D
David L. Johnson
Guest
On Sat, 09 Apr 2005 02:26:26 +0000, Leo Lichtman wrote:
> Why are pedals threaded RH on the right side, and LH on the left side? If
> the idea is to keep the pedals from working loose as you ride, I think
> they've got it backwards.
No, they don't.
> The torque applied to the pedal shafts by the
> bearing friction, in the existing system, tends to loosen them.
No, it doesn't. You have to think about how the bearing balls move in the
system to see why.
> But that
> friction is so low compared to the tightness of a properly installed
> pedal that I don't think you could unscrew a pedal by spinning it.
It did happen. But this is ancient history, since all bikes have had the
pedals this way since the very early part of the 20th century (the idea
being introduced by the Wright brothers).
People who adapt single-bike cranks to tandems have trouble with pedals
unscrewing, since three of the 4 crank arms are the "wrong" side.
>
> What am I missing? They used to have left handed lug nuts on cars, and
> they don't do that anymore. Could bicycle technology be THAT far behind?
Lug nuts are different. However, a tapered fitting like a lug nut would
also work, as has occasionally been mentioned here.
--
David L. Johnson
__o | And though I have the gift of prophecy, and understand all
_`\(,_ | mysteries, and all knowledge; and though I have all faith, so
(_)/ (_) | that I could remove mountains, and have not charity, I am
nothing. [1 Corinth. 13:2]
> Why are pedals threaded RH on the right side, and LH on the left side? If
> the idea is to keep the pedals from working loose as you ride, I think
> they've got it backwards.
No, they don't.
> The torque applied to the pedal shafts by the
> bearing friction, in the existing system, tends to loosen them.
No, it doesn't. You have to think about how the bearing balls move in the
system to see why.
> But that
> friction is so low compared to the tightness of a properly installed
> pedal that I don't think you could unscrew a pedal by spinning it.
It did happen. But this is ancient history, since all bikes have had the
pedals this way since the very early part of the 20th century (the idea
being introduced by the Wright brothers).
People who adapt single-bike cranks to tandems have trouble with pedals
unscrewing, since three of the 4 crank arms are the "wrong" side.
>
> What am I missing? They used to have left handed lug nuts on cars, and
> they don't do that anymore. Could bicycle technology be THAT far behind?
Lug nuts are different. However, a tapered fitting like a lug nut would
also work, as has occasionally been mentioned here.
--
David L. Johnson
__o | And though I have the gift of prophecy, and understand all
_`\(,_ | mysteries, and all knowledge; and though I have all faith, so
(_)/ (_) | that I could remove mountains, and have not charity, I am
nothing. [1 Corinth. 13:2]