>“George B.” <gbarnes82@hotmail.com> wrote in message
>news:99ipru$74f$1@news.iastate.edu…
>> The opportunity to purchase an old 20" Schwinn for about $40 has presented
>> itself. It is not in the greatest shape, needing a new seat and probably new
>> wheel/tire/cranks. My questions is whether it is worth purchasing this
>> unicycle and putting the money in it to make it rideable.
“John Drummond” <unicycle@bellsouth.net> wrote:
>Hi George. If it has cottered cranks, you might want to resist this temptation.
>Cotterless is much, much better.
Yes, a cotterless hub system is superior to the older cottered hub system.
However, a cottered hub system can be just as reliable as a cotterless hub
system. A cottered hub system just requires more maintainence (and/or different)
skills. A good bike shop should be able to handle either.
Cottered hub system maintainence:
Selection of a set of cotter pins that are thick enough to properly fasten the
crank to the axle is critical. The cotter pins must be pressed in with a special
tool or pounded in with a hammer so that they are extremely tight. A critical
error often made by novices and even some bike shop mechanics is trying to
tighten the cotter pin by simply tightening the nut. Wrong! This may work on a
bicycle, but definitely not a unicycle where torque is applied in both
directions to maintain forward/backward balance! The nut is tightened after the
cotter pin has been fully pressed or hammered into its final position. The nut
should be made as tight as possible since it keeps the cotter pin in the
extremely tight position that keeps the crank firmly attached.
If you pound a cotter pin on with a hammer, be sure to support the hub directly
using a workbench and/or block of wood. This will avoid stressing the spokes
that will occur in the absence of such support.
To avoid cosmetic damage while hammering a cotter pin, one can go to the
extremes of using a brass hammer, or a regular hammer and vice-grip holding a
brass “pounding block” or even a copper penny in a pinch.
Sincerely,
Ken Fuchs <kfuchs@winternet.com