valves shims CAM PHOTO!

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BTW, the industry only uses 2 shim diameters TIKO, the 9.48 mm being the most common. All 4 japanese, Husqvarna, Aprilia, build bikes that use 9.48 shims, so don't limit your search to Yamaha dealers.
After reading that I thought, "cool, I have some shims at home that might work!" Digging through my bike parts bin revealed some shims left over from many many years ago when I had a 1978 GS750. But no way they are gonna work because they are over an inch in diameter (like 30mm or so)! So I'm guessing the MODERN industry only uses 2 shim diameters. :lol:

 
99.9% of the time the valve clearance will be too small if it is out of tolerance.

I've heard stories of people using fine Wet & Dry sandpaper on a piece of plate glass and sanding their old shims down by a few thousandths.

You'd have to have a micrometer to measure the shim and keep measuring as you polish them down until get the added clearance that you need.

Has anyone here ever done this? I'm sure the shims are hardened. I wonder how tough it would be to gain the clearance to get them back in spec?
I think I'd rather just buy them..............that's too much work :)
 
99.9% of the time the valve clearance will be too small if it is out of tolerance.

I've heard stories of people using fine Wet & Dry sandpaper on a piece of plate glass and sanding their old shims down by a few thousandths.

You'd have to have a micrometer to measure the shim and keep measuring as you polish them down until get the added clearance that you need.

Has anyone here ever done this? I'm sure the shims are hardened. I wonder how tough it would be to gain the clearance to get them back in spec?
I think I'd rather just buy them..............that's too much work :)
I have done this, but not on FJR shims. Years ago, I worked in a tool and die shop. Grinding hardened steel was something I did every day on my surface grinder. This highly accurate machine made quick work of resizing about 8 or 9 valve shims from my Suzuki GS1000. I did note that from the factory, every one of the shims measured slightly thicker in the middle than at the outside edges. I've forgotten as it's been many years, but I'm thinking that these shims were perhaps 3/4 of an inch in diameter. I'm also thinking there was perhaps less than 1/2 of a thousandth difference when measuring the thickness of various points across each shim. The surface grinder could grind them in less than a minute for each one. The new finish cut by the grinder was just as smooth as the original from the factory, and of course, it had no effect on the hardness or performance of the shim. I checked this on our shop hardness tester just in case. The shims worked just fine in the bike.
Gary from Tampa

 
If you are going to sand on a shim to take it to the next half size smaller, do the next guy that owns your bike a favor...

Sand the number side, do not make a thin shim and keep the number intact.
 
It would be like putting kerosene in the vodka bottle and leaving the label alone.
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Also a suggestion about sanding, place a bit of 2 face tape on your finger and use it to keep the shim under the finger tip. Use a figure eight pattern, reverse it after a few strokes. Rotate the shim every so often. The idea is to remove the same amount of material off the whole face. You want parallel faces, not a wedge. A micrometer would be a good tool to have when doing this.

Good luck, personally I would try the service department collection first.

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Brodie
Anybody know if the shims are hardened right through or just case hardened? I suspect right through but if just hard on the surface, sanding might not be such a great idea.

Ross
Case hardening is considerably thicker than anything you could ever take off with sandpaper.Gary in Tampa: former machinist

 
Finally received the parts (shims and CCT). However, lesson to be learned.....always remember where you left your engine parts before you grab a sheet you used to wrap them in from the work bench.......lets just say I'm glad I caught the cam before it hit the floor....what a nightmare!

 
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I have ground valve shims for years, albeit on KLR's. Easiest to do on a surface grinder, just remember to grind the number side of the shim so it won't be confused later as a different size. Also I put the ground side down in the bucket so the cam won't wear the shim if the case hardening is ground away. I also use a little sand paper afterwards to take the sharp edge off the bottom of the shim so it will fully seat in the bucket.

 
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