Early R65 Front Brake Upgrade Options

[R65North]

Hi All,

Had my '79 'Phase 1' R65 a few years now and am gradually changing bits and pieces as the years pass and time allows. My current focus is the front brake. My 79 bike has the early ATE caliper, specific to the R65 and also the optional twin disc setup. Originally it had the circular handlebar mounted MC but when that dies I replaced it with a new rectangular MC fitted to Phase 2, '81 onwards, Brembo-kitted bikes.

So, current brakes are adequate but wooden-feeling and retardation could be better. How do i improve the brakes most cost-effectively?

Options (there might be others!):

Replace original flexible hoses with some fresh
Change pads (current ones are newish and to original spec)
Replace ATE calipers with R65 Brembo calipers (if I can find a pair)
Replace OEM stainless discs with floating EBC items from Motorworks

Interested to hear from others who have upgraded from original spec ATE's.

I'd really like to keep the ATE calipers unless Brembo's offer a big improvement - but how could they given the seeming similarity of the designs?

Thanks for the opinions
Cheers
Dave

[Bob_Roller]

I have Brembo calipers on my LS, I can't tell much difference between the ATE calipers on my '81 R65 .

I replaced the OEM stainless rotors, with EBC semi-floating steel rotors and EBC organic pads, no noticeable improvement in dry braking, but I saw a significant improvement in wet braking .

I also have braided stainless lines .

If you have the original OEM rubber lines, I don't know how they fare in your weather conditions, but they are probably at least 32 years old .

You're call on that .

With everything I've done, I have not seen any real improvement, other than wet braking and I live in a desert, so I don't get those conditions that often .

I replaced these parts, as they needed normal replacement, I personally would not go through the expense of replacing these parts, if they are still in good condition .

[R65North]

Hi Bob,
Thanks for sharing your experience, it could save me a lot of time and money. Much appreciated.
Dave

[Barry]

Nothing wrong with the Ate calipers except the spares are scarce and more expensive than Brembo.

I would look at reducing the master cylinder piston size to improve the master cylinder to caliper hydraulic ratio.

[R65North]

Hi Barry,
Still got the R45 I see - I took full advantage pf your knowledge on the BMBIKES site a few years ago - many thanks!

Good suggestion about the MC, I will investigate that one.

Here's the bike last month BTW. '79 wearing 81 bodywork - I have the original but the later seat is lower and more comfortable IMO.

Cheers
Dave

[R65North]

Hi Bob,
Just saw your point on the original hoses - yes, it's something I should replace, if bleeding the front wasn't such a chew I might've done it sooner...last time ended up pushing fluid up through the calipers with a syringe to get the air out.
Cheers
Dave

[Bob_Roller]

Good looking bike !!!!!

I see you have ' gaiters ' on the front forks, I put them on my '81 and at first they looked real out of place, but after 10 years they look like they really belong there !!!!

I kind of don't understand the problems with bleeding the brakes on an R65, I've used a vacuum bleeder for the last, going on 36 years without any issues .

Used it on my cars and bikes and quite satisfied with the results .

Only better method is pressure bleeding, but that's not really possible on a motorcycle brake system, I've tried and it's quite messy .

I just noticed that you're bike is a '79 model year bike, so the brake lines are 37-38 years old, I would not hesitate to replace them, if it were my bike !!!!

[wilcom]

So, current brakes are adequate but wooden-feeling

Here is a good page for master cylinder caliper ratios.
http://www.vintagebrake.com/mastercylinder.htm

[georgesgiralt]

Hello,
When new my bike had a couple of ATE caliper and a 15 mm dia master cylinder. The feeling was spongy.
Then the MC leaked badly so Ibought a 16 mm dia MC. Feeling improved a bit.
I had one caliper with one piston rusted and this produced a "plop" when braking. At that time BMW had stopped selling pistons for the ATE. So I was forced to buy a couple of Brembos for the bike. Exactly same braking, "ploppingless" and purse empty.
In 2013 I exchanged the hoses for braided lines. The braking became excellent provided you had enough force to squeeze the lever.
If I  had some money I would replace the MC   by a 15 mm  one...
Change  your brake lines NOW.

[Barry]

The table at vintage brakes doesn't include our 36mm piston size but it gives you an idea of recommended ratios in the range 23:1 to 27:1 for opposed piston calipers. It's not rocket science to work out the relative piston areas for our 36mm pistons and produce our own ratios.

A single disc Ate caliper with a 13mm master cylinder is 15:1 so quite some room for improvement.

The later single disc with bermbo caliper and a 12mm master cylinder is 18:1

A twin disc with 16mm master cylinder would be 20:1 which is better

And with a 15mm it would be 23:1 which is better still and probably what I'd aim for.

[R65North]

Change  your brake lines NOW.

You might tell your servants what to do but I'll change them if and when I choose thanks

[R65North]

Thanks for the opinions Guys, I'm going to strip and rebuild the calipers with new hoses when I get around to it. Parts are expensive but available. The MC is a newish 15mm so will do just fine.
Cheers
Dave

[georgesgiralt]

Change  your brake lines NOW.

You might tell your servants what to do but I'll change them if and when I choose thanks

Your life, do as you please.
Too many reasons to die using a bike o add another one.

[Tony Smith]

Your life, do as you please.
Too many reasons to die using a bike o add another one.

It never ceases to astound me that people will turn a blind eye to very basic and immediate threats to their continued existence. I will put up with many things not being ideal on a motorcycle, except for brakes and tyres.


I have a particular view of the intelligence, or rather the lack thereof, of anyone prepared to gamble with either.


A 1979 R65 with original brake lines that are now 37 years old is quite simply a failure looking for somewhere to happen - no equivocation whatsoever.

Now I am also firmly of the belief that an adult should be allowed to do pretty much whatever they want to do providing they don't hurt others. Sadly, ridign a bike with dangerous brakes is somethign likely to hurt others besides yourself.


I recommend the OP sells the motorcycle and buys a revolver - there is a game he might like involving a revolver and one round in a random chamber.

[davidpdx]

As Clint Eastwood so succinctly put it "Mans got to know his limitations". I happily rode my 1946 Triumph Speed Twin with nothing but a rear drum brake for years. Anything with a disc brake is such an advancement over the bikes of the past. Just got to know your limitations...