Bill
Some years back Chet Herbert built a 4 wheel drive 4 engine streamliner and
used alum wheel/tire design
for the front dr. They were about 32" in dia and 8" wide with a almost flat
surface. They were like the flywheel as you state, vibrated because they
pack salt and was very hard to steer according to Don Vesco after a couple
of test passes.
They came back the next time with rubber bonneville tires and it made a big
differance in handling and did not pack salt on the tire. Enough tire flex
to not allow the salt to stick to them.
Glen
----- Original Message -----
From: <ardunbill@webtv.net>
Subject: Aluminum Front Wheel on MC Streamliner: Gyroscopic Effect at 300
MPH
> Hi folks, this is for the physicists and engineers in this forum, got a
> question that's beyond my capability.
>
> I previously told you that an interview with Dave Campos about his
> (existing) 1990 FIM World MC Speed Record(322.149 MPH) is just about to
> begin in Bonneville Racing News.
>
> Dave told me at the beginning of 1990, for lack of good fresh high-speed
> rubber tires, their team tried to use a 75 lb, 25" one piece aluminum
> front wheel. This was made in the form of a disc with a roundish
> cross-section rim on it. I would estimate that half of the total weight
> of the wheel was in the rim portion.
>
> This wheel was not successful, at first because the weight of it made it
> bounce over the bumps on the salt flats, and stay in the air too long at
> high speed(no steering then needless to say), but even more serious, the
> 'liner crashed with it at close to 300 mph, and they lost confidence in
> it; and reverted to a 500 x 15 rubber tire(only 15 pounds for wheel and
> tire) for the rest of their program.
>
> The question I have is about the amount of gyroscopic effect that this
> 75 lb aluminum wheel with its heavy rim would produce. I discussed this
> with Dave. It seems to me that such a wheel, spinning like a heavy
> flywheel at 300 mph, would build up a very sizeable gyroscopic force,
> possibly to the point that it would take a lot of force to get it to
> react to the rider's steering effort input. Because the heavy wheel
> would want to stay in its plane of rotation, and resist an attempt to
> change that plane.
>
> Can anyone compute the forces that would be involved here for us? Bill
> Hoddinott
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