was like trying to kick a hot 450 I weigh 180 and i was jumpin up and not being able to kick it over on the compression stroke. I got i home it cooled off and started fine. I rode it till it got hot again and then the same thing. I well maybe the compression release was not working so i got into the head and it was working fine. I pulled the head off and there was alot of carbon build up on the exhaust vavles and in the exhaust ports. I depressed the valves and noticed that there was carbon flaking off very close to the valve seats. which would explain why i have noticed a pop like a backfire in the exhaust sometimes when i am trying to kick it. it exhaust valve is not seating. also I noticed that the head pipe had a pretty good dent in it close to the head which would explain the bad carbon build up. I cleaned all the carbon off. same problem. Has anyone had problems with the kick start shaft and gear? could it be a bent valve? I am not making any progress anymore and need some input from another source. what am I over looking? the bike runs great when its running just dont kill it.......HELP

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ok guys I figured out what happened. I talked to the guy that owned the bike before me we were talking about the bike how it ran when he had it and any problems he had during that time. I asked him about how he serviced the bike and he told me that he changed the oil and cleaned his filter after every ride which is good. and he said he followed the oem intervals for changeing the top end and everything. general seemed like he took good care of the bike while i was there talking to him he had another o7 rmz 250 he was serviceing and basicly was doing it the whole time i was there. He filled the bike with oil and proceeded to check the level by removing the check screw all while the bike was still on his center stand. It did hit me right away but just a few seconds later i realized that he had checked the oil level while on the center stand which is not correct. i asked him how does know when the level is right and said I let is run out till it kinda slows down and then put the check screw back in. I told him that the proper way to check the oil with the check screw is with the bike off the stand and upright. and explained how the center stand tilts the motor and would not give him a good measurement. so he took the bike off the stand and sure enough is was about 75 to 100 cc's low. He thankd me and I went on home. I thought about how he changed the oil later and thought If he consistantly ran his bike a little low on oil the whole time he had the bike there could be some damage i am not looking for there. sure enough I put the cams back in the head torque the caps to spec and on the exhaust side there was about .0020 of play between the cam and the cap. so now i gonna spend about 550 dollars to get a new head and cams.

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the 07 and 08 rmz 250's take exactly 1 qt of oil and it doesnt hurt to put just a few cc's more. That check bolt is useless, forget it is there. Change ur oil every 3-4 hours and you will be just fine.

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I don't have my manual in front of me, but .002 does not sound excessive.

What were the valve clearances? How do you know the exhaust valves were leaking? Did you pull the head and fill the exhuast port with solvent and see it leaking out of the valve seats?

What jetting are you running?

I had a little trouble following you post, so pardon me if I am way off base.

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I agree with above, dont bother with check bolt. make sure to get all the oil out when changing and pour in one qt+ a few cc. Check your fuel screw setting, I believe it should be approx 2-1/4 turns out. Check pilot jet make sure previous owner didnt lean out pilot circuit. Also, when starting these bikes you dont have to kick on compression stroke like early model bikes. Quick, smooth continous kicks, NO need to jump up and down. squeeze hot start lever and kick same time with slight blip or no throttle.

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thanks for the info. I did say it was .002 out but thats was a guess on my part i didnt put the dial indicator to it. It was enough lash in it to wear the cap and cam. and had evidence of binding. Which I think would explain why it was so hard to kick over at times.

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I have heard of the cams/caps seizing like you described.

There might be some companies that can repair it?

Good luck getting her back together.

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