Brake upgrade for 1984 R65: Brembo F08 --> F09?

[qwerty123]

Hello everyone,

I'm looking for excuses to tinker, and I've got it in my head that braking could be improved on my mostly-stock '84 R65.

The only modification to the front brake at present is a Spiegler stainless steel line. This really firms up the lever.

Given that very firm lever (and attendant lack of lever travel), I was thinking it might be good to move from a 38mm F08 caliper to a 48mm F09 caliper. How does this idea strike you?

I haven't figured out the details yet, but the idea is basically this: it's probably the best bang for your buck that I can see for R65 brake upgrades IF the mounting holes and other relevant specs for the F09 are the same as for the F08. If so, it's considerably cheaper than upgrading to the dual disc setup and it should just bolt up.

It looks like it'll give quite a bit more mechanical advantage (going from 20:1 in the present setup to 30:1 with the 48mm F09).

I'm planning on sticking with a stainless disc and maybe upgrading pads to EBC HH or whatever the internet recommends.

So, is this a good idea? Does it make sense? Should I just keep my greasy fingers off the bike? Thanks for the thoughts...

[wilcom]

Is it already a 2 disc set up? if not , that's the direction I would take. If it doesn't stop with dos disc's there's a problem.

[qwerty123]

It's currently the stock single-disc setup, which works fine.

I am thinking about the F09 because it seems both a lot cheaper and a lot easier than the whole dual-disc upgrade.

[mrclubike]

Another way to go is a smaller Dia MC
They do show a 12mm on Moto Bins
But the F09 may be a cheaper route from MG cycle
http://www.mgcycle.com/index.php?main_page=index&cPath=110_115
Let us know how it works
Iam useing a 12mm MC with a 38mm F08 and spiegler line It works great

[DonC]

I'm with wilcom ... dual discs.

[qwerty123]

Thanks for the MG Cycle tip, it looks to be a good price!

I believe stock master cylinder diameter on a 1984 was 12mm, so I think that's what I've got. I find the 20:1 ratio with the 38mm + Spiegler lines to be too stiff, plus I don't think I can do a stoppie.

[mrclubike]

Have you checked to make sure it has the correct 12mm MC
The previous owner of my bike stuck a 15mm on it
Needless to say I  had to replace it with a 12mm
The size is cast into the bottom side of the cyl

[tunnelrider]

The firm lever as a stock F08 IMHO is a good thing.  As you said the F08 works fine and like you I have no problem washing off speed open road riding or tight and twisties on the standard F08 braked R65 with two fingers on the brake.  I'll admit I don't ride sports bikes so don't appreciate the difference modern brakes have, but then again the R65 is hardly a sports bike either.  Maybe you are doing the upgrade totally for stoppies, then yeah it'd be a great idea!  I recently softened my lever by getting a master cyl overhaul kit.

[qwerty123]

I found time to check the master cylinder size: it's the stock 12mm

[nhmaf]

The EBC organic brake pads are the ones to use with the stock stainless rotors.  Do NOT get the HH sintered metal pads as they will chew up the stainless rotors in short order, and then you'll have even more expensive stuff to replace.

[Tony Smith]

The previous owner of my bike stuck a 15mm on it
Needless to say I  had to replace it with a 12mm
The size is cast into the bottom side of the cyl

Do you by any chance still have it and would you like to sell?