I tried tacking this question on to a really old thread, w/ no response. Trying as a new thread instead.
I’m using the Magura hydraulic with a black Sun doublewide rim. I’ve seen several threads with discussion/comments around grinding the rim to reduce braking noise, but will this also serve to U]increase grip?[/U] And if so, what level of grinding is required…should the goal be only paint removal, or is some level of roughness on the rim also desired?
While I’m definitely getting the noise, that’s not so big a concern. The bigger problem is I can’t really get any serious level of grip, even with the handle adjustor maxxed out. It came that way out of the box, which amazed me for something so expensive. The response I got from unicycle.com was this was due to the painted rim, hence my question around grinding.
I haven’t yet tried anything around adjusting the pads or that part of the unit. Figured I’d ask advice first before starting a random troubleshooting exercise.
The Magura brakes are good quality; it sounds as though the setup may have slipped some. This shouldn’t happen during normal riding. And, of course, the rim was not designed for rim brakes.
If you are comfortable adjusting brakes, simply follow the Magura instructions that came with the brake (did you get instructions?) for adjusting them. Your local bike shop, especially one that is good with mountain bikes, could do it as well. Tell them to toe-in some (Maguras are designed not to be toed-in), unless you are using the brake like a trials brake. If you are using the brake to lock-up the wheel, for hopping and the like, then use no toe-in the way the instructions say.
You can also get the Magura rim brake installation and adjustment instructions on their website:
The easiest way to increase stopping power is to change the brake pads. Black,grey are the standard brake pads. Green has a little more grip and red has the most. If you really want to stop quickly, Plazmatic makes pads for Maguras and they’ll get you stopping.
Generally the better the grip the louder the brakes are.
Before you start buying pads set up your brakes again. Make sure the pads are all the way in so that you can adjust them as the pads wear out.
I haven’t tried to make a Doublewide rim brake friendly so I’ve been waiting for someone who has direct experience to reply. But they haven’t. So…
The solution I’ve seen for the Doublewides is to sand off the paint along the sidewall of the rim. Just get rid of the paint where the brake pads rub. I haven’t seen anyone try to roughen up the braking surface with a grinder. I know the trials bike guys like to roughen up the braking surface of their rims, but I don’t think that’s what you want on a unicycle because you don’t want things that grippy (instant face plant).
Sand off the paint smoothly and then experiment with differnt brake pad compounds to get the grippyness that suits you.
Trialsin.com <http://www.trialsin.com/> is one place that sells different brake pads for the Magura brakes. A local bike shop that is familiar with trials bikes would also know about the different brake pads (unfortunately I don’t know of a LBS in the Seattle area that does trials bikes).
Good advice…will try light sanding first before pulling out the grinder.
I’m still just experimenting, trying to get the hang of the brake in general. So far, I’ve found that my face plants haven’t come from applying the brake, but rather once I’ve acclimated to having it on and then my fingers slip off the lever and it releases suddenly before I can compensate.
The first time I tried mine (on the Coker) was on a country road near the house on the back side of a small hill. I went about 12 feet horizontally through the air and landed on my feet. The normal bike squeeze had kicked in.
I have little experiance with brakes, but what I do know is I wouldnt want a ground braking surface, especially for steep DH or short hills on a coker. I would have to agree that simply anding the paint off the side is a good start, and if you really need more stopping power from there, get different pads. Almost any shop should be able to order at least a few different magura pads, as QBP sells at least 3 compounds, I think.
magura breaks are by far the strongest rim breaks available. i kinda like the
fact that they come pre-set up and blead. you might need to adjust the pads for
better contact. the sun ringle’ doublewide is designed for disc breaks. so if
pad adjustment dosen’t cure it then I would grind the paint off. Also, some
times the pads need to be broken in. with some breaks obnoxious squeeking cant
be helped some people accualy like it it kinda lets them know that their breaks
are working.