Questionable logic behind the...

[Anonymous]

technology of this guy:

http://www.reverserotatingrotors.com

Ive been thinking about it, and im not too sure. I personally think, with my understanding that this is a bad idea.

Discuss?

:?

[Supervox]

Weren't one of the race teams (I forget whether it was WSB / BSB / MotoGp etc) playing around with this idea a year or so ago ??

[Anonymous]

Weren't one of the race teams (I forget whether it was WSB / BSB / MotoGp etc) playing around with this idea a year or so ago ??

Im not sure, but someone from another forum said that if this technology was patented and worked.. surely a race team would be using it by now? :?

[tomjones2]

I may be being stupid but how does the weight of the rotors counteract the weight of the wheel and tire, woundn't the new hub add loads of unsprung weight as well?

[jonboy]

It doesn't counteract weight rather considerably reduces the gyroscopic effect produced by the wheel spinning, from what I can gather. If you've ever held a spinning gyroscope in your hand and then tried to move it quickly you'll have an idea of the forces involved. Now whether it works in the real world, who knows?


.

[Grinch]

huh? are they saying they have a wheel in the wheel spinning in the other direction?
Or they have a Gyro in the wheel?

[timwilky]

The idea seems to make sense. It looks like they use an epicyclic gearing to reverse the direction of the brake discs and by spinning them faster than the wheel rotation then "balance" the gyroscopic effects of turning a rotating disc.

I remember playing with gyroscopic effects on my mech eng degree 25 years ago. interesting then but well and truely forgotten about.

Out of interest if you have an old push bike wheel available, get hold of it with both hands holding the axle and get somebody to spin it. Now if you attempt to twist it, ie pull back with one hand and push with the other whilst holding it out in front of you the wheel will try to bank over. Similarly try to incline the wheel from the vertical and it will attempt to turn. It is these effects that this design is trying to counter.

I am however, not sure that you would want to mess to much with this, as there are other forces involved with cornering. What does concern me with this design is the fact that all the braking force will be transmitted back through the teeth of the epicyclic box. OK it looks like there are only 4 planetary gears. I have in the past seen epicyclic boxes that have failed under very heavy load. (Bus where the driver went through the gate mechanism and managed to engage reverse whilst the bus was still moving forward), once the teeth shear, your brake discs would simply rotate, and total loss of front brakes would occur.

[The Basket]

That website shows some nasty tankslappers...ouch.
Including that one from the IoM. And some geezer wheelie going wrong.

The IoM guy lost a few fingers and toes if memory serves...and that was lucky!!!

[skidmarx]

What a nutcase. No idea if the contrarotation would actually counteract the moment of inertia created whilst displacing said rotating mass about its axis. But the thought of loosing all that stability as your hurtling down the M1 in a cross wind sounds frankly terrifying!

[huge]

Interesting idea. No idea if it works.

Certainly Yamaha (I think Kawa as well) have been using contra rotating cranks and balance shafts in their current moto gp bikes to counteract the gyroscopic effect of the wheels.

I think we would all agree this works!!!

[jonboy]

Certainly Yamaha (I think Kawa as well) have been using contra rotating cranks and balance shafts in their current moto gp bikes to counteract the gyroscopic effect of the wheels.

Surely it's to counteract the gyro effect of the crank itself?


.

[Halonic]

it effectively gives you "weightless" wheels

the counteracting acceleration should reduce gravity due to acceleration depending on the rate of spin and mass of the discs.

Its all a-level mechanics but suffice to say acceleration in one direction added to acceleration in other direction means no net force, which in this case is the weight of the wheel (gravity), which is a product of mass and acceleration (newtons second law)

now as the brake discs arent equal to the weight of the wheel, it only gives you a reduction in weight, not a cancelation of weight, but it does roughly mean that the faster you travel (and the higher the rotation and therefore accelerating force of the wheel around the hub) the "lighter" the wheels will feel, hence the claim that it should be as manouverable at 20mph as it is at 80mph.

kinda cool really

[Flamin_Squirrel]

it effectively gives you "weightless" wheels

the counteracting acceleration should reduce gravity due to acceleration depending on the rate of spin and mass of the discs.

Its all a-level mechanics but suffice to say acceleration in one direction added to acceleration in other direction means no net force, which in this case is the weight of the wheel (gravity), which is a product of mass and acceleration (newtons second law)

now as the brake discs arent equal to the weight of the wheel, it only gives you a reduction in weight, not a cancelation of weight, but it does roughly mean that the faster you travel (and the higher the rotation and therefore accelerating force of the wheel around the hub) the "lighter" the wheels will feel, hence the claim that it should be as manouverable at 20mph as it is at 80mph.

kinda cool really

I suggest you go back and study A-level mechanics :lol:

It's got nothing to do with the weight of the wheel, all to do with the gyroscopic effects of a rotating mass.

[Peter Henry]

This is indeed an interesting theory. However my question would be....how tight a bend do you want to negotiate at 180mph? :shock: :?

[Anonymous]

This is indeed an interesting theory. However my question would be....how tight a bend do you want to negotiate at 180mph? :shock: :?

Something nice and sharpe.. perhaps a tight 90 degree'er. :shock: :lol: :lol:

[Peter Henry]

GYKD wrote:

Something nice and sharpe.. perhaps a tight 90 degree'er.

Joe...You don't mind if I borrow your bike when I try it do you? :lol:

[Flamin_Squirrel]

This is indeed an interesting theory. However my question would be....how tight a bend do you want to negotiate at 180mph? :shock: :?

I'm more interested in the tank slap elimination 8)

[Anonymous]

GYKD wrote:

Something nice and sharpe.. perhaps a tight 90 degree'er.

Joe...You don't mind if I borrow your bike when I try it do you? :lol:

Not at all buddy.. Its a 1989 G plate ZXR400 in a pile of bits in a mates shed. Bout £1k will do it up to a decent standard.... you pay for the repairs.. you can test out the theory.... :wink: :lol: :lol: