Rotors floating or solid?
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i do not think so.
think about it, the master cylinder & caliper would be smoking hot and the brake fluid going dark, not dark as in moisture being present.
maybe not so on a mc but floating rotors are often of less mass, aka, less heat retainment. throw in ventilation holes, grooves or whatever heat dissipation is fairly quick to the surrounding air.
i ride pretty aggressive and never experienced any issues even with over 120mph stops (speedo quits after this), the sport has stock dual disks on the front. even my 1974ch with crappy brakes does not have issues. in order to build up that much heat you would need a dragging brake or on the brakes all the time, personally, i am on the throttle way more especially so with the sport.
think about it, the master cylinder & caliper would be smoking hot and the brake fluid going dark, not dark as in moisture being present.
maybe not so on a mc but floating rotors are often of less mass, aka, less heat retainment. throw in ventilation holes, grooves or whatever heat dissipation is fairly quick to the surrounding air.
i ride pretty aggressive and never experienced any issues even with over 120mph stops (speedo quits after this), the sport has stock dual disks on the front. even my 1974ch with crappy brakes does not have issues. in order to build up that much heat you would need a dragging brake or on the brakes all the time, personally, i am on the throttle way more especially so with the sport.
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From: poway
be careful what you buy as not all so called rotors are floating. heat issue on a street machine is not an issue as mr. max pointed out.
there are several types of retainment anchor points being circular, flat and triangular.
rotors with circular retainment do not float. if it could, large amounts of space is needed and then the rotor would rattle. second , heat expansion has a tendency to wedge against retainer.
the other types allow for movement with out the need for excessive clearance.
axial floating rotor is doomed for failure and can cause braking issues with feedback(knock-back of the pads) into the controls and shortened component life, zero axial float is best.
the only advantage of a floating rotor is that it allows for movement to more fully conform to the pads, more conformity, better braking. really needed for a street machine, well, hummm, your dollar. all other things equal, the heat load would be nearly the same with a slight edge going to the floating rotor generating more heat, remember better conformity.
there are several types of retainment anchor points being circular, flat and triangular.
rotors with circular retainment do not float. if it could, large amounts of space is needed and then the rotor would rattle. second , heat expansion has a tendency to wedge against retainer.
the other types allow for movement with out the need for excessive clearance.
axial floating rotor is doomed for failure and can cause braking issues with feedback(knock-back of the pads) into the controls and shortened component life, zero axial float is best.
the only advantage of a floating rotor is that it allows for movement to more fully conform to the pads, more conformity, better braking. really needed for a street machine, well, hummm, your dollar. all other things equal, the heat load would be nearly the same with a slight edge going to the floating rotor generating more heat, remember better conformity.
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From: poway
The oil turning dark in the caliper leg over the other is a neat observation but I doubt it's due to heat from the caliper. Most oils don't start to oxidize until something above or around 250F.. Ever seen a set of forks get that hot? I would bet that the reason the oil turns darker on the caliper side due to the additional forces added to the fork leg when braking. The bushings see more load / wear.
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From: Nunya.
The oil turning dark in the caliper leg over the other is a neat observation but I doubt it's due to heat from the caliper. Most oils don't start to oxidize until something above or around 250F.. Ever seen a set of forks get that hot? I would bet that the reason the oil turns darker on the caliper side due to the additional forces added to the fork leg when braking. The bushings see more load / wear.
Just a comment no real right or wrong thing , an observation . Spose someone could test the oil ? See what gives.
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From: poway
It's just been an observation over decades of bikes , I've had more fork seals go on the side with disc brakes too , it might act on the bronze slider bush or the rubber seals .
Just a comment no real right or wrong thing , an observation . Spose someone could test the oil ? See what gives.
Just a comment no real right or wrong thing , an observation . Spose someone could test the oil ? See what gives.
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From: Nunya.
As you said something is at play an oil test might show what. It could very well be torsional stresses like you said .
I go check my tyre pressures every ride and I have noticed my rear brake disc is always hotter than my front disc. It' less than a mile to the servo where I check , I hardly use my back brake and the ABS doesn't kick in till over the speed I go to check tyre pressures . Might just be lack of clean air to the rear disc.
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From: poway
No I have not , I will if I remember, but as I said SOME heat must go through to the fork leg with the single disc .Actually my mate has one of those heat reader guns, I'll try to get him to take it for a ride when we go. We always stop at a look out just after a tight twisty section where hard braking is the key to good lap times lol.Might check them there if he's up for it
As you said something is at play an oil test might show what. It could very well be torsional stresses like you said .
I go check my tyre pressures every ride and I have noticed my rear brake disc is always hotter than my front disc. It' less than a mile to the servo where I check , I hardly use my back brake and the ABS doesn't kick in till over the speed I go to check tyre pressures . Might just be lack of clean air to the rear disc.
As you said something is at play an oil test might show what. It could very well be torsional stresses like you said .
I go check my tyre pressures every ride and I have noticed my rear brake disc is always hotter than my front disc. It' less than a mile to the servo where I check , I hardly use my back brake and the ABS doesn't kick in till over the speed I go to check tyre pressures . Might just be lack of clean air to the rear disc.
As far as rear caliper heat, it gets less air. Also if you taking later FXDs, they are only single sided calipers in the back. They probably drag a little more..
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