Thoughts on braking

In article ,
Luigi de Guzman wrote:

[front brake]

Then, out of curiosity, I went to see what our fossil-fueled brothers
on motorbikes have to say about braking. They say to brake with both
at the same time:

[quote from MSF]

1) Those big Flying Pigeons or Dutch roadsters, with only coaster
brakes, were probably never intended to go very fast at all. My
braking distance with only a rear coaster was scary, and my ability to
brake depended largely on where my feet were in the pedal stroke.
unnerving. [and I'm not very fast--the messengers and a lot of
commuters, indeed, at at least one little girl can all beat me,
speedwise]

Early motorcycles had only one brake, the rear, as well.


2) Is there some sort of maximum speed, or some other purely physical
limit to front-brake only braking?

Yes, the point at which you flip the bike over forwards.

Why do the motorcycle guys
recommend two-brake braking?

This is the MSF you are quoting. They are there to teach
beginning riders how to ride. Beginning riders, and riders who
learned improperly, are like your friend: they are afraid of
the front brake. There is even an old myth among motorcyclists
that the front brake will "flip you right over".
But on a motorcycle the front brake is
even more important than it is on a bicycle.

Motorcycle road racers often use only the front brake. Most of
those that use the rear use it more for suspension-related
reasons that are not applicable to bicycles and are too complicated
to explain.

A good motorcycle road racer will, at the point of maximum braking into
an approaching corner, have essentially zero weight on the rear.
Gary Nixon was famous for having his rear wheel in the air
on the approach to every corner.

3) If trail riders don't use their front brakes much--as my friend,
who was a sometime MTBer, seems to allege--why do I see so many
front-wheel disk brakes?

Your friend is wrong. Front brakes are important for
off-road riding as well.


Eric

Motorcycle road racers often use only the front brake. Most of
those that use the rear use it more for suspension-related
reasons that are not applicable to bicycles and are too complicated
to explain.

Not really. They use, as you say, the rear to lower the bike overall and
lower the CG. It's easy to visualize. Oftentimes (such as in MotoGP) it's
used AGAINST the throttle to control the amount of thrust.

--
Phil, Squid-in-Training