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800screws

can someone scan the shim chart for a 426

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I am pretty sure one shim size is .001 of an inch. Valve clearance seems to be easier to me if I use thousandth's instead of metric measurement's.

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I am pretty sure one shim size is .001 of an inch.
It's not. .05mm is very close to .002", however.

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It's not. .05mm is very close to .002", however.

Correct, but one shim size is .001 inch as all the shims I have used are broken in size by more than .05mm. In other word's they go from a

#242 to #245 then to #248. This is where using the metric measurement is kind of a pain as a #245 shim is 2.45mm thick but then the next smaller is a #242 and the next larger is # 248. If you use thousandth's then you know if you are .002 inch tight or loose go up or down 2 shim numbers.

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Correct, but one shim size is .001 inch as all the shims I have used are broken in size by more than .05mm. In other word's they go from a

#242 to #245 then to #248.

First, Yamaha and the popular Hot Cams shims are sold only in increments of .05 mm (175, 180, 185, etc.) Honda sells theirs in .025 mm steps, and label them in round numbers like 170, 172, 175, 178, and 180. They do interchange with Yamaha, and the Yamaha factory uses shims in increments of .01mm to build their engines.

Second, the shim sizes you mention would suggest that you are not working on a YZF unless it has some very non-standard parts in it. The sizes are well outside the normal range.

Using metric measure is no more complicated than English. Most feelers have the metric equivalent marked on them. They don't match perfectly, but the largest error I know of offhand is in measuring .22mm for a YZ250F exhaust. For that, I use a .009" gauge, which is too large by .0086 mm, a whopping .00034". If you're going to try to tell me that you can detect that difference with a feeler gauge, I'm going to have to laugh.

Use the metric markings rounded off (i.e., .006" = .1524 mm = .15 mm) and selecting the shim sizes requires no mental conversion at all.

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First, Yamaha and the popular Hot Cams shims are sold only in increments of .05 mm (175, 180, 185, etc.) Honda sells theirs in .025 mm steps, and label them in round numbers like 170, 172, 175, 178, and 180. They do interchange with Yamaha, and the Yamaha factory uses shims in increments of .01mm to build their engines.

Second, the shim sizes you mention would suggest that you are not working on a YZF unless it has some very non-standard parts in it. The sizes are well outside the normal range.

Using metric measure is no more complicated than English. Most feelers have the metric equivalent marked on them. They don't match perfectly, but the largest error I know of offhand is in measuring .22mm for a YZ250F exhaust. For that, I use a .009" gauge, which is too large by .0086 mm, a whopping .00034". If you're going to try to tell me that you can detect that difference with a feeler gauge, I'm going to have to laugh.

Use the metric markings rounded off (i.e., .006" = .1524 mm = .15 mm) and selecting the shim sizes requires no mental conversion at all.

Grayracer, no need to be so angry, I never said that the English measuremant was more accurate than the metric or that I could feel the difference on the feeler guage. 800screws was asking for a shim chart so I was simply trying to let him know a way to get the shim size without one. The fact you use a .009" guage to measure a YZ250F valve is the reason why I gave the info to start with, it seems a little easier to deal with. If the YZ-426 uses the smaller 7.5mm O.D. shims and they are not available in the .025mm {.001"} increments then I appologize for the bad information. The last bike I shimmed used the 9.5mm O.D. shims and they are available in the sizes I mentioned. It has been a while since I checked our YZ-250F which uses the smaller O.D. shim. Since Satch0922 posted the chart I guess it does not matter, 800screws has the info he needs.

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