What valve shims do i need if i know my clearences

Ok so i have my clearances written down. How do i figure out what shim i need? Im sure its a simple math equation but i don't want to guess and get the wrong ones. For example my desired clearance is .005 or .127. My current clearance is .008 or .203. What shim do i need to get the desired clearance? Other examples .004 or .102 and .007 or .178. What shim would i need for these? Thanks

First off what model? You need to take out each shim and read the bottom and record it along with your clearances.

In the factory service manual for whatever model you have is a chart that lists shim sizes and valve clearances and shows what shim to use.

Later, Doug

Including information about bike year and model is helpful to viewers and usually elicits better responses.

It's easy to put the information in your signature where it shows in all posted messages, past and future.

And the signature may be changed whenever and as often as desired.

If wanting a signature showing information about the bike in posted messages, it's easy to do.

Here's how:





Good Fortune!

Just look at the shim table in the Kawasaki Service Manual. No calculations or guesswork required. Ed

You need to know what shims you already have to start with though,as things wear clearances change.

Waynecarpenter wrote: Ok so i have my clearances written down. How do i figure out what shim i need? Im sure its a simple math equation but i don't want to guess and get the wrong ones. For example my desired clearance is .005 or .127. My current clearance is .008 or .203. What shim do i need to get the desired clearance? Other examples .004 or .102 and .007 or .178. What shim would i need for these? Thanks

Each shim increment of .05 = .0019" of dimensional change [05 * .03937] Keeping in mind that you might not have an exact .008" of lash, here's how shim numbers work out.

Example - Current shim = 2.50 - Current lash = .008" [your first example]
Change to 2.55 shim [1 size or .05mm] = .0019" reduction in lash. [thicker shim]
.008 - .0019 = .0078"new lash [a tight .008]
Change to .260 shim [2 sizes or .10mm] = .0038"
.008 - .0038 = .0042" new lash [a loose .004]

So, as you can see, you're targeting a range rather than a specific lash number. Sometimes you hit your "ideal" target, sometimes not. When not you have to decide between a little loose vs perhaps a little tight. On exhaust valves....it's smart to go with the "little loose" choice.

Generally, don't use a shim that ever puts you "a little tighter" than low rage spec on any valve.

Also, where you check the lash is important. Theoretically, anywhere on the base circle should yield the same measurement. In the real world, it often doesn't pan out. So if you're checking using the sprocket marks then stick with that. If you're checking using the lobe away method [which is the best way IMO] then stick with that.

Waynecarpenter wrote: Ok so i have my clearances written down. How do i figure out what shim i need? Im sure its a simple math equation but i don't want to guess and get the wrong ones. For example my desired clearance is .005 or .127. My current clearance is .008 or .203. What shim do i need to get the desired clearance? Other examples .004 or .102 and .007 or .178. What shim would i need for these? Thanks

I think you mean 0.05, 0.08 & 0.04 mm, but the inches don't equate. Apparently, the calculations were done by dividing by 0.0394 instead of multiplying.

To convert metric to Inches, either multiply the metric number by 0.0394 or divide by 25.4:

0.05 x 0.0394 = 0.00197"
0.05 / 25.4 = 0.00197"

Keeping everything metric is simpler.

martin_csr wrote: .........................Keeping everything metric is simpler.

+1 ! And if you don't already have one, buying one of these will help too. No inch/metric conversion necessary. Ed

650ed wrote:

martin_csr wrote: .........................Keeping everything metric is simpler.

+1 ! And if you don't already have one, buying one of these will help too. No inch/metric conversion necessary. Ed

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Get a set of feelers that shows both mm and inch values and goes down to .00015" and snag a set of digital calipers. Probably pick up both at Harbor Freight or Sears pretty cheap.

Pick up the phone and order a set of performance cams....tell them you want xxx metric base circle size....then listen to the silence, followed by WTF are you talking about :woohoo:

I've got a Snapon I think set label'd both and each blade is two size's.
First 3/8" is the small size they run like this 004 and 006 next one
005 and 007 and so on.
Work's great for a go/no go gauge.

sorry been real busy lately. just getting to this. i always put my bike year and model haha. must have slipped my mind. Its a 1982 z750 e. i have a set of feeler gauges. this is how i found my current clearances. it has booth measurements on it. ill still to metric from now on. i measured using the lube way. also i have a manual and i have looked for the info but unless I'm missing it overtime its not in my manual. ill go ahead and check to see what shims i currently have and return with the info. thanks everyone.