1. Setting Up the Fork

A BMX fork, is made with cylindric tubing and don't have the lower bending at the dropouts. The dropouts ar made with two plain blades welded to the tubes. The first operation is remove the dropouts.

BMX type fork

The fork with the dropouts and brake pivots removed

The fork I've used, don't have the cantilever brakes pivot. The next operation is made longitudinal cut on the top tube, to install the saddle tube clamp.

The last operation, was set up the shape of the fork "legs" to mount the bearings. The bearings mount is made directly over the tube, fixed by "U" bolts and clamps.

Front and Side views of the bearings mount

2. Making the Axle

The first two versions of the axle were bad succeeded and. In both versions, I've tried to use modificated bike hubs. A permanet gap between the axle and the hub, made impossible the utilization of the unicycle. The right version (the third...) was born when I've decided to made an unicycling specific axle. If you are planning to build an unicycle, don't try to use a bike hub... It will be pure time lost.

The unicycle axles, are just a solid axle with two flanges welded. To made the flanges, I've used two washers with 5/8" inner diameter and 2" outer diameter. An old 2" hub flange was used as template to drill the spoke holes (18 holes each flange). This operation needs some patience to do, but it doesn't so boring...

The axle was made with a 7/8" piece of 1045 steel, conformed in a lathe. The flanges was welded with a 10 degrees offset to meet the right spoke holes position.


Ready Axle Diagram.

The most common cranks standard, is the square hole. To made the axle with square extremes, isn't an easy task. 125 mm cranks are almost inexistent at the brazilian market and I found two 135 mm cotter cranks used in a moped (the Caloi Mobylette)

These cranks turns the task so easy, because the cotter cuttings at the axle may be made with a simple file. See the result at the diagram below


Cotter cutting diagram.

With the axle ready, the last operation was lace the wheel (stainless steel spokes laced with the cross-4 pattern) and true it

3. The Saddle

Unicycle saddles are very special things. They are not modified bike saddles and I've decided to buy an unicycle saddle and not "reinvent the wheel"...