Rear wheel with rotor brake substitute

Now were getting close to convergence Cam. In you're second to last paragraph the F=ma you refer to is correct and is the way I started to calculate the braking force required.
Mass of the bike&rider * acceleration, but deceleration in this case.
So, m*(-dv/dt), ie (velocity at start of braking - 0) / (time from braking to stop). The force of that moving bike is countered, equal and opposite, by the braking force. That is why I chose a worst-case scenario, trying to calculate that force, then calculate that back to the opposing force at the bracing bar. You are correct in saying, once the tyre looses traction, that is the point of maximum possible force. But we need to find a way to quantify that point. That was my wild ass guess by slamming just the rear brake on at 160km/hr.
(we better end the analysis soon, these pragmatic guys might throw us off the forum!😉)
 
Sorry, you guys can toss around as many numbers as you like, that set up still looks marginal and potentially dangerous to me. It is technically wrong on so many levels, it would fail race scrutineering, let alone a roadworthy check.

I've built championship-winning race bikes and only have an engineering degree, so, wtf do I know... :rolleyes:

piet
 
helicopterjim said:
Unless it's in the union ........ then it's working for you even if it doesn't work ........ and there's nothing you can do about it.

Jim
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You reminded me of a union strike of 5 days, I had to take part in, which gave us a pay rise of 20c per day, a dollar per week. And then the union patted itself on the back by increasing its dues greater than the pay increase!

Thanks to the union for that!
 
sfcpiet said:
Sorry, you guys can toss around as many numbers as you like, that set up still looks marginal and potentially dangerous to me. It is technically wrong on so many levels, it would fail race scrutineering, let alone a roadworthy check.

I've built championship-winning race bikes and only have an engineering degree, so, wtf do I know... :rolleyes:

piet
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Please don't take it personally Piet. I apologise if you feel offended, that was certainly not the intention. I was simply exchanging ideas with Cam, no criticism of your experience in any way.
I respect your opinions, but I don't necessarily agree.😉 Opinions and facts are different things, as of course you know.
(It could have been worse, we could have been discussing orange paint😄)
 
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sfcpiet said:
I'm not taking it personally Chuck, only well-meant advice. It's your skin and bones you're risking.

piet
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Appreciated Piet, thanks.
I felt the same way when I maintained and flew full-size gliders solo or rode the Honda 1300 on PI racetrack. A balance of risk-reward.
But to keep my bike insurance policy valid, I will have a licenced roadworthy inspector give it the once-over.
Chuck
 
So much for unsprung. Seen double on choppers funnily with no front brake. Three is new to me and monoblocks to boot. Obviously not real, I think?
 
sfcpiet said:
Sorry, you guys can toss around as many numbers as you like, that set up still looks marginal and potentially dangerous to me. It is technically wrong on so many levels, it would fail race scrutineering, let alone a roadworthy check.

I've built championship-winning race bikes and only have an engineering degree, so, wtf do I know... :rolleyes:

piet
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I actually agree with you Piet. It's not how I would have done it.
But I'm in the same boat as you with a crappy mechanical engineering degree that's worth nothing in today's corporate world of bankers on million dollar salaries and dodgy financial wheeler-dealers. I'm barely qualified to assemble Mecanno (is Mecanno still a thing, or is everything Lego these days?).
 
Bet there linked to a thumb left bar lever, how else do you stop looping out with the vertical wheelies at triple-digit speed.
 
Those things are presumably stunt bikes, to judge from the sprox.

I'm with Piet on the 3CL brake, but if the owner is happy then hey ho it's a free world.
(oh, actually, it's anything but a free world Australia since March last year...)
 
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