Oddball Valve Shim Sizes

[Fred W]

No flames, just a difference in philosophy.

I set mine to the 70th percentile as a means to extend the time between required re-shims, which that will accomplish. Technically you are correct that setting the clearance to the minimum clearance will allow the largest valve rise, however the difference we are talking about here is only .05mm of lift (difference between .15mm min spec and my .20mm "70% target")

The total valve lift is defined by the cam grind. The cam lobes are 8.053mm tall. (Interestingly, both intake and exhaust lobes have the same dimensions). Subtracting the clearances from the lobe dimension means that the total valve lift will be 7.903mm @ .15 clearance vs 7.853mm @ .20 clearance or a difference of 0.6% less lift at the larger clearance.

The valve lift does not directly translate into improved intake flow because it is not the only limiting factor to the flow. The difference in engine performance will be (is) negligible.

 

[audiowize]

For reference on the valve sizes, I had shims ranging from 1.82mm to 1.92mm. If I did it over again, I would've popped out all the shims to see what the full spread was.

I think if you stock sizes between 1.725 and 1.9mm in 0.025mm increments, that would be a rockin set for the FJR. That's about $80... not all that much more than the Hot Cams.

(MC - want to nab some Connie shims from my kit?)

 

[MCRIDER007]

For reference on the valve sizes, I had shims ranging from 1.82mm to 1.92mm. If I did it over again, I would've popped out all the shims to see what the full spread was.
I think if you stock sizes between 1.725 and 1.9mm in 0.025mm increments, that would be a rockin set for the FJR. That's about $80... not all that much more than the Hot Cams.

(MC - want to nab some Connie shims from my kit?)

Thanks for the offer but I would not have any use for them.

Since the C14 is now a backup bike, the last valve adjustment will probably last longer than my riding career.

 

[BakerBoy]

Does the FJR use 7.48mm diameter shims, or 9.48mm diameter shims?

I bought a Hotcams shim kit, which has 3 of every size in increments of 0.05mm, from 1.20 to 3.50mm, for ~$90. In hindsight, I wished I had spent $90 for a more fitting quantity of shims only in the thickness range needed for my ST1300, and wish I had 0.025mm increments available. I found myself needing shim thicknesses and quantities that the kit didn't have, and ended up trading shims around to get all in spec (and replenishing the kit with additional 0.025mm increment shim thicknesses in the range needed).

Following up on a post above by Old Guy: Yes, Honda offers individual 7.48mm diameter shims in increments of 0.025mm thickness.

Honda 7.48mm diameter shims are numbered sequentially as follows:
>>1.200mm, part number 14901-KT7-013
>>1.225mm, part number 14902-KT7-013
......through
>>2.900mm, part number 14969-KT7-013

 

[rbentnail]

9.48

 

[Old Guy]

This page offers 1.80 and 1.90.

 

[bergmen]

This probably goes without saying but if a camshaft is removed to adjust one or more clearances, all of the buckets should be lifted on that side (intake and/or exhaust) and shims measured for each valve whether they need adjusting or not. With a map of these shim sizes, you will know what shim you will need the next time an adjustment is necessary without pulling the cam shaft first.

I just wish the factory would supply an original shim map when they set up the new engine so you would know what is in there before a cam-ectomy.

Dan