Better disk on '75 R75/6

Discuss all things 1970 & later Airheads right here.
Abstruse1
Posts: 41
Joined: Thu Jun 11, 2015 10:31 am

Re: Better disk on '75 R75/6

Post 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...
Abstruse1
Dallas, USA
Blonds aren't the only airheads.
Major Softie
Posts: 8900
Joined: Tue Aug 03, 2010 1:46 pm

Re: Better disk on '75 R75/6

Post 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.
MS - out
Abstruse1
Posts: 41
Joined: Thu Jun 11, 2015 10:31 am

Re: Better disk on '75 R75/6

Post by Abstruse1 »

What's your guess on optimum MC diameter?

Any great pads to recommend?
Abstruse1
Dallas, USA
Blonds aren't the only airheads.
Major Softie
Posts: 8900
Joined: Tue Aug 03, 2010 1:46 pm

Re: Better disk on '75 R75/6

Post 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.
MS - out
Abstruse1
Posts: 41
Joined: Thu Jun 11, 2015 10:31 am

Re: Better disk on '75 R75/6

Post 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.
Abstruse1
Dallas, USA
Blonds aren't the only airheads.
Major Softie
Posts: 8900
Joined: Tue Aug 03, 2010 1:46 pm

Re: Better disk on '75 R75/6

Post 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.
MS - out
chasbmw
Posts: 765
Joined: Fri Aug 06, 2010 7:40 am
Location: Bath UK

Re: Better disk on '75 R75/6

Post 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?
Charles
Image
Replica 1070 R90/S (based on 82 RT)
1975 R90/6
Abstruse1
Posts: 41
Joined: Thu Jun 11, 2015 10:31 am

Re: Better disk on '75 R75/6

Post 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.
Abstruse1
Dallas, USA
Blonds aren't the only airheads.
chasbmw
Posts: 765
Joined: Fri Aug 06, 2010 7:40 am
Location: Bath UK

Re: Better disk on '75 R75/6

Post 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.
Charles
Image
Replica 1070 R90/S (based on 82 RT)
1975 R90/6
chasbmw
Posts: 765
Joined: Fri Aug 06, 2010 7:40 am
Location: Bath UK

Re: Better disk on '75 R75/6

Post 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.
Charles
Image
Replica 1070 R90/S (based on 82 RT)
1975 R90/6
Post Reply