MTFCA Forum

I installed Rocky Mtn brakes on my 1925. Seems I have to shim the axles to install wheels. I don’t like using shims - are there other options?

The alternate may be new axles and hubs. Shims for proper hub fit to axle taper are available from the vendors.

Some of the vendors also sell new axle shafts that are made 1/16" longer than stock to reduce or eliminate the need for shims.

Axle stretch.
The axle gear is pushed down to remove the half round keepers plus about 1/2". The keeper relief in the axle is widened about .10".
(away from the gear) Using a lathe with a parting tool. Gear is pressed back on to the deeper position.
The gear woofruff key will need a trim @ the gear face as to not chew up the hyatt cage.
Your axle is longer without buying a new one.
This is something I do for every rear end rebuild to compensate for worn hub & axle tapers to retain original axles.

Speedy,
One thing you did not mention is the spacer between the axle ends inside the carrier. you need to replace with a thicker one to keep the axles from moving inward putting strain on the gears.
I personally would recommend either the shims at the tapered end of the axle or new longer axles. Another thing to consider is the taper inside the hubs. If they have been run loose in the past, there is a possibility that they are also worn.
Norm

Norman Kling wrote: ↑

Fri Oct 20, 2023 11:00 am

Speedy,
One thing you did not mention is the spacer between the axle ends inside the carrier. you need to replace with a thicker one to keep the axles from moving inward putting strain on the gears.
I personally would recommend either the shims at the tapered end of the axle or new longer axles. Another thing to consider is the taper inside the hubs. If they have been run loose in the past, there is a possibility that they are also worn.
Norm

Of coarse the spacer(s) between the axles need to be refit. Thats the part of every axle overhaul.

I also HATE using shims. I have seen to many flake apart & cut into the outer seal. Now you have greasy brake shoes.
I do not recommend shims as a permanent fix.
I also lap the tapers for a proper fit. Its the taper that holds the wheel on tight, not the key.
Also remember to get the axle nut real tight & re-check several times in the first 200 miles or so until the taper takes a set.