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Re: Better disk on '75 R75/6

Posted: Fri Jul 17, 2015 6:23 pm
by Abstruse1
Well, here's my Plan A. I'm putting on dual ATE calipers with EBC disks. Maybe this will be adequate. If not...

Re: Better disk on '75 R75/6

Posted: Fri Jul 17, 2015 6:37 pm
by Major Softie
Abstruse1 wrote:Well, here's my Plan A. I'm putting on dual ATE calipers with EBC disks. Maybe this will be adequate. If not...
It will never be awe-inspring, but, with the right master-cylinder and pads, it should certainly be more than adequate.

Re: Better disk on '75 R75/6

Posted: Fri Jul 17, 2015 9:19 pm
by Abstruse1
What's your guess on optimum MC diameter?

Any great pads to recommend?

Re: Better disk on '75 R75/6

Posted: Sat Jul 18, 2015 4:47 am
by Major Softie
Abstruse1 wrote:What's your guess on optimum MC diameter?

Any great pads to recommend?
I still don't understand exactly what these discs you have are. You say they're not stainless, but you don't think they're cast iron? So, what are they? That affects the pad choice.

If they can handle HH, I'd totally go there. That gives you both great dry braking, and wet. If they're cast, then you want organic or semi-metallic.

Re: Better disk on '75 R75/6

Posted: Sat Jul 18, 2015 10:14 am
by Abstruse1
Here's all I know about the disk (from EBC's description):

The worlds only complete line of direct bolt-on brake discs made in EBCs UK manufacturing plant using: Billet-steel rotor rings that deliver 18 percent more stopping power than stainless steel equivalents.

EBC Pro-Lite rotors are complete bolt-on and go rotor assemblies made with forged aluminum center hubs, high friction billet steel rotor rings and sturdy riveted construction.

EBCs solid HPSR rotor programs are low carbon steel units zinc plated to minimize corrosion.


Someone -- EBC, I think -- says their HH pad isn't compatible with cast iron disks. I don't know if "cast iron" includes "billet-steel." I'd think not, but may be wrong.

Re: Better disk on '75 R75/6

Posted: Sat Jul 18, 2015 3:31 pm
by Major Softie
Abstruse1 wrote:Here's all I know about the disk (from EBC's description):

The worlds only complete line of direct bolt-on brake discs made in EBCs UK manufacturing plant using: Billet-steel rotor rings that deliver 18 percent more stopping power than stainless steel equivalents.

EBC Pro-Lite rotors are complete bolt-on and go rotor assemblies made with forged aluminum center hubs, high friction billet steel rotor rings and sturdy riveted construction.

EBCs solid HPSR rotor programs are low carbon steel units zinc plated to minimize corrosion.


Someone -- EBC, I think -- says their HH pad isn't compatible with cast iron disks. I don't know if "cast iron" includes "billet-steel." I'd think not, but may be wrong.
Yeah, I can't find anything at EBC about what pads are compatible with those discs, but, like you, I would guess that HH would be fine. It would be nice to not have to guess though.

Re: Better disk on '75 R75/6

Posted: Sun Jul 19, 2015 2:41 pm
by chasbmw
The discs are floaters, stainless steel rotors, a bit thicker than the OEM rotors.

I used HH pads when these discs were on my brembo or equipped 82, I found them a bit harsh. Discs have been moved to my 75 90/6 and am using ferodo Platingnam pads. I expect that they will work well.

Can you get HH pads for ATE brakes?

Re: Better disk on '75 R75/6

Posted: Sun Jul 19, 2015 3:35 pm
by Abstruse1
So far, I haven't found HH pads for the ATE calipers. It's reasonable that they aren't made. Perhaps one could find a large enough HH pad/backing plate and cut out the ATE profile and weld on the pack pins.

Re: Better disk on '75 R75/6

Posted: Sun Jul 19, 2015 4:41 pm
by chasbmw
That sounds silly
Abstruse1 wrote:So far, I haven't found HH pads for the ATE calipers. It's reasonable that they aren't made. Perhaps one could find a large enough HH pad/backing plate and cut out the ATE profile and weld on the pack pins.
I suppose you could do that, but it might not be safe.

Airheads don't really behave well if treated like a modern sports bike, they can get a bit confused. Better to brake into the turn and then take the bike through on a gently rising throttle. If you modify your brakes as I have suggested you will have more than enough brakes for the tyres and suspension and you won't need to use aggressive brake compounds which will tear into your new brake discs.

Re: Better disk on '75 R75/6

Posted: Sun Jul 19, 2015 4:46 pm
by chasbmw
That sounds silly
Abstruse1 wrote:So far, I haven't found HH pads for the ATE calipers. It's reasonable that they aren't made. Perhaps one could find a large enough HH pad/backing plate and cut out the ATE profile and weld on the pack pins.
I suppose you could do that, but doing it safely might be a challenge

Bmw airheads don't really react that well to aggressive braking, a smooth riding style works better with them.
If you modify your brakes as I have suggested, you will have more than enough brakes for the bike's tyres and suspension and you won't need aggressive pad compounds that will wear out those brand new rotors.