Reverse Rotating Brake Rotors

[WINJA]

a better system would be to mount a inline four engine north south in the frame and have two banks driving a crank shaft one direction and two driving the a crank shaft in another direction....IE:two cranks would be far more benifitial than reverse direction rotors as it will have few down sides...

!

NAH JUST MAKE THE CRANK GO BACKWARDS SO THOSE FORCES ARE PARTLY CANCELLED BY THE WHEELS ,JUST LIKE ROSSIS BIKE , YES ITS LESS PRONE TO WHEELSTANDS

[Motu]

They are turning on the same plane as the rotation of the crank or some such techo talk....kinda like if you had axles and wheels like that too.....In MX there is a trade off between flywheel weight and turning,the heavier flywheel is harder to turn.Same on the flattrack,the XR750 has the advantage of a narrow crank,the old XS Yamaha's were hard to turn because of the wider crank.And Honda turned the CX around to a fore and aft twin.

[NordieBoy]

And I'm still not sure, who has The Word on bike steering, I always assumed it was gyroscopic precession, but I've been hearing stuff here and there about tyre reaction forces. I am teh confuzzled!

Tony Foale speaks The Word on bike steering.

[NordieBoy]

Still confused. How does a Moto Guzzi go around corners then? Or a BMW twin?

They go around corners?

Next you'll be telling me they can wheelie...

[WINJA]

Still confused. How does a Moto Guzzi go around corners then? Or a BMW twin?

IS THIS A PT ? IF IT IS YOU SHOULD HAVE INCLUDED THE Y2K IN YOUR QUESTION.
ALL BIKES (IN THEORY WITH THE SAME GROUND CLEARANCE)CAN GET TO THE SAME LEAN ANGLE, HOW FAST THEY GET TO THAT ANGLE IS ANOTHER QUESTION , A 600 CAN GET TO ITS SIDE FASTER THAN A 1000 OF THE SAME SPEC, THIS IS IMPORTANT WHEN THE NEXT EVENT IE THE CORNER THAT IS COMING AT YOU FASTER THAN YOU CAN GET THE BIKE TO LEAN OVER

[WINJA]

In MX there is a trade off between flywheel weight and turning,the heavier flywheel is harder to turn.

WOULD IT BE FAIR TO SAY THEN THAT THE HIGHER YOU CAN HAVE THE HANDLE BARS RELATIVE TO THE CRANK AXIS THE EASIER ITS IS TO TURN IN DUE TO EXTRA LEVERAGE?????? HHMMMMMM

[cowpoos]

NAH JUST MAKE THE CRANK GO BACKWARDS SO THOSE FORCES ARE PARTLY CANCELLED BY THE WHEELS ,JUST LIKE ROSSIS BIKE , YES ITS LESS PRONE TO WHEELSTANDS

well that is true...and probally the simplest thing that could be done

also mounting the engine upside down will make a bike easyier to turn...by moving the crank higher on the bike you reduce the effort required to turn the bike [less bar leverage needed] and I'm surprised some whizzz hasn't done that yet!

[Ixion]

They are turning on the same plane as the rotation of the crank or some such techo talk....kinda like if you had axles and wheels like that too.....In MX there is a trade off between flywheel weight and turning,the heavier flywheel is harder to turn.Same on the flattrack,the XR750 has the advantage of a narrow crank,the old XS Yamaha's were hard to turn because of the wider crank.And Honda turned the CX around to a fore and aft twin.

Yith, it is becos the Guzzi and BMW cranks are effectively very close to the centreline. Remember it is only when you LEAN a rotating mass that gyroscopic forces come into it. An across the frame crank, when you lean the bike you lean the crank. With a fore and aft crank when you lean the bike you simply twist the crank around its own axis. So the crank contributes little gyroscopy, either way.

[riffer]

Great answers guys. Rep to you all.

[T.I.E]

question, when the discussion of crank came into saying that if an engine runs at 10 revs it's harder to turn a corner? due to cranks size eg 1000's ahave bigger cranks the 600's? so if it's in first gear and the engines screaming i'm fucked and ill end up going straight ahead? even doing 70kph? and change into 2nd and revs drop so turning a piss of cake?

and with a counter rotating rotars, i'm interested if it would decrease the cyn-tri-fiya-cal oh shit the force, or would it increse it? the force maybe moving in the opposite direction but it is all based on a single spinning point with the same rotation. just a different direction.

oh my head hurts.

[Pixie]

While thinking about the Gnome-Rhone rotary radial aircraft engine.(the crank is stationary and the cylinders rotate)
I thought it would be good to have the calipers attached to the wheel and the disc fixed to the forks.
That's my silly idea for today.

[WINJA]

question, when the discussion of crank came into saying that if an engine runs at 10 revs it's harder to turn a corner? due to cranks size eg 1000's ahave bigger cranks the 600's? so if it's in first gear and the engines screaming i'm fucked and ill end up going straight ahead? even doing 70kph? and change into 2nd and revs drop so turning a piss of cake?

and with a counter rotating rotars, i'm interested if it would decrease the cyn-tri-fiya-cal oh shit the force, or would it increse it? the force maybe moving in the opposite direction but it is all based on a single spinning point with the same rotation. just a different direction.

oh my head hurts.

YOU WONT GO STRAIGHT AHEAD , BUT YOU WILL BACK OFF THE THROTTLE AND INCREASE THE TIME IT TAKES TO GET TO THE CORNER AS THE 1000 TAKES MORE TIME TO GET ONTO ITS SIDE.
EG ME AND ANOTHER HOON ARE ON OUR WAY TO PIHA IM ON MY GIXXER1000 WITH THE SAME GEOMETRY AND SAME WHEEL AND DISC ROTATING MASS AS HIS GIXXER 600 .GET TO THE FIRST LEFT HAND CORNER AND WE BOTH LEAN IN AND MAKE THE CORNER AT THE SAME SPEED , BUT IF TTHE NEXT CORNER IS A RIGHT AND THE TIME IT TAKES TO GET TO THAT CORNER IS SHORTER THAN THE TIME IT TAKES TO GET THE 1000 ONTO ITS RIGHT SIDE I WILL HAVE TO BACK OFF AND INCREASE THE TIME IT TAKES ME TO GET TO THE CORNER SO I DONT RUN WIDE, MEANWHILE THE FLICKABLE 600 HAS MAINTAINED ITS SPEED AND ALREADY GOT ONTO ITS SIDE READY FOR THE CORNER, AND HAS THEN GAPPED ME BY A FRACTION OF A SECOND, THROW A THIRD CORNER INTO IT AND THE GAP WILL BE GREATER

[Ixion]

While thinking about the Gnome-Rhone rotary radial aircraft engine.(the crank is stationary and the cylinders rotate)
I thought it would be good to have the calipers attached to the wheel and the disc fixed to the forks.
That's my silly idea for today.

Somebody did that. One problem is that the disc will have a heat gradient across it, cos the front will get more cooling than the rear, which may lead to distortion. Also be rather hard to arrange for the hydraulics .

[Ixion]

Mind you, some of the difference between the hypothetical 1000 and 600 may be due to engine width - more weight outboard in the bigger motor. The height of the CoM would come into it , too. And the bigger motor must have either bigger bore (wider) or longer stroke (higher) . I think.

[T.I.E]

YOU WONT GO STRAIGHT AHEAD , BUT YOU WILL BACK OFF THE THROTTLE AND INCREASE THE TIME IT TAKES TO GET TO THE CORNER AS THE 1000 TAKES MORE TIME TO GET ONTO ITS SIDE....

so is it more the weight of the bike due to it enertia or kenetic energy as it wants to go straight ahead as opposed to the crank, limiting it's turning ability?