the rec.sport.unicycling maintainance FAQ .v0.1.7
edited and compiled by evilewan.
Index
What is a FAQ?
How should i contribure to the maintainace
FAQ?
How should i put on my new set of cranks
(my unicycle has a cotterless/square taper hub)?
The bottom gear on my giraffe
unicycle keeps unscrewing itself, what can i do to stop it?
How much should I inflate the tire?
How do i do an air seat conversion on my miyata
seat?
My
wheel isn't centered in my frame. What's wrong and how can I fix it?
How should
i remove and service (or replace) my bearings?
How
should i remove my cranks?(my unicycle has cotterles/square taper cranks)
I'm trying to take
my miyata seat apart and the bolts spin around without unscrewing, what on
earth can i do?
My shwin girrafe
bottom bracket needs serviced, how can i do it myself?
My lolipop style frame
has died, what can i do?
Magura brakes, how the
hell do i service these things?
Q.
What is a FAQ?
A.
Its a list of Frequently Asked Questions and their answers.
Q.
How should i contribute to the maintainance FAQ?
A.
Send your article to evilewan as a private message. idealy as an
attachment in plain text (.txt) plus seperate pictures in .png or .jpg
format preferably .png because it dosent have patent issues like .jpg
.gif etc.
if you want to post an improved version of an article then send me
the complete article not just your revisions.
and any new pictures (but not the old ones)
i would prefer to only replace articles with a new version if the
old one is flawed or the author of the previous article prefers the new
one.
if you post a usefull article on the forums then i may put it in the
FAQ, if i do this and you don't want your work in the FAQ then tell me
and i'll remove it imediately
Q.
How should i put on my new set of cranks (my unicycle has a cotterless/square
taper hub)?
John Childs has posted his recipe several times. His requires
a special tool for one part of the process. I don't always grease the
tapers, especially if I'm putting aluminum cranks on a steel axle but
that doesn't mean I'm right. John ALWAYS does.
1.) Put the LEFT crank on the LEFT side of your uni.
2.) Put the RIGHT crank on the RIGHT side (they are marked L and
R).
3.) Place a piece of wood on the HARD (concrete) ground or floor
(the pieces of wood are to protect your cranks and should be centered
under or over the axle).
4.) Balance the uni on the board on one of the cranks (center the
axle, not the crank, on the board).
5.) Place another piece of wood over the other crank (center over
the axle).
6.) Smack the top piece of wood with a hammer (HARD) DIRECTLY over
the CENTER of the AXLE.
7.) Flip the uni over and do the same thing.
8.) Install nuts or bolts, whichever are appropriate, and tighten.
9.) Install the LEFT pedal on the LEFT crank and the RIGHT pedal
on the RIGHT crank. They are marked L and R. The LEFT ones are LEFT HAND
THREADED and will seem to go on backwards. As you look at the outer edge
of the LEFT pedal toward the LEFT crank the pedal axle will turn COUNTER-CLOCKWISE
to tighten.
10.) Ride a short distance and retighten the crank nuts (bolts) until
they no longer require tightening between rides.
11.) NEVER ride a uni with LOOSE cranks or pedals!
__________________
-Greg Harper
see also sofas article here: http://londonunicyclingclub.ca/pedalbearings.htm
with pictures.
i'm with the "whack the cranks on hard with a mallet" school of thought
ymmv.
e.e.
Q.
The bottom gear on my giraffe unicycle keeps unscrewing itself,
what can i do to stop it?
A.
This is a well known problem that occurs with chain drive unicycles.
Loctite or lock rings are only going to result in a temporary fix.
The only solution is to weld the bottom sprocket to the hub.
The hub has to be steel, not alloy.
Spin the sprocket as tight as you can onto the hub
Remove axle, bearings, dust covers, tire, tube, rim strip, etc.
Have a welder weld the sprocket to the hub (Being careful as they
go to weld
where the threads meet.)
Replace the axle, bearings, etc., etc.
Install the wheel and tighten the chain
After that, no chance of getting hurt. If you don't do this, ride
at your
own risk !
I don't sell a tall unicycle that hasn't had the sprocket welded...
and no one else should either !!!
Darren Bedford
Q
How much should I inflate the tire?
A.
this depends what kind of riding your doing and how heavy you are.
1. Freestyle
Generally, ( freestyle) unicyclists overinflate their tires by as
much as 50% and sometimes even more. However, if one is learning
to ride on a slippery surface (gym floor) and wheel twisting
becomes difficult to control, the tires can be underinflated to
increase the tire area that comes in contact with the floor. This
will make wheel twisting easier to control. Once one has learned
to ride, the tire should be inflated to at least the recommended pressure.
Try to get 40-50 psi or more rated tires and you may
overinflate these as well if you like. However, a 32psi tire
will work fine, too.
Ken Fuchs - kfuchs@winternet.com
2. Trials
trials tyres like the monty and onza are probably the most noticable diferance
on a trials uni. they are designed to hold lots of air to give extra
bounce and softer landings. they normaly have a double side wall to allow
the tyre to be run at a much lower pressure rating. giving psi ratings
is pretty pointless here, you realy have to find your own perfect pressure
by trial and error.
your tyre must be hard enough to stop the tyre folding over when you land.
and you want it to be soft enough to give you a bit of extra bounce
when you pre-hop.
e.e.
3.Muni
Tire/tyre pressure for Muni riding varies much the same way
as Trials riding. pressure needs to be set depending on the type of terrain
being covered. some general rules: set the pressure to that you bottom out
once a ride, or once in a blue moon(comes from the mountain bike shock rules,
should be hard to bottom-out, but not impossible WARNING: not for wimpy
innertubes, or they will get a snakebite puncture). three other things
to weigh when setting tire pressure: personal preferences, duh; roll-off:
this is where the tire flops over the side of the rim, happens a lot on
transversals, this will make your ride more unstable and isnt good for your
tire--pump up the tube a bit till this doesnt happen; and terrain(to be
covered next)
Some more specific rules:
1. sand: set tire pressure low to get more traction.
2. roots: varies on how you traverse them, set pressure higher if you
hop on them, lower if you roll over them. 3. snow: cold weather will make
air contract, so pump up your tube a little to keep same pressure(remember
to let pressure go later on).
4. mud: pressure low to get some grip.
5. ice: good luck! really low pressure for traction, high pressure
for sliding(go to do a forward hop, but dont jump up)
RancidFlannel
Q
How do i do an air seat conversion on my miyata seat?
A
There is a great article about it by Rick Bissel here: http://unicycling.org/airseat
and some more pictures and ideas from Bruce Edwards (yoopers) here: http://www.unicyclist.com/gallery/Miyata-seat-conversion?&page=1
Q
My wheel isn't centered in my frame. What's wrong and how can I fix
it?
A
Several things could be wrong.
#1: One side of your fork could be longer than the other. This is
common with many Taiwanese frames, such as the Yuni (Nimbus II UK) and
United with main cap bearing holders {or the semcycle xl,}, and can be
easily fixed by putting shims between the top of the bearing and the bottom
of the fork. I use strips of aluminum soda can as shims. The basic idea
is to use shims to add length to the shorter side of the frame. Here's
step by step instructions.
Diagnosis:
Remove the main caps, but leave the wheel in the frame. Get at a good
angle to see the wheel between the legs of the frame, and spin the wheel.
If the wheel is closer to one side of the frame consistently, than try
taking the frame off, turning it around, and putting it back in the wheel.
See if the wheel is still off to the same side. If it's off center to the
other side, than your wheel is dished, and that's a different problem.
If it wobbles back and forth while it spins, than it's out of true. If it
looks just like it did before you turned the frame around, than you need
to shim it.
Fix:
Figure out which side of the frame is closer to the wheel. This is
the shorter side. Remember which side it is
Remove the wheel from the frame.
Cut out pieces off soda can to fit in the top of the bearing holder.
Depending on how bad it is, you could need 7 or 8 pieces.
Put the shims in the bearing holder attached to the shorter side of
the frame. Put the wheel in the bearing holders on top of the shims.
You may have to bolt the main caps back on to the frame before you
know if you've put the correct number if shims in, because they compress
a little when you tighten the main caps. Add or remove shims to get the
wheel as close to centered as possible.
I've used that fix on several of my unicycles, and it has never caused
me any problems.
#2. Your bearings aren't centered on the axle. If your bearings have
a press fit like on a Suzue hub, they may have slipped. If you have a Profile
hub or something with a similar design, having a different number of spacers
on each side of the axle will cause this also. This will probably be addressed
by John Childs if you ask him. I don't have any experience with it.
#3. Your frame could be bent. This is not very common. You may be
able to bend you frame back, or possibly use the shim fix. If not, buy
a new frame.
Ben Plotkin-Swing. www.benps.com
Q.
How should i remove my cranks?(my unicycle has cotterles/square taper
cranks)
A.
Sofa has written a fantastic article here:http://londonunicyclingclub.ca/cranks.htm
Q.
How should i remove and service (or replace) my main axle bearings?
A.
Sofa's article here http://londonunicyclingclub.ca/bearings.htm
has all the answers
Q
How should i service my pedal bearings?
sofa has done that too, look here: http://londonunicyclingclub.ca/pedalbearings.htm
Q.
I'm trying to take
my miyata seat apart and the bolts spin around without unscrewing, what
on earth can i do?
A.
Bruce Edwards (yoopers) posted the folowing picture guides which may be
of some help:
http://www.unicyclist.com/gallery/Miyata-seat-cover-removal
http://www.unicyclist.com/gallery/threaded-rod-alternative
Q
My shwin girrafe
bottom bracket needs serviced, how can i do it myself?
A.
Steve DeKoekkoek (UniBrier) has done it, see his pictures here: http://www.unicyclist.com/gallery/schwinngiraffebottombracket
Q.
My lolipop style frame
has died, what can i do?
A.
look at this article by Gardner
Buchanan <gbuchana@rogers.com>
http://unixcomputer.net/new-photo/frame-broke/
Q.
Magura brakes, how
the hell do i service these things?
A.
apart from having a unicycle with brake boses on the frame, look at this
site,:http://www.execulink.com/~dtierney/wmc/Magura/contents.htm
Unanswerd Questions.
links to other faqs would be good too, we don't want to keep all the
glory for ourselves do we?
how to install the cranks/bearings on a profile hub
how to true a wheel
how to build a wheel
a guide to bearing sizes?