Vented Discs

On Jun 25, 4:59 pm, Andre Jute wrote:
snip
I have seen bicycles that set their brakes on fire stopping after a
straight line run on level ground, at Battle Mountain NV.

I'll leave that one to the local scoffjaws, who're just engaging motor-
drive.

These were human powered bikes capable of 80km/h for an hour and
sprints in excess of 110 km/h, not assist bikes.

I have
personally experienced tire failure due to brake heat riding down Big
Cottonwood Canyon east of SLC UT.

Why don't you tell us how long and steep this ride is, how
irresponsibly you rode down there, how the tire failed, how you
determined that it was due to brake heat. Note that I never said it is
impossible, merely that the circumstances are rare and avoidable.


I don't have the info on that ride, and from what I have seen on
Google the road has been changed considerably since I did the race
with my friends. The tire exploded off the rim when the bead melted
and caused the tire to escape the rim. I was riding steel rims with
centerpull calipers in the mid 1970s and the tires were rated to 95
PSI. We would ride our bikes to the ski resort at the top of the
canyon, recover and then race to Wasatch Boulevard at the bottom of
the canyon. There used to be a C-store there and whoever got to the
door of the C-store first was the winner, bike had to be upright on
the kickstand so you couldn't just ride up to the door you had to stop
and park the bike like a normal person who had just exceeded the
national speed limit on a 10 speed bicycle. Nobody had tires go down
on the runs, just in the parking lot at the C-store, and sometimes
they would fail spectacularly, as in flip the bike over and set it
back upright on the seat and handlebars. When the tubes were replaced
after the blowouts the tire almost every time would not seat the bead
because of bead damage. Sometimes the damage was so easily spotted we
didn't even try to reinstall it we just bought another tire.

Now we crashed a whole bunch of different ways, but we never had a
tire let go from the rim on the road. I had some scary moments on that
bike with the steel rims in the rain, but never had a problem in the
dry. That race down Big Cottonwood Canyon would wear out a new set of
pads if you didn't save your brakes by sitting up with your hands on
top of the bars before the turns