How to use a Park Tool CRC-1 Race Crown Cutter
The following information was derived from the Park Tool Company instruction Manuals
The Park Tool CRC-1 Crown Race Cutter is a precision tool designed to mill and/or face a fork's crown race
seat to precise dimensions. Milling and/or facing the crown race seat insures a proper press fit of the crown
race, as well as proper performance and longevity of the headset.
A unique feature of the CRC-1 is its use of two adjustable bushings, insuring a precise fit and accurate cut on
any 1" or 1-1/8" fork - even those with externally butted (bulged) fork columns.
The CRC-1 includes the body/handle assembly, two adjustable bushings, and high speed steel cutters to mill
and face 26.5mm and 27.1mm crown race seats on 1" forks and 30.1mm crown race seats on 1-1/8" forks.
Because this is a precision cutting tool, all components should be used and stored with extreme care.
Components should not be dropped, misused, or abused in any way. The cutters should be periodically
sharpened by a qualified technician for optimum performance and long life. Components should be cleaned
and wiped with an oily cloth or rust inhibitor before storage, particularly in a damp or humid environment.
We strongly advise against using the CRC-1 on any crown race seat that is chrome plated, as it will dull the
cutters very quickly and compromise performance. If a chrome-plated fork has a crown race seat that needs
to be milled and/or faced, we recommend removal of the chrome.
1. Measure the inside diameter of the crown race being installed and select the proper size cutter. The
CRC-1 includes two double-sided cutters. Part #845 (used on 1" forks) has a 26.5mm cutter on one side
and a 27.1mm cutter on the other. Part #846 (used on 1-1/8" forks) has a 27.1mm cutter on each side.
If the inside diameter of the race is between 26.3mm and 26.4mm, use the 26.5mm cutter. If the inside
diameter of the race is between 26.9mm and 27.0mm, use the 27.1mm cutter. If the inside diameter of the
race is between 29.9mm and 30.0mm, use the 30.1mm cutter. Position the cutter in the body/handle assembly
(#841) and tighten the set screw (#609), making sure the set screw is in line with the positioning point in
2. Select the proper adjustable bushing. Use the black bushing (#843) for 1" forks and the blue bushing (#844)
for 1-1/8" forks. Unthread the cap/nut (#842) from the top of the handle assembly, drop the bushing in the
body of the handle assembly, and re-install the cap/nut. At this point, do not tighten the cap/nut. Tightening
the cap/nut before installing the tool on the fork will damage the bushing.
3. Position the CRS-1 onto the fork column and tighten the cap/nut just until there is no play between the tool
and the fork.
4. Mount the fork onto a front wheel. With the wheel on the ground, grasp the wheel between your legs in order
to stabilize the fork.
5. Liberally apply cutting oil or cutting fluid to the cutter and to the fork's crown race seat. General purpose oils
are not suitable lubricants and use of them will significantly shorten the life of the cutter and reduce the
performance of the tool. Use a suitable cutting oil or cutting fluid for the material being cut. We recommend
the use of Park Tool Cutting Fluid, CF-1. Park Tool Cutting Fluid is a high quality, environmentally safe
cutting fluid that can be effectively used on all metal (except magnesium).
6. Lean over the wheel and fork and apply downward pressure while turning the tool in a clockwise direction.
Turning the tool in a counterclockwise direction will damage the cutter. As the tool cuts down the crown race
seat, continually add fresh cutting oil or cutting fluid. Continue turning the tool clockwise until the cutter
contacts the bottom of the crown race seat and a flat, smooth, evenly faced surface is created.
7. Clean the fork and the tool completely. The fork is now ready for installation of the crown race.