Need help with valve adjusment

tclayton9 said:

I need help calulating the shim size on my 99 zx6r. The question is if I measure my clerance with a feeler gauge and i get a clerance of 0.15 for example, but the required clerance is 0.23, and the current shim size is 2.75. Do I compute the new shim size like this: 0.23-0.15=0.08 which leads to 2.75-0.08 which gives me a new shim size of 2.67? I seen this online and I just wanted to verify.

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Correct. Need more clearance=install smaller shim. Need less clearance=install bigger shim. Generally shims only come in increments of .05mm, so I would install a 2.65mm shim if that is near the middle of the specified range. Honda OEM shims come in .025mm increments if you want to be more precise.

Check out the attached spreadsheet for calculating shim sizes.

Well i ran into a problem. I used my smallest feeler gauge size (0.10) and it still will not go between the cam and bucket. I have the cams 180 degrees so that the lobes are not hindering the gauge but it still isnt working.

Just had a problem like this lol...http://zx6r.com/mechanical-technical/63716-where-did-my-math-go-wrong-valve-adjustment.html

damn lol but no blade on my feeler gauge will go between the bucket and cam

Subtract the maximum allowable clearance from whatever shim is in that location and use that. I should get you in or near the correct range. (assuming your measuring correctly and actually have 0.00 lash)

How long has it been since the last time the valves were adjusted?

The bike has 22k on it. i bought it in November with 18k. This is not my first time performing a valve adjustment. Ive done on bikes/atvs, but its the first time I ran into this problem

well I tried again just a few minutes ago a few of my clearances are 0.08 and 0.10 and a few are just plain zero.

Did you happen to do a compression and leak down test?

No I didn't. It was running fine before I started the adjustment.

It's just hard to imagine after only 22k you'd have 0 gap and a compression/leakdown test would tell you how well the valves are sealing (among other things). How many valves have 0 gap, just 1? What's the measurements on all the others, more normal? You just have to put a smaller shim in and remeasure but something seems odd for sure, like maybe you're not getting the gauge in the right place. Do you have the bent feeler gauges or did you bend some straight ones? I just bend the straight ones to the shape I need personally.

I haven't checked all of them yet due to the fact it scared the shit out of me when the feeler gauge didn't clear the bucket and lobe. I have the feeler gauge that's 4 inch long L shaped perfect for tight spaces. I know I'm measuring right because I tried every way possible to see if I could get the gauge between the lobe and bucket. If I purchased the bike and the bike never had a valve adjustment I could believe what's happening.

Well somebody screwed something up. I can tell someone attempted to do a valve adjustment, but they didn't know what they were doing. all of my exhaust valves have .008/.203 except for 1 on cylinder #2 which was .010/.254. All of my intakes are at 0.