Re: Brakes? How?
>> In other words one’s legs get tired when racing. The same
>> muscle groups that are used in touring and also used in racing,
John Foss <john_foss@asinet.com> wrote:
>Muscle groups, yes. Specific areas of those muscles, no. You are not just
>working the same muscles harder. the effort is applied differently, not just
>the same thing faster. If you simply speeded up the pedaling motion of
>normal riding, your feet would flop all over the place. You have to add
>additional effort to keep them attached to the pedals. If not anything
>else, surely the increase of centripetal (centrifugal?) force means
>something to you.
Yes, of course one would have to practice racing to have a reasonable
chance of winning. I assume John is speaking from personal experience
rather than objective physiological data. The muscle groups are being
used faster and as a consequence more concentration and training is
required to control them, but is the movement really different, other
than being faster?
>> Pedal stroke variation is the minor adjustments to maintain forward /
>> backward balance. Pedal stroke variation is not starting or stopping.
>As the riding surface gets steeper and steeper, these two things get closer
>to being one in the same. On a short downhill, it’s possible to “roll out”
>and let the unicycle pick up lots of speed, as long as this happens near the
>bottom. Riding uphill is a better example. You’re going slow. You are
>pedaling in “steps,” where you lunge forward and pedal a half revolution,
>then pause to let your body get out in front of the wheel again. When it’s
>real steep, you have to do it this way because we are not electric motors.
>Each time you do a lunge, it has to be smooth enough to keep the wheel from
>losing its grip on the ground (picturing dirt again). So you are combining
>the adjustments to maintain balance with a pedal stroke variation that
>approaches starting and stopping. In uphill situations especially, if this
>happens it’s usually a near-instant dismount, so you must avoid it.
>So you’re not trying to start/stop, but if the trail is really, really
>steep, it gets similar to doing that.
OK, I understand the point you are making, but I wouldn’t be calling it
pedal stroke variation as the word variation usually implies small
changes when used in the context of amplitude. Not the changes required
to start or stop.
>Sure the whole trail isn’t this steep, but the less-steep stuff just isn’t
>that challenging, is it?
Sorry, I wasn’t considering hills that are too steep to ride up or down,
only those that would be challenging (not those that are nearly
impossible) to ride up or down.
>> You are confusing the tractional forces which are generated by the
>> resistance of ground with the forces that oppose traction which are
>> generated by the rider. These forces must be below
>Not confusing. When you’re out riding, it’s all the same. Tire grips, tire
>stops gripping. In most cases it stops gripping due to non-smooth movements
>made by the rider. Though it is possible to “power slide,” meaning to skid
>downhill for instance, you cannot consider yourself back “in control” until
>your wheel is no longer sliding. Or at least until you are deriving some
>degree of control from it, such as when riding down giant sand dunes on Long
>Island’s north shore.
Sorry, I didn’t complete my thoughts on this subtopic. I’ve done so in
amother post.
Control can be maintained with a sliding wheel. It is probably even
easier than coasting. I’d say that anyone who can glide, can maintain
control sliding the wheel over the riding surface. However, I’d not
aware of any experts at this skill. Who has done this? Probably very
few, because there are more fun and productive things to do on one wheel.
I can understand that you do not think that a more rigorous
understanding of physics can help you ride muni better, but it certainly
can.
>> I’d be. It’s braking system is controlled with perhaps a
>> reaction time
>> of 1 millisecond or better. A human unicyclist may have a
>> reaction time
>> of about one half a second plus limited power output for
>> nearly one half of every full cycle.
>It’s the pedal stroke that makes our lives difficult. The limited power
>stroke, and the fact that we can’t coast, are two of the factors that make
>MUni interesting. So what if the Segway beats us. It is, in effect,
>cheating. At least it won’t gloat at us when it gets to the top of the
>hill…
The point is that a machine could be built that balances on one wheel
and it could easily improve in balance and ride where no human unicycle
rider would dare go.
I don’t understand what is meant by “we can’t coast”, when a significant
number of unicyclists can coast.
>> We have to have both race results and rider weights for useful data.
>> Having the first and not having the second, still means we have NO
>> useful data.
>Essentially correct, though it one could get rough numbers from looking at
>pictures or video. You would have to know not only tire size and model, but
>also tire pressure (a little hard to get from the pictures), but at least
>you can estimate which riders are heavier than others…
Clearly not objective measurement.
>> How far behind me were you when I reached the finish line of the Great
>> Wall of China Unicycle Marathon (down and then up the mountain)?
>Far. Yes, Ken has beat me in a race or two, of which that one is probably
>the most notable, and definitely the most memorable. Kato was first, Ken
>second, me third.
>This should remind us that the most important factor in a race of this
>nature is almost always the engine, not the machine. Ken was in much better
>physical shape for long rides on small wheels than I was.
Thanks for the compliment!
>> The night before, I drank far too much snake schnapps and had a rude
>> hangover the day of the race. Many of the racers probably
>> did and maybe didn’t get enough sleep either. Maybe, we should
>> measure the affects of hangovers and sleep deficent on racing
>> performance.
>Don’t ask about the snake schnapps. Something I didn’t see served anywhere
>at UNICON X. Suffice it to say it was made from a snake that was alive when
>we entered the restaurant.
The snake schnapps was also very high in alcohol content. I’d like to
think that it was the alcohol content that had the most effect on me the
following day.
>I have also competed (and done well) after a severe lack of sleep. I don’t
>have the experience with hangover however. My most notable example of this
>was the marathon race at UNICON IV. It started early in the morning after an
>extremely late-starting IUF meeting that ran until 3:00am or so. I did not
>get to sleep until after 4:00. But somehow I came in third in the race,
>having even passed 100 miler Floyd Beattie. Again, my training (that year)
>must have been superior.
Thank you John for a very interesting discussion. You don’t need to
comment on this thread further on my account.
Sincerely,
Ken Fuchs <kfuchs@winternet.com>