Somebody recently opined:
>On knock offs, in addition to the rear wheel torque (on acceleration)
>tightening knockoffs when they are on correctly, rolling resistance
>should in general tighten both the rear and front wheels. I have not
>read this authoratatively, but as I sit and think about it, I believe it.
>Just think that the wheels really don't want to turn as fast as the hub,
>even when they are just rolling - due to friction with the road and (hopefully
>very little) with the hub bearings. . . .
Well, no, I don't think that's quite right yet. When cruising down
the Interstate, bored out of our minds, the rear hubs drive the rear
wheels, but the front wheels drive the front hubs, making them turn
against the drag of the bearings. So the torque is working in
opposite directions between front and rear.
Nobody has addressed the question of braking, when the torque loading
in the rear hubs reverses (but it seems to me like the direction of
the load in the front hubs stays the same, but increases drastically,
as the drag from the brakes is added to the drag from the bearings.
A mental experiment: take a Triumph or Healey with splined hubs and
the usual knockoffs - left hand threads on the right hand side of
the car (please Lord, let me have that correct). Now suppose that
the wheels were make by J. Lucas and Co., so the splines suddenly
disappear and the wheels become free to rotate on the hubs. Under
acceleration, the rear hub spins, the wheel stays still, and the
knockoff tightens. Hurray for our side! But as the car starts to
move forward, the front wheel is forced to turn, but the front hub
would just as soon stay still, so the front knockoff unwinds and
falls off. Bummer! Consider cruising along steady state, then
applying the binders. Both hubs want to stop turning, while the
wheels want to continue. All the knockoffs fall off. BUMMER!
So. What's going on here? Is my experiment full of brown ale?
The situation looks like a loser three out of four times. I'll
admit I don't completely understand the situation, but just
what IS the rationale for the threads on knockoffs? Life is
one mystery after another, especially when sworking on LBCs.
Jim Beckman att!mtqua!jeb A-H 100
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