Magura rim brake questions

I'm interested in buying a Magura HS66 hydraulic brake. From the exploded
diagrams I've found on the web, it appears that it would be possible to add
a supplementary lever to each brake by connecting one lever to each slave
cyclinder and linking the slave cylinders as normal. Can anyone confirm
that this is the case?

I'm also interested in general intercompatibility between rim brake models
(I know that the disk brakes aren't compatible with the rim-brake levers).
Are the various series of rim brakes broadly intercompatible?

Thanks,

James Thomson

I'm also interested in general intercompatibility..

James - Magura has used two different cylinder sizes in their hydrauli
rim brake levers, 16mm and 14mm. They have used only one diamater on al
of the slave cylinders

The current HS-11 and HS-66 use 16mm, and the HS-33 uses 14mm. The earl
(but no longer produced) HS-22s used 16s, then switched to 14s in late
production models. Theoretically one can use either size lever cylinder
but you'd probably want to match sizes on a dual lever system. The 14m
cylinders develop a little more "power", at the expense of slightly les
slave cylinder/pad travel

Joh


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...it appears that it would be possible to add a supplementary lever t
each brake..

James - Your other questions intrigued me, so I checked out some of m
Maguras after making the first response

If you're planning on connecting the 2nd lever to the "bleeder port" o
the slave cylinder, there's a problem. The thread on that port i
different (smaller) than the other three ports that accept hos
fittings. So, you would have to retap it (might be difficult to get
good sealing surface), use two of the cylinders with two hose fittin
sized ports, or "T" into an existing line somewhere

Also, I think it might be best to ask Magura if the seal or sto
mechanism on the lever/cylinder not being used can withstand ful
"backwards" pressure in it's outermost position. An HS-66 lever ma
actually be better than an HS-33 in that respect, as it does not hav
"thumb adjusters"

One other thing that might be best to avoid if you're going to b
scrounging for levers/cylinders is the "composite" levers used on th
HS-11 and some OEM systems. The metal ones are much better, from both
feel and durability standpoint

If you havent already found it, plug "Magura Cult" into Google, an
check out that website

Joh


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"jmm" wrote:

If you're planning on connecting the 2nd lever to the "bleeder
port" on the slave cylinder, there's a problem. The thread on
that port is different (smaller) than the other three ports that
accept hose fittings. So, you would have to retap it (might be
difficult to get a good sealing surface), use two of the cylinders
with two hose fitting sized ports, or "T" into an existing line
somewhere.

Thanks for the input. It looked to me as though the link hose and bleeders
use the same barbed fitting (the online service manual makes no distinction
between the two) and therefore the same thread. The parts diagram on the
Magura website labels the two slave units 'M6/M6' and 'M6/M8' which I'd
interpreted as the threading.

I'm not clear why the main hose and link hose use different fittings. Any
idea?

Also, I think it might be best to ask Magura if the seal or stop
mechanism on the lever/cylinder not being used can withstand
full "backwards" pressure in it's outermost position.

Good point.

If you havent already found it, plug "Magura Cult" into Google,
and check out that website.

I had checked it out, but thanks for reminding me of it again. I found the
information about master piston diameters, and a few other useful facts,
though nothing directly related to using supplementary levers.

I think maybe I should just get my hands on a set and start experimenting.
I've found posts in the deja archive from an employee of Magura USA who
says that this is not only possible, but "real simple to set up".
Unfortunately, my emails to Magura are -so far - unanswered.

James Thomson

The parts diagram on the Magura website labels the two slave unit
'M6/M6' and 'M6/M8' which I'd interpreted as the threading. I'
not clear why the main hose and link hose use different fittings
Any idea

James - It almost seems that the designations you mention from the part
manual are backwards, at least by my way of thinking. It would seem t
make more sense if they were M6/M8 and M8/M8, here's why

One cylinder has two of the "larger" tapped ports that definitely appea
to be threaded the same. One port is for the barbed fitting on one en
of the crossover tube, and the other accepts the hose from the lever
secured via a ferrule and compression nut. The male threads on a barbe
fitting and lever hose compression nut appear to be identical, and
have switched the port that each of these goes to in the past, fo
"routing" purposes

The other cylinder has two different sized ports. The larger one i
the same as both of the ports on the other cylinder, and accepts th
barbed fitting on the other end of the crossover tube. The smalle
port accept the plug screw that you remove to bleed the system, an
that's the oddball one that I though you were going to try to connec
a second lever to

By the way, I haven't used HS-66s, and can't remember whether they com
with a booster (bridge). I thought some of the frames I've used Magura
on had pretty beefy stays and brake pivot bosses and therefore wouldn'
need a booster. I was wrong, I haven't seen an installation yet tha
didn't benefit significantly from using a Magura booster, given th
force that these brakes can develop (particularly the 14mm pisto
versions). I've used their steel, alloy and carbon fiber versions, an
would say they all perform about the same, you just pay more as you mov
down the weight sacle

Also, I've been using Magura "Red" compound pads lately, wet or dry. I
is my understanding that these are made by Koolstop for Magura, an
certainly appear to be the same as the Koolstop "Salmon" pads I wa
using in all my V Brakes before switching to Maguras

Have fun tinkering if you go for it. These are truly great brakes whe
set up properly

Joh


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