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I have no idea what is wrong with this thing!!!

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OK, so I look in the local paper and see an '05 CRF250R for an UNBELIEVABLE amount that "needs work". I go to check it out and the guy proceeds to tell me that his "buddy adjusted the valves and ever since then, it won't start". I bought it, took it home, and tried to start it for over an hour!! I started with the first thing, checking fire- which is strong. It's getting fuel, air filter is clean....

So I proceed to take the valve cover off to check the valves and timing. Come to find out, the timing is 2 teeth off!!! (What a mechanic huh???) I got the cam straight and proceeded to check the valves. All was within spec so I put it back together. Kicked it for over an hour again and gave up. My buddy came over today and pulled me with his quad. Fired up after about 100 yards in 3rd or 4th gear on the asphalt and ran it for about 10 minutes. Shut it down and tried to kick it over.....nothing. Doesn't even try to start. While it was running it was kinda loud. Sounded like a knock coming from the water pump- not sure if that's just how these motors sound though. It definetely ran very well. Instant throttle response and very strong all the way through the powerband.

I call my buddy tonight and descibe the problem. He thinks it's a bent or worn valve, due to the previous owner's improper cam installation. He advises me to take the head off and pour Varsol into it to see if the seats leak....NOTHING!!! No leaks anywhere. I let it sit in the head for 5 mins- staring at the valves and didn't see any signs of leakage- anywhere!!!

Am I totally in left field with this thiing??? What would you guys recommend I try next?

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take the head off and check for proper seal

Proper seal as in the head gasket leaking? I did take the head off to check the valve seats and everything seems to be fine.

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I would pull the carb and give it a good cleaning and put fresh gas in it if you have not done that (Might be gummed up enough to mess up the mix). Not sure what the problem is but I bet the carb has not been clean by the old owner and I bet it sat a around a lot.

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I would pull the carb and give it a good cleaning and put fresh gas in it if you have not done that (Might be gummed up enough to mess up the mix). Not sure what the problem is but I bet the carb has not been clean by the old owner and I bet it sat a around a lot.

Forgot to mention that I already put fresh gas in it, but I didn't clean the carb. I'll try that today. Bad thing is now I have to wait until tomorrow to get a new head gasket. :thumbsup:

Could it be anything else while I have the head off?

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first thing start with checking motor compression with good guage...

100psi will be needed just to start. but starthard. . should be much higher..

then if compresstion is low are you will need to do a leak down test..

are you with me.. min. leak down is 8% for good motor. If leak down is higher

you will need to listen whare air is leaking from, this will tell you whare the problem is..

Need to listen for air leaking around, exhaust "exhaust valve", intake "intake valve" crankcase vent or oil fill hole crank fill not trans fill.. this would be ring issue.. are you with me... thats is where you need to start... have fun. :thumbsup:

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Got the book with the bike.....but I guess since I have only a basic knowledge of motors, I really need to take this to my local mechanic buddy. He's a factory sponsored Kawasaki drag bike guy and he's got all of the necessary tools. Hopefully he can figure it out.

Thanks for the input guys. I really appreciate it!!!

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you didnt mention engine oil, some bike (usually yamahas) will have way to much engine oil in the motor. This doesnt allow for enough room under the piston to allow the crankcase pressures to be absorbed causing hard starting or no starting, it can also can piston pin damage if ran that way.

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Wow. Didn't think of that one. I'm gonna get a head gasket tomorrow, put it back together and ensure the oil levels are correct. Hopefully this is all it is!!!

Thanks!!

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double check your cam timing,

does it have compression when you kick it over fast?, were the valves tight when you got it? it could have a bent valve if it doesnt have any compression., clean the carb and try again

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double check your cam timing,

does it have compression when you kick it over fast?, were the valves tight when you got it? it could have a bent valve if it doesnt have any compression., clean the carb and try again

I checked the timing many times before disassembling. It had very good compression from what I could tell. The only compression tester I have wouldn't work.

If there was a bent valve, wouldn't Varsol leak when poured into the head?

Gonna put it back together tomorrow (provided my local dealer has the gaskets) and thouroughly clean and inspect the carb along with making sure the correct amount of oil is in it.

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Even if it needs a 1000 in motor work to get it fixed then you still got a great deal and like a brand new motor.

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OK, feel better now. :thumbsup:

The guy that had it was "a good 'ol boy" that didn't really know what he had. Got into mud boggin' trucks or something. He kept saying,"This aint no regular 4 stroke or a 2 stroke. It's made different than anything else and it's called a Thumper- all it really means is that it wheelies easier though".

I almost crapped my pants when he said that!!!! Played stupid and talked him down $1500 'cause it didn't run, the clutch lever was bent, the front brakes didn't work, and the exhaust had a big dent in it. It's amazing what cash in hand does to people that need money!!!

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what a deal......seriously if you had the money you can buy an 06 motor with zero hours off ebay for like 2000 then you have a total of 3000 into a bike. Even though you can pick an 04 for that much it would have a lot of hours on it. that is an amazing deal. good luck, hope its somethin cheap then you have the ultimate steal of a bike

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Have you checked the basic electrical components yet? I would also look at the alternator assy. & stator to see if it is not messed up. Damage to the stator will cause your bike not to kickstart.... possibly start by pushing it, or not start at all.

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