My neice has reciently become an avid unicyclist, taking my old 20" Schwinn on
long rides. She keeps riding off the right pedal. I checked to make sure the
pedals are on the correct sides and they are. I’m worried that perhaps because
of this happening damage has been done to the crank arm. So, I have two
questions, first how easy is it to find a cottered crank (set) and second, if
there is no damage to the crank how can I keep the pedal from riding loose?
Re: Cottered Crank replacement
hartmame wrote:
>
> My neice has reciently become an avid unicyclist, taking my old 20" Schwinn on
> long rides. She keeps riding off the right pedal. I checked to make sure the
> pedals are on the correct sides and they are. I’m worried that perhaps because
> of this happening damage has been done to the crank arm. So, I have two
> questions, first how easy is it to find a cottered crank (set) and second, if
> there is no damage to the crank how can I keep the pedal from riding loose?
This is a very common problem and there are a number of possible causes.
The worst possible case is if the actual axle has become worn and is no longer
square. Unless you want to continually put it back on a replacement axle will be
required. This is a big operation as it requires,
a) finding a replacement
b) respoking the wheel
If it is the cranks themselves that have become worn there are a couple of
options. First try removing the cranks, rotating them through 90 or 180 degrees
and putting them back on. This may fix the problem.
Otherwise you can replace the cranks. This is often not too hard to do although
you probably want 127mm or 125mm crank arms which may be a little hard to get
hold of (And make sure you get a Left and a Right, not just two lefts). Check
out bike shops that deal with BMX parts or get hold of someone who deals in
unicycles.
Another possibility is to use loc-tite (NOT the permanent kind). Make sure you
put the cranks on really tight before hand. I bike shop should be able to do
this for you (its probably not worth buying a tube yourself).
Happy hunting, Peter
–
University of Waikato 61 Nevada Rd Peter Bier
pjb10@cs.waikato.ac.nz Hamilton Unicyclist, juggler and
mathematician. (07) 856 1103