ESW116

In what context? Road riding? Sure, they're more like a sidegrade rather than an upgrade. But discs weren't developed from road riding. Go into the mountain bike forum and say that discs aren't a MASSIVE improvement over previous tech.

tjspiel

I used to wonder why you don't see disc brakes more often on road bikes. Now that I have them, I know why.

The road BB7s are fine but not a revolution in braking performance, especially if your road bike is used mostly in dry weather. That said you should be able to skid the rear wheel. Cable housing is more important in rear brakes due to the longer cable run. Compressionless housing (the kind made for brakes) makes them feel a little less spongy and might help.

Rim brakes have a ton of leverage compared to discs, especially on 700c wheels. I can see though where on off-road bikes, discs would have an advantage. As tires get bigger and harder to clear, you need more massive brake hardware for effective rim brakes. Offroad bikes are also more likely to be ridden in mud and in other conditions that favor discs.

CabezaShok

Quote:

Originally Posted by ESW116

In what context? Road riding? Sure, they're more like a sidegrade rather than an upgrade. But discs weren't developed from road riding. Go into the mountain bike forum and say that discs aren't a MASSIVE improvement over previous tech.

Plenty of MTB'ers still run Vees, they are lighter, cheaper, easier to dial-in, and simple to repair out on the remote trail. I use XTR V-brakes, Avid Speed Dial levers and a rear brake booster. Our trails are dry dessert type, but if its wet i can always change the pads. V-brakes are perfectly fine for dry XC trails....Id be happy to use discs, if i lived in snow/mud/downhill mountain country where id see a "MASSIVE improvement"...horses for courses.

spare_wheel

I have BB7s on my 7.9FX fork and on my 94 stumpy shopping bike. And while mechanicals are an improvement over rim brakes, the shimano hydraulics on my orbea diem are simply on another level. If you are running a flat bar and can afford hydraulics I would not give mechanicals a glance. And BTW would sram and shimano stop teasing us and release their fracking brifter hydraulics already!

cyccommute 

I only have mountain bikes with hub mounted disc brakes. No, they are not a MASSIVE improvement. I obtained my first disc equipped mountain bike in 2001 but for 18 years before that I ran cantilever and then linear brakes (which I currently run on one bike). Neither disc nor linear brakes are that much of better than a set of properly adjusted cantilevers (which I still run on 3 bikes). Using the yardstick that is used here, I can skid the tires on my canti equipped bike. That must make them good!The hardware is less important than the technique, especially when riding off-road.


The idea that disc work better in the wet neglects to take into account that the tires don't work any better. It's even worse with ice and snow. Sure they don't get frozen up as badly but the very last thing you want in slippery conditions is something that can stop the wheel but not stop the bike.

ItsJustMe

If I was riding only in dry weather I wouldn't bother with discs. However, in wet, and especially in icy weather, they're nice.

I put mine on after one day when I was riding in freezing rain and had basically no brakes.

whitecat

Oh but you said that is where superior technique gets ahead. Surely you can manage a bit too strong of a brake with such a riding technique?

On a more real note, I like to have stronger reliable brakes especially in bad weather. And I‘ve ridden SD7‘s in rain with the supposedly best pads for the rain - result was - braking was like trying to stop the train, slow to react, slow to scrub speed, and ultimately, simply inadequate. Coolstop, Swisstop, and a number if other pads that were used - a pure waste of money. Yes, the brakes looked nice, but that was about it, no real use in bad weather.

And, for fast and agressive riding in urban enviriment, among cars, right hardware is imperial. That is, if you want to live.

Andy_K 

I've used both MTB and road version of the BB7's (yes, both paired with the correct levers). In my experience, the mountain version does feel more powerful, but the road version is still better than the rim brakes I've used (caliper, cantilever or linear pull). It's not day-and-night better, but it is better.

fietsbob

If you tighten up the brake pad to rotor clearance to the absolute minimum,
you also probably could fling yourself over the handlebars, too..

pasopia

It sounds like a problem with your setup.

I recently built a soma double cross with avid road bb7s, and Tiagra brifters. The brakes are great, and noticeably stronger than any canti I've used (avid shorty, tektro oryx, tektro cr720, shimano br 505). They don't grab as fast as v brakes with the matching linear pull road levers, but the modulation is better, and they can stop me just as fast.

I am using compressionless housing and normal brake cable. One thing I noticed early on, was that turning the inline barrel adjuster on my housing a bit to tighten up the cable slack really made a difference. At first I set the brakes up with the pads as close possible without rubbing, and did some riding without messing with the barrel adjuster. I had to squeeze the lever a bit before the brake started catching. I turned the adjusters to tighten the cable until just before the pads rub, and the brake grabs much sooner now.

I would try reinstalling the brakes on your own, following these instructions https://howtosetuptheavidbb7.weebly.c...-avid-bb7.html

canyoneagle

Certainly a valid point. However, from my own experience (yours may certainly vary), tire traction in the wet is not that much less than when dry, so the limiting factor that I've run into with rim brakes is a dramatic reduction in effectiveness when compared to my BB7's (I use 185mm G3 and XTR ICE rotors, for context). This is particularly noticeable with a loaded commuter - the bike alone is ~35 pounds with fenders, racks and such, plus another 15-20 in the panniers depending on the day. Since I know you're a sciencey type of a guy, you'll know that the added weight actually contributes to the friction/traction while simultaneously adding to the momentum. I know that speed contributes far more to the whole momentum thing, but my point is that I've found rim brakes to be the weak point in the wet, not traction.

In the snow/ice, I ride studded tires, which does help, though the differential is not as great assuming it is a dry cold. In those conditions, modulation is my best friend.

For mountain biking, I'd tend to agree with you (again from my own experience with my SD-7 V- brakes) because when conditions are wet, the added wet braking effectiveness of discs is pointless if the trail is slick.

cyccommute 

Imperial? As in suggesting an empire or emperor? Or does it have something to do with the British Empire or the Russian Empire or the Empire of Japan? Maybe it's of a particularly large size. Or are you thinking of cinnamon imperials? Are you perhaps referring to something to do with the British system of weights and measures.

If you are saying that the right equipment is imperative for fast aggressive riding, I'd agree but I don't look on discs as being imperative. I ride fast. I ride aggressively. I do both in all kinds of weather. I just don't see hub mounted discs are being much of an improvement.

Makeitso

Never used disc brakes on a road bike before. I have BB7's on one of my MTB's and they work way better than any other brakes I've ever had on an MTB. They work so good I have to be careful when I ride the road bike or the other MTB because I have to grip the brakes so much harder to stop. The other MTB has v-brakes on it.

The disc brakes do make noise now an then but it's not a big issue.

Like others have said, you're setup must be incorrect or the road version just isn't as effective.

SnowJob

Yes, it should be set up properly, but if his brakes have that little power, something is very wrong. BB7s don't need much hand force at all to lock up both tires. If he is squeezing as hard as he can and cannot lock up the rear brake, then something is wrong with the setup.

Bully for you for getting good power out of cantis. I haven't really had a canti equipped bike since I sold my old Rockhopper about ten years ago. The last bike I purchased that had cantis, I removed them and threw on mtb v-brakes. Cantis, in my opinion, have very little power and do absolutely nothing when it's wet out.

SlimRider

I think that after all of the favorable testimonials given here, in addition to all of the positive BB7 reviews, we can all safely conclude that, if the BB7's are properly installed and set, they'll make for very effective brakes. That's especially so, if compared to other mechanical brakes when stopping under wet conditions.

References:

https://www.bikeradar.com/gear/catego...rotor-10-37621

https://howtosetuptheavidbb7.weebly.c...-avid-bb7.html

https://www.singletracks.com/mtbrevie...d/BB7/783.html

SuperDave

Idle question, since we're talking disc brakes: Has anyone ever used the anti-squeal compounds provided with automotive disc pads (or available aftermarket) to silence the squeal? Since the design is essentially the same on bicycle discs, I would imagine that the cause and solution is the same as well.

For the record, if I owned a bike which couldn't lock up either wheel with one finger of force, I'd change the brakes instantly. I can do one-finger stoppies with the cantis on my Coda; the only reason I'm going disc is for bad weather. That, and I dropped $300 on the front wheel, and I'm darned if I'm just gonna wear it through with brake pads.

AdamDZ

You're not supposed to put anything on bike disc brakes. Car brakes apply exponentially greater forces so the physics are slightly different.

SuperDave

Makes sense when I think about it. The vibration frequency would be a whole lot higher, as well.

cyccommute 

pkulak, although whitecat might not think so, I am open minded enough to be open to suggestions. After following the instructions on the link that pasopia provided, I was able to get my BB7s to act more like a good linear brake than like a 1980s Chinese knockoff Mavic center pull. You may not know what that kind of brake is but it was best if you planned ahead for any stops you had to make. The best strategy to use was to tie the cable to a tree and then ride for 3 miles. At the end of the 3 miles, the bike would slow down. It wouldn't stop...you needed 10 to 12 miles for that...but it would make the impact with the object you were about to hit a little less painful.

The instructions are pretty good and I like the way that he uses to center the brakes better than anything else I've tried. I won't admit that the brakes are better than anything I've ever used but they are much better. Avid's set up simply sucks.

MileHighMark

You meant Mafac, right?

Also, if you're running the road version of the BB7 (with drop-bar levers), "wind up" the actuator arm slightly before you tighten the cable fixing bolt. Ignore the part of the instructions where they say to leave it fully open/relaxed.

drbenjamin

Since we're covering a lot of topics on BB7s I've got a question for the crowd:I commute year round in Seattle, and put a cyclocross fork w/ BB7s on my road bike. Huge improvement in the winter, it's really no contest. My rims get covered with a fine abrasive paste, and while I can scrub it off by tapping a rim brake repeatedly sometimes I need my brakes NOW not in 20 sec.Anyway, today we had a rare sunny day. I went for a ride and was coming down a 1200 foot hill with grades 14-20%. The brakes felt fine the whole time, but 2/3 way down I got nervous, pulled over and sprayed a little water on the (stock) disc. The water instantly turned to steam. So my question is, how much heat can these things take? Do they fail catastrophically or do you get some warning? It would have really sucked to lose brakes on this descent.

sirtirithon

Sorry for asking a simple question.

ESW116

They're designed for it. They will only "fail," I suppose if you hold the brake constantly. You could easily keep yourself steady by applying firm intervals of braking rather than constant pressure. But realistically they won't really fail. They'll just become too hot and lose efficiency at which point they would need to cool.

AndreyT

I switched from road BB5 to road BB7 relatively recently. When I first installed BB7 they felt very mushy. I also couldn't lock up my rear wheel. However, after carefully realigning them in accordance with manufacturer's instructions I made them work. No problems ever since, aside from occasional squeal.

I agree with previously posted advice: keep the brake actuator arm slightly pre-tensioned (despite the manual recommending to leave it fully relaxed).

AdamDZ

Yup. They'd have to turn red to fail catastrophically Don't worry about that.

If you're using the right levers with BB7s and have set up the pads and cables properly then there won't be any need for that.