Older Magura & Grimeca System 8's
Two separate questions:
1.) I'm working on an old Cannondale Super V for a buddy, and it has a pair of older Magura Louise discs. All of the instructions I've been able to find show brakes with a seperate bleed screw, that these do not. Does anyone have any tips or advice on how to bleed these?
2.) I've got parts to equip my second bike with a set of System 8's. I've got a pair on my first bike and love them. Unfortunately, I'm missing the front handle / reservoir. I've been watching E-bay, but nothing so far. Would another brands brake lever work?
The old shimano 4 piston brakes (M755s) were manufactured under licence from Grimeca and were a copy of the System 8 brakes. Shimano levers are interchangeable among its calipers, so you can use any of the shimano line, but for one thing.
Shimano uses mineral oil in its brakes and the seals are said to not be compatible with brake fluid, which is what Grimeca uses.
Thanks Tim. I was aware that the old XT's and SRAM brakes were of the same design, and I was aware of the XT's using mineral oil (not sure about the SRAMS). Needless to say, given the age of these, parts are hard (er) to find, which is why I was considering, and asking, if it was possible to use these with someone else's levers, ie Hayes.
I should probably start a new thread, but figured the two of you might know what you're talking about (sorry for the hijack). I am also doing work on a buddy's bike- it's a 1998 Specialized Team FSR DH rig. The bike has Grimeca hydros on it, and I've never worked on these before and can't seem to find ANY info on them anywhere. The calipers are red, the rotors are "DE- 200's". I haven't gotten them apart yet, so can't tell you if they're four or six piston jobbies. My questions: 1) the front rotor is bent. I can't seem to find a replacement from Grimeca- assuming any 200mm rotor will do? 2) Any tips on bleeding these bad boys? They have the external reservoir cup up top on the levers, but no apparent bleed ports, and from what I HAVE found, they use DOT- just don't know what weight. Any help is greatly appreciated.
There's no app for this.
Here's some info on '99 Louise...
I had some 2000s but forget the setup, sorry, but this is on the internet:
If it is necessary to bleed the Magura system, you must use Magura 5W fluid, available from Magura.
This is the same fluid that all Magura hydraulic brake systems use. Additionally, you must either use
the Magura bleeder fitting to attach the syringe to the caliper, or may simply use the syringe by
twisting the syringe nozzle into the threaded bleed port on the caliper. Consult the Magura instruction
manual for the fluid bleeding process.
Alshead, you can tell if they are 4 piston by looking at the opening in the top of the caliper and seeing how many pistons push the pads. Also, each piston is "outlined" on the caliper body, so 4 piston calipers have 2 "outlines" on each side.
Originally Posted by alshead
Here's a picture of the system 8 (4-piston version):
Yes, any 200mm rotor will do, but they may be hard to find. I have a 200mm rotor on the rear with a Grimeca adaptor and a 203mm shimano rotor and adaptor on the front. But I can only swap rotors if I also swap adaptors. You might be better off finding a 203mm rotor and adaptor if you can't straighten the rotor (have you tried it's usually pretty easy).
If you have the system 8 version, then the bleed nipple is next to the hose. I just use the car bleeding technique (fill the reservoir, pump the lever a few times and hold it closed while opening the bleed nipple. Close the bleed nipple and the repeat the previous steps, making sure that the reservoir remains full).
For the DOT fluid, standard car brake fluid will do.
Last edited by Wombat; 01-10-2010 at 11:18 PM.
Official ***** Idiot
For the guy asking, no, you cannot use Hayes levers on Grimeca/Shimano brakes. Different size pistons in the levers. Hayes don't push as much fluid, so popping them on older Shimano brakes will not work. That's assuming you could even get the lines to fit.
Don't try to switch fluids. DOT fluid has a swelling agent in it. If you put DOT in a brake designed for mineral oil, the seals will swell and cut off a good part of the fluid flow. It'll also slowly dissolve the seals.
I believe the Grimeca's used DOT 5. Don't use DOT 5.1, it's a different base. DOT 3 and 4 are the same base chemical as 5.1. DOT 5 is silicone based, the other three are polyglycol ether based. Make sure you use the right fluid, you can't mix 5 with any of the other three.