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Checking Valves on CRF450 how to with pictures

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Is there anything out there that covers checking valves and the step by step process with a list of required tools?Anything with pictures and specific to the CRF would be great. I have never worked on a four stroke but am somewhat familiar with 2 strokes. It sounds like checking the valves isn't too difficult but I would feel more comfortable if there was a reference guide with pictures.

Thanks in Advance

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Is there anything out there that covers checking valves and the step by step process with a list of required tools?Anything with pictures and specific to the CRF would be great. I have never worked on a four stroke but am somewhat familiar with 2 strokes. It sounds like checking the valves isn't too difficult but I would feel more comfortable if there was a reference guide with pictures.

Thanks in Advance

I'm pretty sure it's covered in the Owners Manual (it's definitely in the Service Manual). It's really simple (and I'm no mechanic), just pull the seat/tank off, then remove the valve cover, rotate the crank to TDC and use a feeler guage to check the clearances.

You'll need:

8 & 10mm sockets or T-handles for the seat, tank and valve cover bolts

10mm allen head (for the crank sight hole cap)

8mm allen head (to turn the crank)

feeler guage

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if youre in so cal..bring the bike by my house with the seat and tank off and I will show you how to do it.

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thanks Kritter. Unfortunately, I am in Seattle. I really appreciate all the info in a quick time.

Thanks again fellas!

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By the way, when I check and adjust my valves, I didn't have to adjust the cam chain adjuster. I don't know if it's wrong but this is what I did to remove and install the cam chain without fiddling with the cam chain adjuster:

- slowly unscrew the bolt that holds the cams in place.

- i then slowly tilt the cam up so that I can remove the cam chain.

- that's it. then I just use a zip tie to hook it to some place on the bike until it's time to install it again...

I find that I did not have to make that cam chain tool thing. I don't even have to touch it.

Is this wrong? If it is, I was still able to adjust the valves. :cry:

There's a post with pics in the CRF250 forum on how to check valves.

It's at the top of the page.

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By the way, when I check and adjust my valves, I didn't have to adjust the cam chain adjuster. I don't know if it's wrong but this is what I did to remove and install the cam chain without fiddling with the cam chain adjuster:

- slowly unscrew the bolt that holds the cams in place.

- i then slowly tilt the cam up so that I can remove the cam chain.

- that's it. then I just use a zip tie to hook it to some place on the bike until it's time to install it again...

I find that I did not have to make that cam chain tool thing. I don't even have to touch it.

Is this wrong? If it is, I was still able to adjust the valves. :cry:

How did you get the sprocket back on the cam w/o releasing the tension?

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It was very easy. Tilt the cam so that the chain is on the sprocket. Then I use a little pressure to push it down enough so that I can install those 4 bolts. From there, by tightening the bolts, everything went in place.

I was very surprised it worked.

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I ask the same question as TJ above. The cam chain tensioner is a spring loaded device. As soon as the tension is taken off the chain (ie. chain removed from cam sprocket, theoretically, the cam chain tensioner should "top out" or extend all the way towards the front of the bike. Again, theoretically, if you re-install the cam chain on the sprocket and "force" it back together, you're possibly putting too much tension on the chain due to the cam chain tensioner not retracting by itself. Hmmmmmmm..... Mechaincally speaking, you should remove the tension from the cam chian before you remove the chain from the cam sprocket. Hope this helps :cry:

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