Square Taper Crank Installation and Maintenance
Purpose of this article
To provide detailed instructions for the proper installation of square taper cranks onto unicycle wheels, and for their continued maintenance after installation.
Importance of this article
Improper installation or maintenance of square taper cranks can quickly lead to ruin of the cranks, and possibly of the axle, of a unicycle wheel. The cost in time and money of ruining these parts is far greater than the cost of the tools, materials, and time required to do the installation properly and to maintain the cranks once installed.
This procedure is the only procedure approved by LiveWire Unicycles for installation of square taper cranks onto LiveWire wheels. Use of any other procedure voids the warrantee of the cranks and/or wheel. Spending $90 on a torque wrench is nothing compared to the hundreds you spent on that great wheel.
Freshness of this information
This procedure is the best available as of 10 July 2005, working with many different sources from the bicycle and unicycle world, including experience with many unicycles and unicycle wheels. See also References below.
Summary of Procedures
Installation
(1) Clean all surfaces with degreaser
(2) Grease axle taper (all four sides) with bicycle grease
(3) Install crank by hand on correct side of wheel
(4) Add two drops of blue {medium-strength} thread locker to axle threads (not red {high-strength} thread locker, unless you like using a blowtorch on your uni)
(5) Install crank nut/bolt by hand
(6) Torque nut/bolt on to 40 ft-lbs using appropriate torque wrench
(7) Install dust cap
(8) Repeat on other side
Maintenance
Whenever cranks feel loose, whenever crank nut/bolt feels loose, whenever you are not confident in the cranks, or whenever you detect corrosion starting to work on your cranks:
(1) Remove dust cap
(2) Remove axle nuts/bolts
(3) Remove cranks using crank puller
(4) Reinstall cranks using procedure above
In the Field
If you are out on a ride and detect crank or nut/bolt looseness, tighten the nut/bolt firmly, but not hard. When you return from your ride, completely remove and reinstall the cranks using the above procedure. Should these steps prove ineffective, replace the cranks before your ride again, or you risk ruining your wheel. If you are on a ride, and can't keep the cranks tight, discontinue your ride immediately (i.e., walk out!), and replace the cranks before you ride again, or you risk ruining your wheel.
Detailed Procedure with explanations
(coming soon)
Sheldon Brown's presentation of a Jobst Brandt article on installing bicycle cranks
Copyright © 2005 LiveWire Unicycles
Last modified:
08/01/2005