Honda CRF Valve Shim Calculator

Looking to shim your Honda CRF450R/CRF450X valves to their correct tolerances? Use this valve shim calculator to make the job easy. It's set up with shim specs for the CRF450 but you can change those and use this calculator for the Honda CRF250R and CRF250X as well. At the bottom it has the Honda part numbers for all the available shims as well a link to the Hot Cams Shim Kit.

Inches to Millimeter Conversion:

NOTE:

• Make sure of the correct shim thickness by measuring the shim by micrometer.
• Reface the valve seat if carbon deposit result in a calculated dimension of over 3.000 mm.
• 73 different thickness shims are available from the thinnest 1.200 mm thickness shim to the thickness 3.000 mm thickness shim in intervals of 0.025mm.

NEED SHIMS? Below are the Honda part number for shims. You could also purchase the Hot Cams Shim kit listed in our catalog or just click here. You can also purchase individual shims from our OEM parts website at www.yeltrik.com.