Hub & Cranks
Unlike a bicycle, a unicycle has just one hub; it is at
the same time the centre of transmission, and so quite
unique! It is exposed to much greater stresses than
bicycle hubs, bearing both the weight of the rider and
the entire force of transmission. These forces can be
compounded by aggressive or extreme riding.
Standard unicycles have a square-taper crankshaft,
which is sufficient for normal riding. Crankshafts made
of better-quality steel alloys, like Cro-Mo, are tempered
to be harder and stronger.
QU-AX
unicycles with such
crankshafts are colour-coded:
QU-AX
black and silver hubs are square-taper, ISIS-
splined hubs are red or yellow and Race hubs are blue.
Q-Axle-hubs are anodized red (shiny). Yellow hubs are
tougher than red ones, but all red, yellow and blue
hubs are made from a specially-tempered steel. The Q-
axle-crank-system has a wider axle and pinched cranks
- which is the best way to combine strength, lightweight
and durability.
ISIS crankshafts end not in a square-taper but in ten
splines, giving a much greater surface area to transfer
torque safely from the crank-arms to the hub. They also
have a large diameter and bigger bearings.
The
QU-AX
ISIS crankshaft is a standard 10-spline ISIS
crankshaft, but there are also brands making 8 and
48-spline crankshafts. The ISIS standard was established
by the bicycle industry. The Q-axle standard follows the
current bicycle-technique evolution.
The yellow
QU-AX
hub is almost legendary among
Trial-riders as the first genuinely solid hub. The first
front-flip on a unicycle was
done on a yellow
QU-AX
hub!
All high-end
QU-
AX
unicycles are
built with up to 36
to 48 spokes for stiffness
and resilience when
performing tricks or for extreme riding.
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