Harware troubles

I had the same problem with my Sem Cycle and the crank arm nut coming loose. I
would tighten it very tight and it would still loosen within 1/2 mile. When I
replaced the nut I looked at the old one and noticed that the scallops on the
nut surface were worn off. I have not had a problem with it now for 2 weeks (20
miles or so). This may help if the crank arm has not been damaged.


– Dirk Iwema Cincinnati, Ohio USA Internet: Dirk.Iwema@ae.ge.com

On Thu, 14 Sep 1995, David Winston wrote:

> I think the key thing to make of all this discussion is:
>
> 1. Unicycle wheels and cranks are essentially bicycle-grade items
>
> 2. Unicycling exerts significantly more stress on cranks/spokes/etc. than
> bicycling ever will
>
> Conclusion: we should be suprised that unicycles work as well as they do
> considering what we put them through!!!

I think we need to be more precise about these statements, and exactly what’s
mean’t by a ‘bicycle grade’ item.

I wouldn’t expect a 200q ‘mountain bike’ to last more than five minutes on some
of the downhills I do. That’s why my cheap mountain bike cost over 800q. Yet
unicyclists buy cheap steel frames and cheap steel rims, the kind what are found
on 100q bikes and then expect them to last.

‘bicycle grade’ equipment takes far more pounding on a bike than on a unicycle,
with the possible exception of cranks. Lets take it bit by bit:

20" rims: Go to a BMX shop, get a ‘Perigrine’ rim. They cost lots, because they
are designed to cope with fearless manics airing ten feet then decking out. 48
spoke too, for people who like doing kick-ups. 95 spoke versions are available.
Seriously. You can try to break them. You’ll break first.

26" rims: I’ve hit rocks at 40mph on my mtb, trashed the tyre, landed in a heap
in pain and found the rims undamaged. Mavic M231 rims cost ~25q here. Alloy,
light and much stronger than a steel rim. Changing from a steel to an alloy rim
is the biggest improvement you can make to a standard unicycle. Pedals: Again,
cheap plastic ones might cost 5q but they won’t last. Decent beartraps will cost
25q and last.

What I’m saying is that the products exist to make bombproof unicycles. But
it’ll cost you. However, trying to use cheap bicycle components will just result
in lots of broken cheap bicycle components. Unicycling is harsh (tho not as
harsh as mountain biking or BMXing) so there is a certain minimal level of
quality that you don’t want to go below.

This minimal level of quality (alloy rims, cotterless cranks, decent pedals)
results in a unicycle that’ll cost more to buy than the 95q machines that most
people sell. But, if you ride regularly, then you choice is to pay for that
minimum level, or spend even more time and money replacing half the components
on your machine.

Jez

Re: Harware troubles (fwd)

Forwarded message:
>From root Fri Sep 15 03:45:37 1995
Date: Fri, 15 Sep 1995 09:45:26 +0100 (BST) From: Jez <jpw24@hermes.cam.ac.uk>
X-Sender: jpw24@blue.csi.cam.ac.uk To: Bill Gilbertson
<wrg@unirsvl.rsvl.unisys.com> Subject: Re: Harware troubles In-Reply-To:
<9509142028.AA17280@unirsvl.rsvl.unisys.com> Message-Id:
<Pine.SUN.3.91.950915093716.10303A-100000@blue.csi.cam.ac.uk> Mime-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII

On Thu, 14 Sep 1995, Bill Gilbertson wrote:

> Thanks for the great info. I will go order Mavic or Peregrine rims tomorrow.
> Do spokes matter? e.g. Is there a difference in metal properties or simply a
> difference in gauge?

Get stainless steel. Galvanised steel is cheaper but weaker and look grotty.
Avoid at all costs. You may be offered aluminium nipples, stick with chrome
plated brass. Ally is lighter but tends to sieze onto the thread making wheel
trueing impossible.

If you want to be silly/spend lots of cash, you could try titanium spokes.
Lighter, strong enough but stupidly expensive.

As for sizes, I can never remember gauge number off hand, but ask for the same
thickness that they’d use for mtb. wheels. Double-butted spokes would save some
weight, but constant thickness spokes would be fine and cheaper. Make sure that
the bike shop has a good, experienced wheel builder, wheel life is definitely a
function of the skill of whoever built it.

Oh, and get a decent tyre. For 26", there are plenty of excellent 1.5" mountain
bike slicks, that are very light and can be pumped up hard (like 100psi) for low
wear, fast rolling and easy turning. For 20", try something like a Tioga Pool
Comp slick, probably only available from BMX shops.

Hope this helps

Jez.