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Engine builders: Help please

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This has been an ugly couple of days in my trailer working on my 250x. After a slow installation of a GPR v2.0, I moved on to adjusting the valves (first time ever), following Heckler's excellent plans and the Honda manual.

After numerous times of swapping shims, and remounting the cam and releasing the tensioner, I finally have the clearances where I want them to be (almost, anyway). I put everything back together, double checked all my connections, and no start. It cranks fine, get's an occasional burble, and an occasional detonation in the exhaust which sounds painful. Fortunately, no metal on metal sounds (I did crank it over by hand to make sure I didn't have valve-piston contact).

I'm guessing I lost my mark on the cam sprocket, and have the chain off by one tooth. How do you figure that out? Nothing in the manual talks about it.

I'm about ready to scream!

Any suggestions are appreciated,

thanks all,

Pete

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Did you put a mark on the cam gear and the cam chain link to catch the right link (a line right down the two to line up later). That helped me and I got it the first try without having to jump another tooth. Did it fall off the crankshaft cam gear when you were working on it and skip a tooth. I don't know if it is too tight down there or not for that to happen.

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I'm guessing I lost my mark on the cam sprocket, and have the chain off by one tooth. How do you figure that out? Nothing in the manual talks about it.

I hope I'm answering the question you're asking. In my '04-'05 X Service Manual, it's covered (in very little detail) at the top of page 8-28. When reinstalling the cam chain, make sure the crank is still at TDC (from Heckler). After the cam is installed, the two alignment "hash" marks (from Heckler) on the cam gear should align with the top surface of the cylinder head when viewed from the side. After you're done with all that, the cam lobes (from Heckler) should be pointing toward the rear of the bike. In summation, if the dot on the crank is aligned with the arrow on the case and the "hash" lines on the cam gear line up with the surface of the head and the lobes are pointed toward the rear of the bike, you're at TDC and everything is lined up :cry: .

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Thanks for the responses guys..

A couple of hours to cool down, and a conversation w/ my friend the engine builder has made me feel a bit better. I had the cam in & out several times trying to get all the shims just right (trying to measure consistantly is a bitc%for me). I was very cautious the first couple times about marking and putting zipties on the chain & the sprocket, but was less & less cautious towards the end.

My friend reminded me to bring the piston to TDC using a screwdriver in the spark plug hole, and rock the crank back & forth to exact TDC. Even though he's never done a single, he guessed correctly about hash marks on the sprocket, and how they should line up w/ the valve cover gasket.

I asked "how will I know I'm at the right TDC?" He let me chew on that and reminded me that the crank only has one TDC, it's the cams that determine what stroke it is, duh.

Ok, one more try today, and then it waits for a couple days.. I'll post my results here (if they're good)

Thanks again,

Pete

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I asked "how will I know I'm at the right TDC?" He let me chew on that and reminded me that the crank only has one TDC, it's the cams that determine what stroke it is, duh.

Just trying to save you some effort. As I said above, if the dot on the crank is aligned with the arrow on the case and the "hash" lines on the cam gear line up with the surface of the head and the lobes are pointed toward the rear of the bike, you're at TDC and everything is lined up correctly. No guess-work involved. Good luck!!

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SUCCESS! Thanks for the help... amazing what can be worked out when you can think slowly and rationally. Or at least when your friends can. I was off by a tooth.

Things I've learned looking back on this:

I shouldn't have much bothered to mark the chain and sprocket. As long as all the work is done at TDC w/ the hash marks lined up at the beginning, all I needed to do was put it back that way. I never thought about, or looked at the hash marks that last time I put the cam in, I just tried to get the pen marks to line up.

Having the right feeler guages helps a lot. I'm not sure what type that is, but mine aren't it. When I bent them to fit under the lobes, I created high & low spots which affected my measurements. It takes a while to figure out the exact angle of approach to slide them in, and that angle has to be used EVERY time.

Except when you're learning (and making mistakes) this isn't a bad process. When I wen't back in to fix the cam chain issue, I went from full buttoned up, fixed the cam, and rebuttoned up in 45 minutes.

I learned alot about how my bike works.

Thanks again, guys.

Pete

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SUCCESS! Thanks for the help... amazing what can be worked out when you can think slowly and rationally. Or at least when your friends can. I was off by a tooth.

Things I've learned looking back on this:

I shouldn't have much bothered to mark the chain and sprocket. As long as all the work is done at TDC w/ the hash marks lined up at the beginning, all I needed to do was put it back that way. I never thought about, or looked at the hash marks that last time I put the cam in, I just tried to get the pen marks to line up.

Having the right feeler guages helps a lot. I'm not sure what type that is, but mine aren't it. When I bent them to fit under the lobes, I created high & low spots which affected my measurements. It takes a while to figure out the exact angle of approach to slide them in, and that angle has to be used EVERY time.

Except when you're learning (and making mistakes) this isn't a bad process. When I wen't back in to fix the cam chain issue, I went from full buttoned up, fixed the cam, and rebuttoned up in 45 minutes.

I learned alot about how my bike works.

Thanks again, guys.

Pete

it amazes me how much business we take from dealers and shops by going on this sight. it makes us regular white collar dudes look somewhat mechanical by tearing a bike down and asking questions on how to fix it up. genius place to go, just genius.

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