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I have a 04 CRF250x that the right intake valve went to zero and I am having

my seats cut and new SS valves and spring kit. I will also do piston and rings

at the same time. I was also told it is a good time to do the cam chain.

I am looking for the best sequence procedure to follow. I would assume after new piston is installed you would install the head,get the piston to TDC,pull

the flywheel and install the cam chain. I'm sure I am missing some things and any tips would be greatly appreciated!

Thanks!!

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if you are going to replace the cam chain the easiest time is when you have it torn down to the cases because you might have to remove the slider from the cases after you pull the flywheel. it should be faily simple then

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I don't know if it's too late, but I just did the same thing with my 05 and it lasted a whole 25 hours. I learned the hard way that I should have called Ron Hamp. Brad.

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When you tear down the motor, pull the left side cover, the flywheel, the little retainer tab and remove the cam chain. Install the new cam chain and then the rest of the top end. I pull the cam chain up with a wire and then drop the cylinder and head down pulling the wire and chain through. I hook the wire to the handle bars to keep the chain up. Might as well leave the flywheel and side cover off until you get the cylinder and head back on. Then set the timing and finish assembly. I replaced my cam chain at 150 hours, I think they last along time.

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Thanks,

Dances...... is there anything I need to worry about when setting the timing?

At the time of tear down I had the piston at TDC and lined up with the timing marks

on the right side inspection hole. When I looked at the left side inspection hole the

timing marks were off slightly??

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The main thing is that your piston is at TDC. I never relied on the marks in the right side inspection hole. Piston TDC then line the hash marks up with the head with the cam lobes facing rearwards and you should be good to go. Turn it over slowly by hand just to make sure.

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The main thing is that your piston is at TDC. I never relied on the marks in the right side inspection hole. Piston TDC then line the hash marks up with the head with the cam lobes facing rearwards and you should be good to go. Turn it over slowly by hand just to make sure.

Thanks,

How's that new XCFW? I'm thinking of going the same way.

Thanks again for the help!!

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Thanks,

How's that new XCFW? I'm thinking of going the same way.

Thanks again for the help!!

The new xcf-w is incredibly fast, light and very well suspended. Needs nothing but guards, and maybe a sparky. Super easy to work on too.

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