Probability and consequence of slipping

Ivar Hesselager said:

I am preparing for the Oetztahler Radmarathon in Tyrol in late August and
will prepare my bike and myself for the possibility of having to ride down
the Alps in the cold rain. I could use some advice from exprienced mountain
riders or bicycle scientists. I have planned to bring with me, as a spare
tire, one Conti GP 4 Seasons, which is supposed to have a much better grip
in cold and rainy weather than the GP 3000, that I normally use.
Now granted, that I have only one GP 4 Seasons tire with me, where should I
mount the tire with the better grip: Front or rear?

I am not attempting any speed record, just want to make it through wihtin
the time limit. But I am rather old and heavy for the climbing of 5.500 m
during the day. So I could can sure use the weiht advantage going downhill -
without having to ride too "courageously".

My consideration - not based on experience - is that though front as well as
back wheel can slip - it does not have the same probability and not the same
consequence.

Back wheel slip is more probable (I routinely brake the back wheel first)

This is not the best procedure. For most conditions, you're better off
using the front brake by itself.

See: http://sheldonbrown.com/brakturn

Quoted message said:

Back wheel slip during braking can be saved by releasing the brake quickly
(my experience)

Front wheel carries the bigger part of the load on steep downhill turns

Front wheel slip will more often result in a fall

Front wheel slip will make a quicker and harder fall

Yes. If you will be using two tires with different traction qualities,
the one with better traction always should be on the front wheel

Sheldon "One Brake At A Time" Brown
+-----------------------------------------------------------+
| It is by riding a bicycle that you learn the contours |
| of a country best, since you have to sweat up the hills |
| and coast down them. |
| Thus you remember them as they actually are, while in a |
| motor car only a high hill impresses you, and you have |
| no such accurate remembrance of country you have driven |
| through as you gain by riding a bicycle. |
| -- Ernest Hemingway, By-Line |
+-----------------------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

"Sheldon Brown" wrote:
For most conditions, you're better off

Quoted message said:

using the front brake by itself.

I have read the well argued articles about breaking techniques by Sheldon
Brown and Jobst Brandt - and though I am impressed with their detailed
insight, I feel confirmed that braking rear wheel first is a good habbit.
I am convinced though, that the habit in my case originates from the
aparantly worldwide myth (which was prevailing wisdom in the 80's) that
braking frontwheel first, is likely to throw you head on over the handlebar.

I am sure Brown&Brandt are right, that in most cases it is unnesseray to
brake back wheel first. But it follows from that, that it IS necessary in
some other situations - when front wheel traction is low, or - and this is
important - lower than you expect.

It is logical, that you don't know when the traction is lower than you
expect, so you don't (allways) know when you should brake back wheel first.
And since in worst case it is unnecesary but harmless to brake back wheel
first, and in other cases - that you can't predict - it is necesary to
brake backwheel first, you are in my opinion still better off making it a
habit to brake back wheel first.

Roads in my part of the world get slippery from traffic film, rain, sand,
fallen leaves, ice etc. And a back wheel slide , which can be recovered,
can be considered as an early warning much preferable to a frontwheel slide,
that will probably bring you down. Furthermore the (limited) deceleration
of the back wheel braking, may just be sufficient to prevent the front wheel
from sliding when the front brake is applied.
So braking backwheel a split second before frontwheel is still the safer
procedure - and a good habit.

Thanks Sheldon for your brief and precise stating, that the tire with the
better traction goes on the frontwheel. No further explanation is needed.

Ivar of Denmark

------------------------------------

The word is round (I think Christobal Columbus said that)

The bike will get you aorund (I said that)

Quoted message said:

See: http://sheldonbrown.com/brakturn

Quoted message said:

Back wheel slip during braking can be saved by releasing the brake

quickly

Quoted message said:

Quoted message said:

(my experience)

Front wheel carries the bigger part of the load on steep downhill turns

Front wheel slip will more often result in a fall

Front wheel slip will make a quicker and harder fall

Yes. If you will be using two tires with different traction qualities,
the one with better traction always should be on the front wheel

Sheldon "One Brake At A Time" Brown
+-----------------------------------------------------------+
| It is by riding a bicycle that you learn the contours |
| of a country best, since you have to sweat up the hills |
| and coast down them. |
| Thus you remember them as they actually are, while in a |
| motor car only a high hill impresses you, and you have |
| no such accurate remembrance of country you have driven |
| through as you gain by riding a bicycle. |
| -- Ernest Hemingway, By-Line |
+-----------------------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com