Hs33

[BIGA1]

Why would only one of my brake pads move when I pull the brake.

PLEASE PLEASE HELP ME.

[ted]

Why would only one of my brake pads move when I pull the brake.

PLEASE PLEASE HELP ME.

Were the brakes on the bike when you tried this? The cylinder might just be a bit stiff, in which case when one pad touches the rim the extra pressure will force the second to move.

[JT!]

You have a lazy piston...

One of the main problems to occur with maguras is known as a ‘lazy piston’. This means that only one of the pads seems to move, and one pad seems to just sit up against the rim just skimming it. The reason for this is because you have too much TPA. If you undo your TPA right off, you will see both pads retract normally. If you do have a lazy piston, you need to re-setup your brake like instructed in the next paragraph.

The better you set up your maguras, the better they will work. If your re-setting your maguras up, undo the bolts on the clamps and remove the brake completely, make sure the large plastic washer are all intact, if they’re chewed up, it can cause problems later on.

The next thing you need to do is undo your tpa right out. This is important especially if your having lazy piston troubles. You need to undo your tpa so that the pads retract right back. You know when you have reached this point when you can pull the leaver down and it isn’t actually pushing an fluid though, this is because the pads can not physically more any further back. Now is a good time to double check you wheel is straight (if you have horizontal dropouts anyway). What some people do (including myself) is realign the wheel rather than adjusting the maguras. After doing this a few times your wheel can be at any weird and wonderful angle without you noticing.

Now, to put the brake back on. Do one side at a time. First, place the underside of the clamp down. The place once side of the Magura on top of it, but have the brake pad pushed right up against the rim. The reason for doing it like this is that it’s easier to move the brakes out, than move them back in. Also, it gets it in a good initial position. After you’ve done that, place the top part of the clamp on, and screw it down. When screwing the bolts in, try and screw them in evenly. If you screw one side right down, and then the other, your putting a lot of extra strain on the other bolt, which isn’t good where threads are concerned and how easy they strip.

Screw them down so it holds the cylinder firm, but so you can still move it about. Then you simply wiggle the cylinder back, you can actually pull the leaver to help move the cylinder back if you need to. A good guide to how far you need to pull it back is that you should just be able to put a 2p coin between the brake pad, and the rim. Once you have got it the right distance back, rotate the cylinder round so all of the pad will hit the rim, and that the surface of the pad will sit flat on the rim. Once you have it perfect, slowly tighten the bolts up, remembering to tighten them up evenly. Keep your eye on the position of the pad, and make sure it stays in the position you’ve just set it up in. Tighten the bolts down firmly, but be careful you don’t go over the top, it can damage the threads in the frame.

Now that you’ve done one side, do the same for the other side.

Now all you need to do is adjust the tpa to how you like it and there you go. It is difficult to do first time, but the more you do it the easier it will become. There are a lot of different techniques to setting up your brake, so if you find a way that suits you better, stick with it.