Standing
On The Pegs
Does NOT
Lower The Center Of Gravity
Apparently
somebody has posted a message on some news list that stimulated
quite a few e-mail messages to me seeking confirmation of another
bit of folklore that is pure rubbish. The claim is that if you
stand on your pegs you lower the bike's Center Of Gravity so that
you can have better control of it.
The
thought is that because you take weight off the seat and place it,
instead, on the pegs, that you have lowered the Center Of Gravity
as a result. Wrong! [Well, wrong if you STAND in order to do it.
If you merely put a bit more of your weight on the pegs while
remaining on the seat you will shift the Center of Gravity VERY
MODESTLY (insignificantly) down.]
Consider:
If the bike was at a dead stop and you were sitting in the saddle
all the weight would be distributed onto the contact patches of
your tires. That is, if the total weight of the bike (including
you) was 1,000 pounds, there would be about 600 pounds on the rear
tire and about 400 pounds on the front tire. Now, if you stood up
on the pegs and measured the weight on each tire you would find
the total remains at 1,000 pounds. However, it would probably be
closer to 550 pounds on the rear tire and 450 on the front. i.e.,
you have probably moved the CofG forward, but you have not reduced
it one ounce.
It
is clear that you DO change where the CofG is by standing on the
pegs. At least you now know that it typically moves foreward (at
least it does if the pegs are closer to the front of the bike than
where your butt usually rests on the seat.)
When
you sat on the seat you RAISED the combined CofG of the bike
(including you) as compared to where it was when you were not on
the bike at all.
Now,
as you stand on the pegs rather than sit on the seat, you RAISE
the combined CofG even further!
It
is true, however, that you increase your ability to quickly lean
the bike in this new posture, and you do not have to suffer the
shock (at least the indignity) of that seat slapping your butt
when the bike bounces over those railroad tracks.
This
is true because you have, when standing on the pegs, placed your
body torso on top of another set of 'springs' - your knees. Your
body is now 'double sprung weight' as a result. You have, in other
words, allowed your body to move in another direction than the
bike moves. (It should be clear that the body will follow the
average direction of travel of the bike, of course.)
For
those who still misunderstand, if you stand on your pegs as you
ride through a set of twisties you know, (I hope), that you will
have LESS CONTROL and could not negotiate those curves as fast as
you could if you were sitting in your saddle. This, because your
combined CofG is HIGHER. Your bike would have to lean farther than
it would if you were sitting in the seat to manage the same curves
at the same speed.
- Standing
on the pegs moves the combined CofG of your bike and you
FORWARD.
- Standing
on the pegs moves the combined CofG of your bike and you UP.
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