Best way to test 0 clearance valves?

i would never sweat clearances so bad that i'd try grinding down shims the shims are so hard its almost impossible to start with but even if you could cut them can you get them square enough that they wont break or spit out of the bucket or the retainer. be carefull not worth doing in my books motorjobs arent cheap boys. and as larry has said .001" here and there with valve cleartances isn't anything to lose sleep over.

Excerpt from FSM



Good Fortune!

This is a paragraph from a valve shim manufacturer:

"Our tappet shims are made from the highest quality EN24 chromoly steel. The
shims can be ground to any size, from 5mm down to a minimum of 1.5mm. We
sell both blanks and pre ground shims. The blanks allow the client to grind his (or
her!) own shims for total control, or we can pre grind the shims in increments of
.025 (1/1000") removing the need for client machining facilities."

I think that "grinding" referred to in the FSM would be someone with a bench grinder or other hand grinder that would cause shim fracture from the vibration. The latest technology has incorporated different micro finishes that can cut friction dramatically, read free horsepower and less oil temp.

Patton wrote:

If dealing with over-bucket shims, meaning visible shims atop buckets where cam rides on the shim, such as large Kaw fours ---

On those with ZERO clearance:
With cam lobe pointing away from bucket, see whether the shim will turn (indicates minimal clearance), or whether it won't turn, being too tightly held by the cam base (indicates no clearance).

If shim will turn, would replace existing shim with next size thinner shim.

If shim won't turn, would replace existing shim with shim two sizes thinner.

I was just thinking, (ok, you all can come out from under there lol) is it possible to measure the amount of "release" at the bucket with a dial indicator when you take the cam caps loose and remove the cam to see how tight the shim is? If so you could subtract that from the the shim thickness to find zero clearance and figure out what size shim you do need.

Motor Head wrote:

This is a paragraph from a valve shim manufacturer:

"Our tappet shims are made from the highest quality EN24 chromoly steel. The
shims can be ground to any size, from 5mm down to a minimum of 1.5mm. We
sell both blanks and pre ground shims. The blanks allow the client to grind his (or
her!) own shims for total control, or we can pre grind the shims in increments of
.025 (1/1000") removing the need for client machining facilities."

I think that "grinding" referred to in the FSM would be someone with a bench grinder or other hand grinder that would cause shim fracture from the vibration. The latest technology has incorporated different micro finishes that can cut friction dramatically, read free horsepower and less oil temp.

who are they making shims for and who made the origional kaw shims?

Sorry I've got NO idea who would have made the OEM Kawasaki shims. Most of the aftermarket seems to be K&L supply.
Here is the Link to these people I quoted if interested.
www.arrowprecision.co.uk/Assets/download...0Brochure%202005.pdf
As far as I know all of the shims would have to be ground to start with, then its what they do for the final process that makes them different. Coatings, and different micro patterns. This is why newer shims have the potential of being better than OEM.

I thought Kaw oem shims had some sort of surface hardening that would resist grinding and be removed or damaged if ground.

Even vaguely recall reading horror stories where shim failure occurred supposedly due to grinding, and caused significant damage.

But have zero personal knowledge about this, although it seemed to make sense.

Not taking any position on the matter, just choosing to play it safe.

Good Fortune!