old brakes

[paulfinney2]

76 R75/6 38,000 miles. Rebuilt brakes with new piston, pads, hose to mc under tank. Properly adjusted. Now I have brakes a good as they should be, but still characteristically bad. I think I have read that replacing the under tank mc with a handle bar mounted mc will improve the braking capabilities. Is that right? And if so, is it a simple transition? I would probably use braided brake lines.
With the single exception of the brakes, the bike is just a charm to ride.

76 R75/6
86 R80RT

[flash412]

76 R75/6 38,000 miles. Rebuilt brakes with new piston, pads, hose to mc under tank. Properly adjusted. Now I have brakes a good as they should be, but still characteristically bad. I think I have read that replacing the under tank mc with a handle bar mounted mc will improve the braking capabilities. Is that right? And if so, is it a simple transition? I would probably use braided brake lines.
With the single exception of the brakes, the bike is just a charm to ride.

76 R75/6
86 R80RTWhat brand and formulation brakes pads did you get? (Yes, options are limited for the ATE caliper.) That makes a BIG difference. Did you bed in the pads? Maybe they have "green fade." Installing a stainless steel line from the master cylinder to the caliper will improve response, especially if the current rubber line is THIRTY YEARS OLD.

How to bed in new brake pads...
Find yourself a road out in the middle of nowhere. While riding, do several hard stops in succession. Then ride while dragging your brakes until they fade. You WANT them to fade because you want them to get hot enough to burn aromatics out of binding compound. Once they fade, stop and take a break for a while until the disk cools enough to touch. If green fade was the problem, they should work a whole lot better after bedding them in.

[russbritt]

I have the under tank cylinder, braded steel lines. All done by previous owner, brakes are good for an old bike, nothing like a new bike, but its not a new bike.

[paulfinney2]

I can't tell you what brand the brake pads are, but I bought them from my BMW dealer, also the new rubber brake line. And for breaking in, I did a lot of hard braking, especially down steep hills.

[lostboy]

Converting to a handlebar master cylinder makes a HUGE difference. It can be an expensive proposition; you'll need the right control and throttle cam from an '85 on twin, an appropriately sized master cylinder and of course, an upper brake line. I'd reccomend a 12 or 13mm master cylinder.

[mikeb921]

I don't know if it's worth it to you, but you could always add the second disc and caliper. You would have to find a fork leg that's made for caliper install. The master cyl would also have to be upgraded to a dual caliper set up.
The R75/6 was a "single disc and caliper" wasn't it? The parts could be used (not new) to save money. Just make sure everything checks out before you put it in service.

Ride Safe
Rideoften

[paulfinney2]

I've already decided not to make the dual disc conversion; tempting, but the cost is too high. Lostboy - what bike did you do your conversion on? and did you go dual disc? or why do you say '85 on for parts?

[Isamemon]

from what I understand , converting to a handle bar master is real nice, but the small parts can cost big
unless you have a newer donor bike.......
right hand contol, new cables and splitters to the carbs, some new wiring, different hoses, and of course the dual disc set up in the front
I have not done the swithc myself to handle bar m/c
and I don tknow if this is true, but a friend told me that I would also have to switch to a newer left hand control also as my bike has the turn signals on the right handle and that also moves to the left wiht the change
guess it depends on what year you pull parts from

aside from that, sticking with a single disc, stainless lines, new cable, and EPE ( not bmw) pads will make a big difference
switch to a dual disc, rebuilt undertank m/c, stianless lines and epe pads and you can tell the difference from the above upgrade
even still, your riding a 30 year old bike with brakes that were "OK" for their time
just dont rely on the back brake, that was designed to modulate speed, not stop a bike (IMHO)

[lostboy]

I've done a number of these conversions, with single and dual discs. The '85 on control is preferred as they use dual throttle cables as opposed to the '81-'84 bikes, which use 3 cables and a splitter. Your existing right switch will fit on the new control; replacing the left control and switch is only neccesary on '74 and earlier.

[BubbaZanetti]

a question for the airhead experts:

i watched a friend install Nissin 6 pot calipers (Suzuki Hyabusa brakes) on his 99 Triumph Thunderbird Sport. He had a custom bracket made for the mount and had to change his lines, but aside from that, it was a pretty clean install.

what are the limiting factors to doing this on an airhead? is it the older rotors that aren't compatible with newer style calipers?

i would think updating the ATE's with a more modern substitute would do a lot more than new lines or moving the mc...........:scratch

[paulfinney2]

There are some posts missing between Bubba's and this one, but.....

Project completed. I installed a steel braided brake line, sanded the disc to remove glaze, scraped and sprayed the pads to refresh their surface, put in new brake fluid. Also loosened the brake cable from the lever to the mc, sprayed the mc terminal with contact cleaner, relubed and retightened; it gave me a much different feel and grip on the brake lever and the brake itself. Headed down several steep hills and braked as hard as I could to seat in. The brakes on this old '76 are now much better than they were, and probably won't get much better.

Thanks for all your collective input.

[Isamemon]

a couple of things to remember
1) your riding a 30+ year bike
2) BMW had the best available.... at the time

but if your riding newer bikes, then, in comparison, the old airhead brakes are nothing more then speed modulators
and the above suggestions will make a BIG difference

dont take me wrong, my old airhead is my favorite ride ( for machines anyway);)



( I ride many bikes and horses, just picked up a ......( dont shoot) .....79 Honda to restore and go away)

[OHScot]

Just put EBC brake pads and new flex line on my R75/6. It stops OK, but woeful compared to my K1200. As I said in the title, make sure you leave some more room. Back in the 70's the brakes were OK compared to the rest of the traffic, not so good in 2008.

PS. thought briefly about dual disc's but it seemed to be a lot of expense for still not getting up to modern standards.

[boxerr]

Go to ADVrider.com, and old skool section, type in nissin in the search section, and all will be revieled.
Update to nissin 4 spot caliper on R100GS/PD is a common thing, and not overly expensive(caliper off Ebay) new hose, and there is even a drawing of the mount(maybe different to your model though)
No reason why it cant be done to any early BMW.
Worth a look at the least.

I am doing my GSPD at the moment.

[lostboy]

The stock spoked wheel won't clear most opposed piston calipers-unless you install a larger than stock disc.