An Excel Valve Clearance Spreadsheet

[ULEWZ]

I put an excel spreadsheet together for my dirtbike and posted it on Thumpertalk. Definately not as spiffy as yours, but I did include a "what if" calculation on mine. With the measured clearance, existing shim, and recommended clearance, you can enter shim sizes to see where your clearance will end up. This is handy since the shims in the Hot Cams kit have big differences between shims, and sometimes you need to make a compromise. Too high, or too low. Just a thought if you want to get frisky.

Here is a link: https://www.thumpertalk.com/topic/764247-modified-shim-calculator-hope-it-works/

 

[Fred W]

The Hot Cams kits come in .05mm increments (same as the stock shims). Sandpaper and a micrometer are your friends here.

The "what if" feature is included in the Billy Yamafitter's spiffy spreadsheet too.

 

[MCRIDER007]

The Hot Cams kits come in .05mm increments (same as the stock shims). Sandpaper and a micrometer are your friends here.
The "what if" feature is included in the Billy Yamafitter's spiffy spreadsheet too.

I had access to a Hot Cam kit and used Jake Wilson to fill in the gaps since they sell shims in .025mm increments. I don't think anyone recommends sanding shims but I haven't heard of any problems from those that have done it.

 

[wheatonFJR]

...I don't think anyone recommends sanding shims but I haven't heard of any problems from those that have done it.

Besides being a pain in the ass, what could be the possible downside?

 

[Fred W]

I'll let you know in another 20k miles...

 

[MCRIDER007]

...I don't think anyone recommends sanding shims but I haven't heard of any problems from those that have done it.

Besides being a pain in the ass, what could be the possible downside?

That the shim does not have uniform hardness throughout and will start to wear if the outer layer is sanded away.

 

[Fred W]

...I don't think anyone recommends sanding shims but I haven't heard of any problems from those that have done it.

Besides being a pain in the ass, what could be the possible downside?

That the shim does not have uniform hardness throughout and will start to wear if the outer layer is sanded away.

There is no friction against the shim, only pressure. It just sits as a spacer under the bucket, which does get the friction and potential for wear from the cam swiping across it, and the valve stem, whose motion is only up and down so no potential.

The chances of it "wearing" are slim to none. I do not believe these shims are even hardened based on how easy they are to sand down.

 

[MCRIDER007]

...I don't think anyone recommends sanding shims but I haven't heard of any problems from those that have done it.

Besides being a pain in the ass, what could be the possible downside?

That the shim does not have uniform hardness throughout and will start to wear if the outer layer is sanded away.

There is no friction against the shim, only pressure. It just sits as a spacer under the bucket, which does get the friction and potential for wear from the cam swiping across it, and the valve stem, whose motion is only up and down so no potential.

The chances of it "wearing" are slim to none. I do not believe these shims are even hardened based on how easy they are to sand down.

I am just the messenger on this one since I don't have any first hand expertise.....but based on all the warnings I have read saying not to sand down the shims (and this may not be applicable to shim under bucket valve trains), my preference is to buy the shims in the smaller increments to get the desired clearances.

Back to the original question.........does anyone else have input on the FJR's installed shim sizes?

 

[ULEWZ]

The Hot Cams kits come in .05mm increments (same as the stock shims). Sandpaper and a micrometer are your friends here.
The "what if" feature is included in the Billy Yamafitter's spiffy spreadsheet too.

You are right. The what if calculation is there, I just missed it because I failed to read the notes and only relied on my poor interpretation of the text by the boxes. Very good.

 

[VMaxChuck]

Thanks for the spreadsheet! Hope it comes in handy for ME on a future purchase!!

 

[Constant Mesh]

One might assume that the lifters rotate a bit as they move up and down. So there may be some rotary movement between the shim and lifter. The thickness marking on the shim typically faces up against the lifter. The markings on most of the shims I've inspected have all but disappeared.

 

[Fred W]

One might assume that the lifters rotate a bit as they move up and down. So there may be some rotary movement between the shim and lifter. The thickness marking on the shim typically faces up against the lifter. The markings on most of the shims I've inspected have all but disappeared.

You are correct, the buckets do tend to rotate, but the rotation would happen when they are unloaded. There is nothing forcing them to rotate, they just sort of do it on their own, so no real wearing at the surfaces. The markings are just stamped ink, so the fact that there is ever any of the original marking left on them at all is evidence that there is no real friction or wear going on here.

 

[RaYzerman19]

If you buy the Hot Cams shim kit, you'll have a whole mess you'll never use, and one of the two boxes can be put on the shelf as a paperweight.... Just buy a few individual shims, say 3, 4, or 5 each around the 175-185 mark and you'll be good to go.

https://www.rockymountainatvmc.com/p/43/53/210/922/-/26634/Pro-X-Valve-Shim

https://www.rockymountainatvmc.com/p/43/53/210/922/-/26634/Pro-X-Valve-Shim

 

[PhilJet09]

Thanks for making this spreadsheet. I'm in the process of doing my second valve check and this makes it easier.

 

[MrM0t0]

Does anyone have this spreadsheet? The original link appears to be dead. TIA

 

[thomasgif]

I remade it a couple weeks ago. PM me your email and I'll send it along.

 

[MrM0t0]

Thanks! PM Sent

 

[Fred W]

Original is here:

Valve Clearances Spreadsheet

(I was hosting that spreadsheet on a comcast web account that no longer exists. The first post is not mine so I cannot edit the link)

 

[MrM0t0]

Fred - What grade of sandpaper did you use? I tried 220 and didn't even make a dent!

 

[Fred W]

It was about the same as that. What kind of sandpaper are you using? Wet or Dry?

I was using some woodworking finishing paper. I'd have to go find my old posts to see what the grits were.

It does take some persistence.