New Rotor Rub.

wilkij1975

Hi

I have just fitted a new Superstar floating rotor to my Avid Elixir 5's. Fitting was no problem but it seems to rub no matter how much setting up I try.

Is this just down to the new rotor being a little thicker than the old one and will it bed in (if I can ride it with all that drag of the rubbing!) or will the brakes need a bit of bleeding to take some oil out?

Cheers All

peter413

Is it rubbing against the pads or something else?

wilkij1975

Its on the pads i'm sure. I have checked the clearance of the spider rivets(?) and its fine (I was worried about that). Can't see anything else that would rub.

cooldad

Push the pistons in a bit, centre the caliper and try again.

Anonymous

Ditch the floating rotor and get a normal one.
Floating rotor and fork/brake/hub compatibility is sketchy at best. Just not worth the hassle, frankly.

paulbox

cooldad wrote:

Push the pistons in a bit, centre the caliper and try again.

What he said.

Anonymous

I'm almost certain the disc itself will be catching on either the calliper body, the brake pad backing, or even the fork. No amount of piston resetting or bleeding will solve that.

cooldad

They do seem to have a lot more problems than they are worth, which seems like nothing over a standard rotor.

nicklouse

if you are keeping them stop playing with them and use them. they will neeed to bed in again.

the pads will also need to bed in every time you adjust the caliper.

so set the best you can and just use them.

But as above floaters are a pain.

wilkij1975

Thanks for the suggestions. Wasn't aware that floating rotors were a pain compared to normal ones. Why is that?

andrewjoseph

I've had no problems with my hope floating rotors. I was not aware they are supposed to be terrible. Since having floating rotors i get little of the warping I was having before, and it usually sorts itself out after a bit of use.

If they fit without rubbing anywhere, then,as stated above, just make sure the pads and pistons are pushed fully home, recentre caliper, check and ride.

Anonymous

wilkij1975 wrote:

Thanks for the suggestions. Wasn't aware that floating rotors were a pain compared to normal ones. Why is that?

Because the spider, and the rivets that hold the braking surface to the spider are wide enough to cause compatibility issues. On some hub and fork combination, the spider itself can actually contact the fork leg, wearing it away slowly.
But more commonly, it is the calliper or the brake pad backing that contacts the rivets. Particularly on Avid Juicys. Some people run then with no problems - which frankly I cannot fathom, as there is just no way the rivets could pass my callipers without contacting the pads.

andrewjoseph wrote:

I've had no problems with my hope floating rotors. I was not aware they are supposed to be terrible.

They're not terrible at all. Nobody said that. What they are is pointless, largely. If you use them with Hope brakes, then they'll be fine, but it's very hit and miss with other brakes.

And frankly, if you had warping issues with your non floating rotors, then something is seriously wrong somewhere.

andrewjoseph

yeehaamcgee wrote:

....
And frankly, if you had warping issues with your non floating rotors, then something is seriously wrong somewhere.

Yeah, I brake so hard i start melting steel.

On all the brakes I've used with solid rotors (i.e. not 'floating'), warping was an issue, and still is on my wife's hopes. They required constant straightening.

i know this is heat related, as several times i have had vapours coming off new pads and the steel is discoloured due to heat.

I tend to brake hard and sharp. but when I'm taking novices out, I have to drag my brakes to keep pace with them.

i use sintered pads so this may exacerbate heat issues, but I use the same pads on the floating rotors and don't get warping.

Anonymous

Sintered pads says it all really. The locals in French DH resorts laugh at the silly brits with their sintered pads

Vapur sounds wrong though. I often ride very long descents, where you have to keep your speed in check - if you don't, there's no way you'll slow down later - and have boiled, glazed and damaged a while host of brakes, but the only time I've had vapour coming off the brakes was when I had some contaminant in the pads.
And the only time I warped discs was way back in the very crappy Diatech cable disc days.

andrewjoseph

the vapour came of brand new pads that I hadn't pre treated by heating them.

sintered pads last me approx 4-6 months. non sintered last me 4-6 weeks.

the heat issue is managed with floating rotors of 207mm (?) diameter rotors.

wilkij1975

Well I checked everything and the rubbing was deffinately on the pads. There were no issues with clearance on the rivets, fork etc as suggested. I tried pushing the pads back and re-centering but that didn't work. I put the old (slightly rusty spidered) disc back on so I can ride without constant front braking and will try again soon.