Re: stiff or flexible parts
unifoss@CERF.NET
Mon, 10 Oct 94 22:57:35 PDT
Ken Fuchs wrote:
>to plant the feet in certain skills and the flexible frame is a
>dubious advantage. (What Semcycle says about the flexible frame, may
>be true, but I don't think they have proven it, in any demonstrative
>way, such as a World Champion using it in his winning routine.)
>
>peterp@foe.co.uk (Peter Philip) wrote:
>
>>( Sem Trainer works on the 'stiff frame, flexible wheel' theory while
>>the Semcycle is 'stiff wheel, flexible frame' )
>
>I assume this is a quote from Semcycle, either written or verbal.
>
>A stiff wheel and flexible frame sounds like a functional arrangement
>that may even lead to a superior product.
>
>Concerning the 'stiff frame, flexible wheel' theory: How can one have
>a flexible wheel, without loose spokes? This question should really
>be directed to Semcycle. Would someone please post an explanation. I
>get this image of Semcycle telling people to keep their spokes
>slightly loose on the LX, so the wheel remains flexible. How can the
>wheel be kept true without tight spokes? Slightly loose spokes will become
>looser since there not enough force is applied to the nipple to keep
>it from turning. They do use normal rims, spokes, nipples and hubs
>for the LX, don't they? Just how do they make the wheels flexible?
>
I believe what Semcycle is trying to say is that a cross-3 or cross-4 spoke
pattern will make for a wheel that is more flexible than a cross-1 pattern.
The higher cross numbers will give the wheel a bit more "spring." They also
give the wheel a bit more strength, which is why almost all normal bicycle
wheels have a cross 3 or 4 spoke pattern.
When I personally think of a flexible wheel, I think of the sound and flex
motion of an old style Semcycle wheel with radial spokes. If the spokes were
loose, you could hear it coming a block away. The solution to this problem
was to tighten the spokes weekly. I prefer the wheels I use, which only need
to be tightened once or twice a year.
Why does one want a flexible frame? For freestyle, I would tend to want a
rigid frame that would give me predictable responses. A Semcycle split-fork
frame flexes left to right. In other words, the saddle can twist left and
right, which may actually cut down on leg friction against the saddle on long
rides. For any kind of trick riding, though, give me a rigid frame.
When looking for a new unicycle, I recommend a rigid frame, and a saddle with
plastic bumpers if you can find it. The Semcycle XL has both.
John Foss, President
International Unicycling Federation
unifoss@cerfnet.com
voice: (516)731-7613