Newbie valve check questions

I am going to attempt to do my valve check here in a week or so. I have to pull the motor right?

Also, the shims...are those sold in kits? Or are they something I figure out what size I need then run down to the dealer and pick some up?

And, where is a good place to get a measuring tool?


No, you don't need to pull the motor, just the valve cover. Follow the directions in the manual, it's very thorough and easy to follow. Read it a couple of times before you even put your hands on your tools. If you have any questions after reading it, post them and someone will help you out. It's an intimidating process the first time, but it's really not hard at all.

Tool-wise, you'll need some angled feeler gauges, I found the Motion Pro set works well. Also, get a 1/4" quality torque wrench with inch-pounds on it, it's a must have. As far as shims go, before you pull the thing apart, call your local dealer or independent shops and find out if they have shims in stock. You'll probably need shims in the 170-185 range, as they come in increments of 5. For some reason, a lot of dealers do not stock them, but they may let you trade your old ones in. Once of my local independent parts stores had them to sell, but they ain't cheap, about $10 per shim if you can believe that. Lastly, make sure have some assembly lube when you put it back together.

Here are some great sites to look at with pictures of the process and good tips:


MotoMan 393

Have fun :) ..SC

RIGHT ON! Thanks for the tips and links. :):)

So is there any specific kind of feeler guage I need, or can I just go down to shucks and pick one up??

I photocopy the manual pages beforehand so I have a disposable copy to work from in the shop. Map all the clearances, as you may be able th shuffle your shims around and only get 1 or 2 new ones. :)

Motion Pro makes a set of 3 gauges with 2 blades on each. They're angled so they can get in the tight spaces easier. You should be able to pick them up at any reputable bike shop...SC

In response to KiltLifter, even better than photocopying the manual, print from the PDF manual. I got a PDF copy of the manual. You can download one from the following site. Note sure if they have all the manuals on this site, but I know they have the 03WR450 manual available:

At the moment, the server seems down for this site, but this morning I was browsing it for other manuals.

clark4131, I agree, the Motion Pro are great!! Makes live much easier; however, they don't make them thick enough for the exhaust side. The Motion Pro go up to .008" and the exhaust spec goes to .010". What do you use on the exhaust side? I have a set of feeler gauges (12") long. I"m thinking of cutting the .008 to .012 blades to the same size/shape as the Motion Pro and making a little hangle for them and rivet the blades to the handle so it is similar to the Motion Pro. That is, unless you found other feeler gauges off the shelf that work great.

I have had issues with feeler guages.

1. You need metric feeler guages

2. You need a thin profile to check the middle input valve. I grinded down the width of my feeler guages

3. Most feeler guages go from .15 to .20, so measuring inbetween, like .17 requires you put two feeler guages together, ie. a .10 plus a .17.

4. I ordered the Hot Cams kit, 9.48 OD, catalog numbers HCSHIM08 and HCSHIM09, they are $35 each. Valves are usually tight, so, you probably only need the 175 and under kit - HCSHIM08. I ordered both because I have two Yamahas and plan to keep them and shipping was a little high at $10. The dealer charges $10 a shim and you have to wait, so, I figure that is highway robbery and I would rather have a bunch of extras and give my money to Hot Cams. For the Hot Cams refill kit above, you are paying $1 and change for each shim, so, these guys are fair.

5. I measured one bike so far, the YZ250 (so, I can decide if I needed to order the kit or not) I will do the WR426 when I get the kit. On the YZ, I found one tight exhaust valve, just barely under spec, the other one was borderline. All intake valves were inspec. on the YZ, but, on the lower end of the range, ie. tighter, not looser, so, it seems I will be putting in thinner shims as the bikes get older, ie. the HCSHIM08 refill kit.

PS. Hot Cams also has a generic 9.48 OD shim kit - HCSHIM02 , but, it has sizes that you would never use on a WR or YZ, so, I went with the 2 refill kits instead. This is cheaper and gives you more shims in the sizes that you would need for our bikes. :)

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