Brakes

You know, it constantly amazes me that so many people are against using a disc brake on the rear of their bikes. I know some people have tried them but it sure seems like there are a lot more people talking bad about them than have actually tried them. Just so you know, I've run 2001 Magura Louise with standard black pads on both front and rear of my past three bikes (2001 Megamo 26 Pro, 2002 Echo ES2 and 2003 Echo ES4). I'll NEVER go back to rim brakes. I can ride wet or dry, hot or cold and never have to fiddle with tar or grinding anymore.

I would bet that most people who have tried a disc brake on the rear just didn't get it setup right. I'm not questioning their competance or anything, it's just that a rear disc brake requires quite a bit more finesse than a front.

The biggest problem is that most frames don't have the disc tabs perfectly aligned. We all know how finicky rim brakes can be about pad alignment. Well, disc brakes seem about 10 times more sensitive. At first, I was able to get by decently well with some creative work with the 0.2mm spacers. But, once I finally got the disc tabs evened out using a Hope Spot Facing Tool, my rear brake has improved immensely. You cannot imagine how much better a rear disc brake works once it is aligned properly.

The second thing is bleeding. Since disc brakes work at a much higher pressure than hydraulic rim brakes, they are much more sensitive to air in the lines. Even bubbles only the size of the tip of a sharpened pencil have a noticeable effect. I've recently got my hands on the new blue "Royal" blood from Magura. It seems to be just the slightest bit less viscous than the green and so air bubble can escape faster.

Before you even start thinking about bleeding, take out your fluid and leave the bottle sitting still for about 20-30 minutes to let the bubbles generated by movement rise out. When you are ready to begin the bleeding, try to be very careful not to jostle the fluid around, creating new bubbles. Follow the normal bottom-up bleeding procedure outlined in your manual.

After you have filled and drained the master reservoir 2-3 times, push enough fluid into the reservoir so that it just barely starts to overflow the edge. This is VERY important! Any space left between the top of the fluid and cap will cause the brakes to feel spongy and reduce the pad travel.

Lastly, before removing the syringe, push on the syringe plunger and work the brake lever back and forth to move fluid in and out of the system. Take careful notice to see if any bubbles come into the syringe line and make sure to get them out of the brake system.

For those few of you out there that are running a rear disc brake, try these steps and write back here to tell everyone your results. I suspect you will be amazed how much your brakes will improve.

Lever feel is so subjective...there are certain advantages to a hard or soft feel. I generally prefer the harder feel of Magura's or my Hope discs, but the Magura's tend to be too blocky for me. I end up with tendonitis if I ride often. I'd rather have a soft feel and be able to ride. I'm looking forward to running my Maggie with the RB lever again. I completely agree with Andrew about the need to set up an HS-33 PERFECTLY in order to get it to work optimally. It's compounded when you use an RB lever because the pads need to sit closer to the rim to account for the reduced slave piston travel, and further compounded if you use a soft pad (like the plaz) which squishes and flexes when the brakes are applied.

Some time in the not too distant future, I'll be selling a new Plazmatic pad with an Alu backing that solves (what I feel) the problems of plastic backed pads (flex) AND solves the problems associated with the first generation Magura compatible Al backed pads that were made by Threshold. The disadvantage is that they need to be set up absolutely perfectly to get them to feel right. We'll also be producing a new hydraulic rim brake with some features that I think everyone will like. I promise that at least one aspect of Magura setup will be solved AND with loads more power.