Why Magura rim brakes?


I know that the disc revolution is upon us, but hydro rim brakes are great performers and can be mounted on most unicycles in about 20 min.

Though it might not be news to many of you, See my brake post in the trading post if you are interested in magura rim brakes. . . . Cause I do have like . . Lots of rim brake options here or you, new, used, parts or just bleeding help.

cheers, Brycer1968

A correctly set up V will own a disc or magura any day of the week, especially with such a short cable pull as well, but like has been said you can get problems if the wheel is out of true. If you’ve got the brakes available though stick a set on!

He has square taper cranks, cant use isis spirt cranks

Maguras are still plenty good, I’d like to try a disk brake just so I can feel the difference but I know that my magura does the job. Even if they’re old, it doesn’t mean they’re bad. I’m still riding the same brake I bought from Brycer1968 three years ago.

Also, I have a huge dent/6"long flatspot on my rim, I got used to it :stuck_out_tongue:

Kinda with the rim out of true thing, I keep my rim super true so it kinda helps keep all my stuff up kept nice

Original Question: Why Maggies?
If you look back through the forum it is pretty clear that Maggies became the standard as the tires for MUni got wide enough to make caliper brakes useless. Once the tire hits the caliper, or wire you’re done.

Maggie’s are great brakes, but not without problems.

On my Nightrider frame I had maggies and found that I couldn’t get them far enough away from the rm to eliminate brake drag during mounting on a grade. The Nightrider is a pretty flexy frame, and when you are mounting uphill it’s really hard to mount without having the maggie stop the wheel. It did teach me to do a better rolling mount.

I then went to V’s, and they were really nice. Super easy to adjust the gap so that my rim didn’t rub. A benefit I wasn’t planning was that they didn’t stick out from the frame as much as maggies. They were pretty grabby when I first set them up, but after toeing in the pads a bit more than normal I had really nice, quiet, modulation. I prefer V’s to Maggies if I can swing it. I still have Maggies on my MUni due to the tire volume issue. I have started running a narrower tire, so maybe V’s will work on that, but for now I think the Maggies will stay.

I then went to a disc brake on the 36 (square taper crank mounted disc). The disc was the best of the lot. Frame flex is a non issue. The brake has such a small rotor that modulation is king. If you think about it a rim with a standard brake is pretty much a really large rotor, by making a smaller hub mounted rotor you don’t get nearly the leverage, so much better modulation. I really only use the brake for long sustained descents, so I had the caliper hooked up to a shift lever to use as a drag brake. If you can find a cable disc caliper that will work inside the tight clearances on a uni it is a nice way to go.

Exactly - no way I can use disc brakes. Even if there was a way to fit them to my hub/cranks, I have an original Schlumpf frame with non-standard bearing holders so I couldn’t fit a D’brake (and before anybody suggests getting a new frame, the hub has non-standard ~90mm bearing spacing!)

OK, so clearly I phrased my subject ambiguously - I wasn’t wondering why Magura rim brakes rather than discs, I was wondering why Maguras if you were using rim brakes. Thanks to all those who’ve answered the question I was trying to ask - this is going to be a road uni, or if I take it off-road I won’t be fitting a huge tyre, so no problems with clearance, so I’ll fit the V-brakes I have then. As mentioned, the frame comes with V-brake mounts rather than Magura mounts so not even any need for adapters.

The only remaining issue is that it currently has a disc only rim, so I need to find a 36h 29er rim which can be used with rim brakes (well that or upgrade to a bigger rim, but I don’t think I’m ready for a guni 36er yet - maybe a 32 if anybody has a spare or knows how to get one cheap in the UK?) I don’t think the standard uni rims will work as they’re all a bit wide to work with the brakes - the spacing between the brake mounts is only a few mm wider than on my bikes - though I’d prefer a narrower lighter rim anyway.

Loads of MTB 29er rims on chainreaction in 32h, not sure if they’d be strong enough though

Loads of disk brake 29er rims you mean. Anyway, as stated I need 36h to go with a Schlumpf.

How wide are we talking?

SINZ square taper will fit your 1st gen Sclumpf

Aracer, Attached is a pic of a square taper SINZ with original prototype disc ( since changed to multihole-pattern and eliminated dual hole mods). I don’t see a reason why you couldn’t use this design with your square taper Schlumpf. Without recalling your frame application off hand, I also have steel tab mounts that I could include which would eliminate the need for a UCM mount. Some of the more seasoned veteran forum posters want to guide you toward new hubs, but it can be done with any square taper design, including Coker retrofit’s with a UCM.

Oops with pics

Rotor & Dual Hole Cranks.jpg

COKER 36.jpg

Depending on the crown and existing mounts, a cable actuated brake is the easiest to set up, least cost also, esp since this is an older Schlumpf and is only being used on the road.

But you have a disc only rim, are you sure?? That seems strange to have a disc only rim on an older wheel build, maybe it just doesn’t have a machined sidewall? Unless it’s very slanted on the sidewall, you can possibly make a brake pad work depending on the brake reach.

Rebuilding a wheel is no hard, just find an inexpensive 36h hoop.

Fom MTBR, circa 2007: 36hole, 29"

Velocity Blunt (480 grams)
Velocity Dyad (480 grams)
Velocity VXC (460 grams)
Salsa Delgado Race (455 grams)
Salsa Delgado Disc (500 grams)
Salsa Delgado Cross (460 grams)
Mavic Open Pro (425 grams)
DT Swiss TK7.1 Trekking 700c (540 grams)
DT Swiss TK7.1 29er Disc Rim (540 grams)
Mavic A719 (565 grams)
Mavic A317 (538 grams)
Mavic A319 (597 grams)
Sun Rhyno LIte (599 grams)

Not sure which of the above have a sidewall for rim brakes…

Also look for Tandem rims, maybe an older KH rim?

Alex Adventure Rim if you can find one

Sun Ringle Rhyno Lite is an old standard

Thanks for the info, Ben. Apart from needing a new rim, the V-brake is pretty much zero cost as I already have all the parts.

It’s a tn719 which definitely won’t work with a rim brake - has a very slanted sidewall. I think the hub’s been rebuilt a few times to try out different wheel sizes, so it’s an old hub, but a fairly recent wheel build, and presumably the original owner didn’t envisage needing brakes. No worries about rebuilding - I built the wheel on my 19er myself and rebuilt the wheel on my unguni 29er when the spokes started snapping. In fact one of the main things prompting this thought is that I’m going to rebuild the current wheel as I found some of the spokes had gone completely slack, and then decided I might as well sort out the spoke pattern whilst I was at it (the valve hole is in the wrong place in the spoke pattern, and on one side the spokes are in the hub the wrong way - the spoke holes are only chamfered on one side on a Schlumpf). Will rebuild on the current rim for now as I want to ride, but looking at options to rebuild so I won’t put huge amounts of effort into making it perfect.

I’m seriously considering an Exal ML21 http://www.spacycles.co.uk/products.php?show=1569 as it’s that little bit wider than anything else I can find - I’m sure my brake mounts will cope with that, just not with much wider. Though it is rather heavier than the 19mm wide (internal) alternatives, if still a lot lighter than wide uni rims. I guess 19mm wide is fine for road use, and I’m not really likely to take this off-road that much - it would just be nice to have a bit more support for a widish off-road tyre to try occasionally, and I’ve seen good reports on that rim for strength, so the only real downside is the weight.

Oh and interesting thought on the Sinz disc cranks - hadn’t realised you could get those in ST, and the 135mm crank length would be interesting if that’s available in ST as I currently have 140 but nervous about going down to 125 (though on the downside I’m not sure I ever would have the option to go to 125, and changing crank lengths would be an expensive business in general).

Though we still come back to the issue of caliper installation - it’s an alu frame, so braze on steel mounts are no good, and I’m pretty sure a UCM wouldn’t work as the bearing isn’t centred in the mount.

Bit pricier but there’s a few options here http://www.billys.co.uk/english/productresults.php?dept=565&group=B&PHPSESSID=kffk2fl6uic37gaes4gicmq6q4

135mm SINZ Square taper is available, and understood on the aluminum frame. The bearing cradle on UCM is centered, but your saying your frame would require an off-center mount?

yes, the old schlumpf frames have off centerd frames.

How did you mount a disk brake to a square tapper hub?

How did you mount a disk brake to a square tapper hub? Contact me at Richarddtharrett2019@gmail.com