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Crap concept or sheer genius?

Discussion in 'Technical and Troubleshooting Torque' at netrider.net.au started by Gromit, Apr 5, 2006.

  1. http://www.reverserotatingrotors.com/

    Okay, tech-heads - would this work as advertised? I smell the distinctive whiff of snake oil, but I'll leave it to others to judge...

  2. I'd work as advertised. no question, just year 11 physics.

    The catch as i can percieve it is having a disc explode because it has to spin backwards MUCH faster than the wheel is spinning forward to cancel the gyration of the wheel (because it's small and light)

    Someone who knows better than me might be able to suggest if a disc is actually likely to blow up, or if it's fine to spin them at 10x normal speed.
  3. I imagine you'd be increasing the unsprung weight, which isn't ideal.
  4. It looks like the sun gear is part of the axle, the planetary carrier is fixed to the fork leg which allows the planetary gears to rotate in a fixed position, causing the annulus to spin in the opposite direction.
    I can't see the benefits outweighing the drawbacks.
  5. Certainly could use less gyroscopic effort to fight directional changes around PI. The ~200kph transition from mid-high lean left to full lean right between Turns 7 & 8 requires me to use both arms to wrench the bike over.
  6. I think it is a great concept. I'd like to see how well the where and tear of it all holds up or whether a cog or cog tooth could break loose inside the assembly and cause a front wheel lock.

    If all the checks out then i'd give it a go. I reckon it looks trick aswell. Just something about the brake rotor rotating backwards compared with the wheel looks awesome!!!
  7. Don't forget to factor in accelerated pad wear. Different compounds would be needed to suit this system.

    I don't like them, better to keep things simple. I don't see how when the brakes are applied (and the counter-rotating disc speed is slowed) that gyroscopic forces don't increase, unsettling the bike. And yes, there would be an increase in unsprung weight.

    Mor of a gimmick IMO, this info has been around for a while, and I've yet to see any good unbiased reports/tests.

    Most of the better developments are in some way derived from motorsport, I doubt Rossi and Co will endorse them...
  8. Wouldn't that be because when the brakes are applied the wheel is slowing down at the same rate as the disc rotor, therefore the gyroscopic effect should remain at the same ratio (but not same effect as the bike is slowing down so the effect will be less pronounced)??

    Extra weight = extra rotational mass

    extra rotational mass = increase in wheel inertia

    increased inertia = more pronounced gyroscopic effect by the front wheel thus making the bike harder to turn.

    THEREFORE shouldn't the fact that the system is supposed to dramatically reduce the gyroscopic effect negate the fact that there is a slight increase in unsprung weight? The small increase in weight shouldn't be a problem because if it works as claimed the fact the bike handles quicker and stops easier should mean the extra weight isn't an issue.
  9. I don't understand why pad wear would be increased.
    I would also think that the idea of counter-rotation is so that the gyroscopic forces cancel each other out, to a limited extent; depending on the mass of the rotor. I would think that a bit of thought put into the size of the swept area and the hydraulics would overcome any loss of braking power due to slower rotor speed. But I agree, seems to be an unnecessary complication.
  10. I'd be keen to try it to see if the feel and handling was worth it. I'm not concerned about the extra weight, after all the poor bikes have haul our not-so-athletic bums around.

    I'd like to see a track test by a reputable racer for the real verdict though.
  11. I'll get it when MotoGP and WSBK use it...
  12. I'd liken it to power steering. Heavy and complicated, but still nice to have.
  13. The gyroscopic force is what rights the bike out of a corner, it is what makes it easy to ballance at speed, contering this (Especially for a beginer) would make it seriosly harder to ride. It may have a role for race bikes, but I personaly think for the rest of us it would just be a hinderance.
    BTW It is a re-post https://netrider.net.au/forums/viewtopic.php?t=16165
  14. A repost? D'Oh!!!

    (Sorry, guys...)
  15. i personally think it's a bit impratical and i suspect it wouldnt have any advantage over steep steering geometry and a good steering damper...

    (and in case anyone didn't know, just because a patent exists doesnt mean it is working/useful/valuable)
  16. gyroscopic precession acts normal to the plane of rotation as has been said before - doesn't matter what direction things are spinning - the gyro tries to oppose the motion placed upon it.

    physics calls bullshit.
  17. wouldn't this make it alot more touchy at faster speeds, which would be worse :\
  18. As far as I understand it its the rear wheel's gyroscopic forces that provide the bulk of the bikes stability and front wheel is there to distablise the bike so you can go around corners.
  19. The last bit of the video with Rossi is funny as. :grin:

    That'll teach him to do wheelies.