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79 R100 /7 Brakes

G

griffgriffin

New member
I am looking for advice on updating the brakes on my 79 R100 /7. I am thinking about either getting a Brembo caliper or updating to an RS front end to gain the dual calipers. (If that is possible)
Has anyone tried either of these or do you have any advice for me? If you have updated the caliper, what brand/model have you found to work the best with minimal milling?
 
Welcome to the forum! I'm guessing you have just the single ATE front brake. Depending on what your real goal is, the cheapest and first step would be to add the handlebar master cylinder if you have the under tank version. My '78 /7 has the under tank master cylinder.

A relatively straight forward conversion would be to add the second disk on the right side. It gets more complicated with more parts if you go to Brembos, or grafting another bike's front end. Snowbum has some discussion on various considerations here...look for ATE conversions about halfway down the page:

http://bmwmotorcycletech.info/brakes.htm
 
Hi. Thanks and thank you for your reply. Yes, single side caliper. I found the page you linked doing a google search and it has been helpful. He does not discuss replacing the front end, however, and he doesn't call out the specific caliper, or at least I don't know how to find the specific one when I google "Brembo 4 spot brake."
 
Brembos

On my /7 I swapped the ATEs for Brembos back in the day, but I had dual ATEs. If I recall correctly the mounting points on the sliders are different so my solution was swapping out the whole fork set up. I think I also put on the stainless brake lines at that time but left the m/c. Overall, much better braking.
 
I've been doing a few pre-'81 master cylinder upgrades recently. Everyone is very happy with them, as they should be: it's a fantastic improvement to the feel and power of the brakes.

It costs $450-ish for bikes like yours (new handle unit, grips, MC, brake hose, a few other parts). People with '74 models who want to update both sides can be in for close to twice that because they need new switches and a new left side control unit.

You might find that just upgrading the MC gives you the improvement that you are seeking without adding a second caliper. However, just adding a second caliper could be more cost-effective depending on what you can buy used parts for.

If you want to discuss options, feel free to contact me.
 
switching to brembo

If you replace the /7 ATE fork assembly with a Brembo fork assembly, you will no longer be able to use /7 wire spoke wheels (if your bike came with them), and will have to get cast BMW snowflake wheels. That makes adding a second ATE brake caliper/slider less expensive. I used stainless braided brake lines with sintered metallic brake pads on cast iron rotors with the ATE dual caliper front forks on my 77RS and got good results.
 
Great stuff guys, thanks. I think I have enough info to get started.

BTW, I went to the DMV today to get the title transferred, and the 79 R100 /7 he sold me turns out to be a 78 R100 /7 RS. LOL! The guy I bought it from had it for 18 years and he bought it from the original owner, with all the original purchase documents. How do you not know what year and model your bike is??!!??
 
Look at the top of this thread:

https://forums.bmwmoa.org/showthread.php?47142-Resources-and-Links

There are a number of ways to determine when the bike was built. Remember that BMW model years go from September to August of the next year...it's not by calendar year. Check out your VIN and see if things are correct per the DMV. I'm a little amazed that a person at the DMV would really know the difference. He must have some sort of table.
 
/7 or RS

On the right side steering head gusset on my 77 RS the vin number has the model id stamped next to it. In this case, 'R100RS'. If your bike is a 78 or 79 RS it will have a similar stamping. There is a plate riveted to the same gusset which contains the vin number and the date of manufacture. The engine number on the dipstick boss should match the steering head number but after 40 years might not.
 
On my '78 R100/7 (not the RS) it made a huge difference to go to handlebar master cylinder than to try using the old M/S with anything. The old M/S may have been OK in its day, but is junk in my opinion.

Doing as I did, did not cost anywhere near $450.00

Call Rusty @ Max's BMW and he can help you find differing options that can save you money. (like using the original 2-cable throttle set-up with some newer throttle parts on the handlebars - like the throttle tube with the grip already installed, etc.

The only other thing I had to do was to have a local hose mfg. make me a brake hose to go directly from the new M/S down to the brake caliper w/o having to buy the plenum - but you should also have to buy the newer brake light switch.

You need not go to stainless brake hose. IMO a waste of money!
 
Great advice! Thank you.

Did you use the existing caliper? Did you consider upgrading to a modern 4 piston? Did you add HH brake pads or any other such thing? I've bought myself a little time as I've decided to rebuild the front end and all the gaskets are coming from Germany.
 
griffgriffin said:
Great advice! Thank you.

Did you use the existing caliper? Did you consider upgrading to a modern 4 piston? Did you add HH brake pads or any other such thing? I've bought myself a little time as I've decided to rebuild the front end and all the gaskets are coming from Germany.
Click to expand...

I personally tried to keep the costs down, so I used existing caliper, and existing throttle cables (2). However, on this type of bike, and its age (mine was 39 years old) I thought the single caliper with new pads and new handlebar M/C was awesome compared to the old one, and I thought it did just fine. You may want more performance though. Be careful, because you can literally put thousands more into this bike, and in the end, you will never get out of it what you have in it. Unless, perhaps, you just happen to enjoy it for yourself and want to keep it forever!

If you are a mild, non-aggressive rider like me, you should like the existing single caliper (just rebuild it, too).
 
If you are a mild, non-aggressive rider like me, you should like the existing single caliper (just rebuild it, too).[/QUOTE]


Thank you!
 
My single caliper was unbelievably better with the upgraded handlebar m/c. While I know it is tempting to upgrade everything, on my R100 which wasn't the greatest in power, so I would suggest that upgrading to the handlebar m/c would be enough.
 
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