PopeSamXVI said:*My wheel bent today. So much that it jams itself on the rim. I
suppose I should have it trued, but this is the second time. Should I
just buy a new rim? *
Perhaps. How far has it bent? One centimeter? Five?
Your best option is probably to keep saving for a new unicycle and true
it yourself. Go to a LBS and get a spoke wrench and a crank puller if
you don't have one already. Go to a good LBS (defined as one with
helpful mechanics) when they aren't busy and have them show you how to
use the tools.
1) Remove the cranks. (Note - with a little charm this can be done with
the help of the LBS mechanics as they show you how to use the puller.)
2) Take the wheel off the unicycle, deflate the tire and take it off the
rim. Put the wheel back on the uncycle.
3) Rig up some sort of indicator to let you see how true the rim is.
Some people use zip-ties, others use tape with a flap sticking out,
others use bailing wire. Doesn't really matter as long as it gives you
a good visual reference.
4) Turn the unicycle upside down and brace it somehow. Some people take
the seatpost out and plunk the seat tube down into something. Others
just get a friend to hold the frame. The setup doesn't have to be
particularly rigid but it should be stable.
5) Sit in the plane of the wheel (hub hidden behind the rim) and spin
it. Watch what it does. Use the spoke wrench to tighten and loosen the
spokes so that a) the rim is round and b) the rim is flat, and c) the
spokes are really tight so it won't bend again. This is an art, not a
science, so take your time. Never tighten or loosen a sopke more than
half a turn at a time. Quarter turns are better. Really good wheel
mechanics can true and tension a wheel in 5 to 10 minutes, but if it's
your first wheel it might take a couple of hours. Plan on a few breaks
and some sanity-reparing activites. If you've got a good LBS then
periodically take what you've got so far to them and ask their advice.
(Trust me, if the LBS is worth anything they will be happy to help as
long as you pick a slack time. I used to be a mechanic.)
6) It's possible that the rim is bent beyond repair, in which case you
will need a new rim, but only the rim. It's stronger and less expensice
to put a good rim on your old hub than it would be to buy a cheap-o
wheel. De-tension the old wheel by loosening the spokes in multiple
passes (again, never more than half a turn at a time) until they are
completely slack. Tape the new rim to the old one making sure to line
up the hole for the valve stem. Transfer teh spokes to the new rim,
remove the old one and start to tension the wheel.
7) Put everything back together and ride off on your virtually new
wheel.
--
cyberbellum - Level 1.0 rider!
Optimists think the glass is half full. Pesimists think the glass is
half empty. Engineers think the glass is too big.
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