Re: Zesdaagse van Amsterdam- Ewoud ?




"Ewoud Dronkert" <firstname@xxxxxxxxxxxxxxxxxxxx> wrote in message
news:kl3tm1566jg7haid5ubngac5325468lpir@xxxxxxxxxx
> Ryan Cousineau wrote:
> > Ewoud: what the heck is with those bikes? I recognize them as ordinary
> > Yamaha SRX, but why the weird handlebar extensions, rearset seating
> > position, and then a long roller standoff behind? I don't understand.
>
> http://www.pixagogo.com/9113945179
>

I believe the idea is to create a standard postion. Basically, the rear
subframe is modified, rearsets (after a fashion) attached, the seat is
angled at about a 30 degree downward angle (essentially to support in an aft
as much as lower aspect), and handlebar extensions to allow the driver to
stand upright while operating the motor. The roller extension is to limit
how closely the rider can draft the motor for safety reasons. The roller is
extended farther from the motor on smaller tracks to limit the speed the
riders can achieve/maintain.

I've never found motorpaced racing to be especially interesting, but then
again, the only motorpacing I've witnessed are the hour long races during
the Worlds. Passing occurs on a significantly decreased basis, and there is
no peloton to speak of (usually less than 10 rider/motor combos on the track
at a time, all spread out over the track). The interesting parts come when
one rider makes an attack and the rider ahead of him lifts his speed to
prevent it. Because the speeds are higher than unpaced riding, the passes
are more gradual. Occasionally you will see one driver twist his body in
order to angle the wind and direct it onto the other rider in an effort to
blow him off his motor. Usually one or two riders will go so hard that they
blow up and lose contact with their motor. The consequences of that are
dire, because it takes at least several laps for the rider/motor combo to
get together again. The motor driver often doesn't realize immediately when
the rider pops, and the rider, who is blown for the moment, cannot possibly
push the huge gear in order to keep up with the motor.

The nastiest motorpace crash I ever saw was during the '93 worlds when the
driver for Antonio Fanelli went high to pass another team and hit the
balustrade with the roller extension on the backstretch. He fishtailed and
lowsided the motor and Fanelli slammed into the back of them. There were
wood chips flying everywhere from the gouges on the track; it looked like a
lumberjack chainsaw championship on OLN. Amazingly, Fanelli only suffered
from abrasions (and probably enough splinters to start a campfire) and was
back on his bike an hour later when they did a restart.

Motorpace motorcycles are distinctly different than the derny that Magnus
Backstedt rode behind. A derny is like a moped on steroids (except the
engine isn't much bigger). It has a small two stroke engine (motorpaced
bikes are usually over 600 cc) and the driver sits on it conventionally. You
can pedal it, but the gear is massive, like a 100 tooth chainwheel, and the
gear is mainly to help keep the speed steady when the small motor drags
going into a headwind. There is no roller on a derny, only a rounded plastic
fender to prevent the bicycle's front wheel from contacting the derny's rear
wheel.

The UCI rules for motorpace motorcycles can be found here:

http://www.uci.ch/imgArchive/Rules/3trac-E.pdf

starting at 3.6.007 on the rulebook's page 50, pdf page 52


.



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