1st timer valve adjust??? 2000 yz 426

Ok---The shops are all backed up @ 3 weeks so I am going to adjust my valves myself. :banghead: ---I also remember seeing a post about a counter balance shaft? keyway? or something that comes loose and makes a "rattle" sound? Valves have never been checked or adjusted, 1 1/2 seasons of hard supermoto riding and she's hard to start. I have been told my valves have likely tightened up. My local Yamaha shop has no service manual in stock and does not have a shim kit but will sell me the shims I need.(if they are tight wont I remove some?)--Any links or info to help is very appreciated...... :banghead:

You're going to want to have a manual, unless there are some detailed sites out there that someone can recommend.

I have the 03 manual in softcopy, (PDF) which should work fine, but it's large, even compressed.

I wonder if I can pull some pages out and send them to you?

This article is for a 250F, but it's a good one, and other than the fact that the exhaust valve clearance is different, the procedure is the same. Your specs for the '00. which has stainless valves, is .10-.15mm for the intakes, and .25-.30mm for the exhaust. You will also not have to trim a feeler gauge to get it onto the center intake.

http://www.thumperfaq.com/valves.htm

There is an 01 manual in PDF on motoman393.thumpertalk.com- use that as a guide, but use the clearance values grayracer posted. Don't worry, it's not as bad as it seems.

Thank You to all that helped with the info, I will attempt this in the next day or so. Still one question, do I need to check the counter-balance retainer nut?or keyway because I remember something of these comming loose?

Thank You to all that helped with the info, I will attempt this in the next day or so. Still one question, do I need to check the counter-balance retainer nut?or keyway because I remember something of these comming loose?

The counterbalancer nut came loose on my '00 426 and the key started slopping around causing a "clackity-clack" noise. I had to replace this .98 cent part twice (about 5 hours each time). If you haven't had any problems (you'd know it from the noise) then yours is probably one of the bikes where this issue won't surface.

If you still want to check it, you can remove the clutch cover and put your hand through (toward the front) and see if you can move the nut on the crankshaft back and forth with your finger (on mine, I could). This nut has a lockwasher that bends over the nut flat, but it still can come loose enough to rotate slightly.

If you need to tighten it or inspected it more closely, the entire right side cover must come off.

I wouldn't worry too much about the CB key unless your motor is really noisy. Remember that these bikes have a lot of moving parts inside and create a fair amount of valve train noise even when everything is top notch. Check the valves first and go from there.

Thanks to all that helped with the input!!!!!!

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