Post by John RethorstPost by choro-nikHey, hey! Wait a moment there. Have you ever tightened normal screws? Yes,
they are all tightened clockwise. How come you claim you wind or tighten in
the same direction but then you say clockwise for one side and
anti-clockwise for the other side? Doesn't make sense.
Worked on British cars lately? Or maybe I'm dating myself, but screws used to
turn one way on one side of the car, the other way on the other side. Something
about them being less likely to work loose.
The best example of this I know of comes from the world of bicycles.
Back in the day, the "bottom bracket" on a bicycle (hereafter referred
to as the BB) had "cups" that screwed into threads on the bottom of the
bicycle. The BB is the entire business, axle, bearing, retaining cups,
seals, and the like, that the cranks attach to - you get a bare frame,
you install a BB, you install cranks, you attach pedals to the cranks.
(Yes, not all bicycles work this way, I know, but the majority still
do.)
Besides issues of threading differences, several different versions
existed in terms of normal or "left-handed" threads for each side of the
bicycle. In practice, only those with a reverse thread on one side and
a normal threading on the other stay in place over time.
Pedal holes are threaded reversed on one side of the bike for the same
reason - they tend to work loose if they are not. Why it works this way
is beyond my ability to understand or explain but it certainly does work
this way. You can, e.g., ride a bicycle after having only slightly
tightened the pedals in most cases because the pedaling motion will tend
to tighten, not loosen, them..
I know pedals are reverse threaded on the left (non-drive) side of a
bike, but it's been long enough that I don't remember if the BB is
left-hand threaded on the drive side or the non-drive side - ah, here we
go, a good link for us old pedallers who forget these things - it works
the opposite way on the BB than it does on the pedals:
http://www.sheldonbrown.com/gloss_bo-z.html#bottom
Steve "ah, but I digress" Freides