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Discussion Starter #1
http://www.reverserotatingrotors.com/


Neat and simple idea. Cancel most of the gyro forces of the front wheel.
The only disadvantages I can see right away are increased unsprung mass and increase cost/complexity.

Still very neat.
 

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It doesn't go into any detail on how this is achieved and the associate weight increase over conventional rotors.

Not too good for the track I would think. A sudden increase in gyroscopic forces as the rider brakes midcorner is just another handling issue for racers to contend with.

Still, good to see that some are thinking outside the square...
 

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Discussion Starter #3
Why a sudden increase?

I'm willing to bet the system uses several gears in a planetary arrangement inside the hub to spin the rotors the opposite direction of the wheel. The rotors will always spin in the opposite direction wether the brakes are applied or not. The gears will have to be strong enough to withstand braking forces. Additionally gear lash may play some interesting affects here.

Now, with different gear ratios it should be possible to spin the rotors fast enough to cancel the gyro forces of the front wheel entirely. I doubt anyone would do this, but if they were, I would think the bike would no longer countersteer. And then what?
 

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I can see ballance issues. Your bike remains upright under motion due to these gyroscopic forces. It will always return to upright position out of corners simply by relaxing your pull on the handlebars. If that effect is taken away, what you are left with, IMO, is the ballance of a bicycle at 3mph... with speeds in excess of 180MPH. I, for one, would rather fight the gyroscopic effect in the corners than to have to worry about the ballance ALL the time. I like releasing my grip on the handlebars to readjust my backpack or sit straight up going down hills from time to time.
 

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Vash said:

The rotors will always spin in the opposite direction wether the brakes are applied or not.
Once the brakes are applied (slowing the speed of the disc rotation) there would be a change (increase) in gyroscopic force.

This one's best left to the bmw engineers to sort out...
 

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Discussion Starter #6
Cammo said:
Once the brakes are applied (slowing the speed of the disc rotation) there would be a change (increase) in gyroscopic force.

No it wont. Gyroscopic force will always vary with the square of rpm. The only thing is with this system (if its dont like it think it is) you are also making negative percent gyro force. Assume wheel A makes X*mph gyro force. This same wheel is equiped with counter rotors, that have their gearing set to 75%X*mph. Now the wheel only makes 25%X*mph of the gyro force. The force produced still varies with the square of the speed, but its devided by 4 (In a perfect universe where this thing has 100% efficiency). This should answear both concerns. It is essentially the same thing as fitting wheels that are 4 time lighter.
Oh, one more possible issue. Set the power settings on this thing too high, and you risk overheating your brakes, requiring bigger rotors. Bigger rotors will further increase unsprung weight. And the whole system should have considerable rotational momentum, which should decrease the brakes efficiencies somewhat.
 

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When I see their prototype is in demand by fellow racers then I will realize they are in the right. Presently I do not feel this is the answer.

Still I will admit that I can be wrong. Like when they were sending the factory 'works" Matchless 500cc Scrambler they offered it with this & that. One I turned down was swinging arm rear suspension in preference to ridgid rear end.

I know this sounds crazy yet for anything like leaf spring rear end suspension, torsion bar rear end suspension, hub suspension or springer suspension they all twisted like a snake as you came out of the corners & turned up the wick.

By next year (being '50) we brought in a few of these scramblers with s/arm rear end suspension. In a race I was outdoing every one, but being just a Club event we had Senior with Expert racers & I noted this one Senior chap was coming down some parts almost as fast as I was.

After the race I borrowed his & realized it was easier to handle on the flat parts, same with uphill, some of the burms & ESPECIALLY coming downhill. So contacted the makers & they sent me the complete kit to make the change.

So yes that 2" of so called travel in the rear with the nick named "jam pots" made a big difference & from then on it was used on most bikes to even some yrs later one S/A rear end suspension was used on Observed Trials irons.
 

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Discussion Starter #11
If you understand the concept.....




You just saw a chance to new smiley didnt you jason?
 

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I am very interested in this concept. I am very interested in how it would work. Pics would be great. I am just wondering if the bike will feel less stable in the turns due to the reduction of gyroscopics. If they only reduce the gyroscopics by about 25% I imagine that it would help a ton.
 

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Discussion Starter #13


This is not a very helpfull image, but its the best I got.

My concern is still over the increase in unsprung weight. What good is a bike that is easier to lean over if it freaks out over a bump?
 

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Discussion Starter #14
Also, I imagine this would require the forks to be spaced wider apart, as the rotors will try to twist over the braking load from a single unbalanced gear. That means the bushings on which the ride around the axle will have to be longer (unless the wheel bushings can be drastically reduced).

I'm not sure what the impact of wider forks would be (well slightly less ground clearance, but I doubt thats the limiting factor)
 

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I got few questions: The natural progression of the front wheel and all the unsprung weight is what gives resistance to turning at high speed, which many of us deemed stability. So if there is a counter force to negate the front wheel gyroscpic progression such as this gizmo, it has no effect on the rear wheel? Does that mean if we remove the front wheel off the ground, like a wheelie, the bike turns noticeably faster? Because if the front tire stops spinning in mid-air, then what happens to gyroscopic force, is it cancelled? Theoretically, wouldn't it work similar way as the rotating rotors? Or is the front wheel needed on the ground to initiate a lean? I always though the bike was steered through the rear tire, and the front wheel just added the direction to where to turn. If the front is up, and the rear tire is slow to change direction, does that mean there's gyroscopic force working on the rear as well?
 

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Discussion Starter #18
The front tire initiaties a turn, the rear handles the corner exits.
Theoretically a bike could steer faster in a wheelie with the front wheel stop, except there is no steering head around which to countersteer. Pushing on the bar isnt going to do any good.
 

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Hi All-

Depending or not whether everyone here is an "early adopter" of new technology we will see how this develops. I tend to let the marketplace sort the winning ideas from the losing ones and then make my selections accordingly. I don't need to be the first kid on the block to own a new whatchmacallit gizmo.

~ Blue Jays ~
 

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Discussion Starter #20
I'm still skeptical. Their propaganda is sounding very defensive and sometimes obsurd, but I have to consider the fact that they might just know more then me.
Other questions include torsional loads (I can see the whole assembly buckling under extreme braking) and the increase in unsprung mass, by far my greatest concern.
 
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