disc brakes for cross
Last Post 02/23/2014 04:23 PM by Kenny Gonzales. 55 Replies.
Author Messages
Oldfart

Posts:480

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11/12/2013 03:29 PM
Looking at race photos it seems that most of the North American pros are using disc brakes whereas most of the European pros do not. Some of the Euro's are testing them in races but cite weight as a disadvantage but some of those guys do also say they like how they actually work in crap conditions whereas rim brakes do not.

I have ordered a Giant TCX Advanced so I will get to see for myself if it ever shows up. The SRAM recall may have buggered arival time up. Apparently the arrival time was posted on the dealer site but that ETA has disappeared concurrent with that recall. No one seems to know what the recall is about though.
THE SKINNY

Posts:402

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11/12/2013 04:08 PM
laars van der haar was the only one of the top guys riding them in the last race i watched.
How we spend our days is, of course, how we spend our lives.
jmdirt

Posts:704

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11/12/2013 04:20 PM
A guy named Nys uses and likes them as well. He said that not only are the brakes slightly heavier, but the frames are also heavies to strengthen the caliper mounting areas. He plans to use disc on sloppy courses without much bike lifting, but use cantis on courses that require lots of bike hefting. I wonder if he considered rim weight? Most disc rims are lighter.
THE SKINNY

Posts:402

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11/12/2013 05:01 PM
i haven't seen nys use them yet but i haven't been religious about watching the races.
How we spend our days is, of course, how we spend our lives.
Oldfart

Posts:480

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11/12/2013 07:31 PM
Yeah Nys and another top guy ran them for a few laps during the last race.
dkri

Posts:80

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11/12/2013 09:09 PM
I predict that this year's worlds will be won on discs and rim brakes will be an afterthought thereafter. I will also be the smarmy d-bag who points out that this has happened approximately absolutely exactly how and when I've been saying it would for the past several years.

From the participant/rider side, I think the differences are splitting hairs and there's not that much benefit or cost to either choice. From the gear supplier side, you'll have one or two holdouts making nice Canti frames (Van Dessel will be one - Edwin Bull vocally opposes discs) and everyone else will wholesale switch to discs.

Bad discs will continue to be worse than good rim brakes, and good discs will get better and better. As electric shifting takes over, shutting and braking will decouple from each other inside the mechanism. There will be hydraulic brake pods with shift buttons on them.
formerly dkri
THE SKINNY

Posts:402

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11/13/2013 08:53 AM
the race i watched yesterday evening, nys other bike had disks. it was a super sloppy course.
How we spend our days is, of course, how we spend our lives.
Master50

Posts:233

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11/13/2013 08:13 PM
there is still a problem with rotors and sloppy courses wearing out pads before the end of the race. Most rotors seem to trap the mud in the cooling holes. there are a couple of rotors that don't do this but they are uncommon.
the first 2 world cups were won by Van de Haar on a bike with disks
Oldfart

Posts:480

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11/14/2013 03:52 PM
Part of the wearing pads problem was with mechanical disc brakes that needed more adjustment than they had available at the barrel adjuster. Some of the problems are with the use of organic or resin pads which most mountain bikers around here where it is wet and muddy more than half the year know are fast wearing things. Metal pads will help that a lot. Some muds are grittier than others too. And some say using a solid rotor would help a lot as well. All those little holes collect and trap grit.

One of the local shop team guy's has had a problem with one of his SRAM disc brakes wearing fast. He thinks it is a lazy stuck piston that rubbed a lot during one race. The other two riders on SRAM disc brakes have not had that problem though. All are on organic pads as far as I know because the metal pads have not shown up yet.
Hoshie

Posts:114

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11/16/2013 02:46 PM
It's here...good deals this year on canti frames as those get blown out. I had my cantis adjusted and am a bit happier but better brakes are a plus. Most of our races are dry and fast so although I'd like discs, it's not so critical for our style of courses.

Thought about switching but I'd need brakes, a new disc compatible fork, and new wheels so plan to wait until its new bike time. Probably move to trp v brakes after cross season is over.

I think most or all the pros will move over to discs within 2 years or so as the next wave of improvements occur.
6ix

Posts:121

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11/16/2013 05:36 PM
Here is my point of contention with discs. Although thru-axle helps a LOT, the pads rub the rotor because there is so little room for error. Why can't the pads be pushed out further away from the rotor? I don't understand this. At least with road calipers you can open the brakes should you have a bad rim.

I've spent a lot of time adjusting my hydraulic discs on my mountain bike. Fortunately, I have thru-axle and for the most part, they don't rub. But my wife's C'dale doesn't have thru-axle and I've never successfully adjusted those darn brakes to not rub. They don't seem to be very user-adjustable. I typically feel confident working on my bikes, but not if it includes bleeding hydraulic cables. That's where I throw in the towel.

Roadies will NEVER fully adopt discs until they can resolve the issue of pads rubbing if the rotor is off by a millimeter. There needs to be more wiggle-room.
gabbard

Posts:27

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11/18/2013 10:14 AM
DKRI,

What do you consider good and bad disc brakes?  I test rode two disc brake cross bikes over the weekend - Specialized Crux with Sram hydraulic disc brakes, and Ridley X-Fire with Ultegra mechanical disc brakes.  The Crux stopped liked I thought disc brakes should - fast and consistently.  The Ridley cable brakes were much worse than my TRP mini-V brakes on my current cross bike.  I couldn't tell if this was a pad issue, a setup issue, or simply related to the overall design.  My Avid mechanical brakes on several MTBs stop really well (not quite as nice as hydraulic, but way cheaper), so I am curious why the Ultegra brakes were so marginal.

As I start to consider a new cross bike, I am bit worried about buying in to the wrong type of system - SRAM hydraulic vs mechanical - and I am not totally psyched about SRAM road gear, having always used Shimano components.

Any thoughts?

Steve
dkri

Posts:80

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11/18/2013 04:07 PM
Steve -
Mechanical with road levers, IMO, are pretty bad. Mechanicals with road levers don't have enough pad throw to avoid either rotor scrape or over-sensitivity to pad wear. Your experience was right in line with what I would have predicted. I had BB7s on a mountain bike for a couple of years and they were great. Nowhere near as great as the X.9s I use now, but pretty darn good. BB7s on a cx bike with road levers? I'll pass.
Shimano makes very very good stuff. Avid brakes take a lot of guff but I've had great luck with them.
Dave
formerly dkri
pabiker

Posts:80

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11/18/2013 09:32 PM
I pretty much NEVER adjust the pads on my mt bike. I ride in horrible terrain that destroys bikes and gear. If you are spending "a lot of time adjusting pads on your mt bike" you are clearly doing something wrong.

Adjustment would be even more infrequent on a road bike because how would you EVER bend a rotor on a road bike? On hydraulic disc brakes today in lieu of a bent rotor you NEVER have to adjust the pads.

Even if you did, my SRAM (AVID) levers have a pad adjustment knob (which I NEVER) use.
gabbard

Posts:27

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11/18/2013 11:18 PM
pabiker - I am not sure if you are responding to my comment, but I am trying to figure out where someone said "a lot of time adjusting pads on your mt bike". Also, my application would not be for a road bike, (don't see a need for disc brakes there), but for a cross bike that will be used on trails. Not rough trails, but going fast on moderate trails can kick up rocks, so maybe a rotor would get bent. Never had a disc brake cross bike, so this is a new world.

dkri - Shimano makes good stuff, but I don't yet see that they make a hydraulic lever with a corresponding road hydraulic brake, or at least the bikes I have test ridden didn't have that option. I agree with you - my BB7s work pretty well, but I much prefer my Avid hydraulic brakes.

The whole disc brake - road wheel situation is evolving rapidly, maybe I need to wait another design cycle and see how it all shakes out.

pabiker

Posts:80

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11/18/2013 11:40 PM
see above.

I would use disc brakes on any cross bike without hesitation. Kicking up a rock doesn't bent rotors they get bent by running into or side-swiping a rock that doesn't move.

Again, hydraulic disc brakes today don't need to be adjusted. That is, unless you fooked them up.
jrt1045

Posts:361

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11/19/2013 08:55 AM
if you by Avid you better be familiar with your bleed kit, the idea of SRAM selling integrated brake/shifter combos would is enough to send me scurrying for something else. Everything I have encountered from SRAM, brake and drivetrain wise has been junk. Road and mountain, can't believe they get away with selling it. Compared to Shimano it is poorly manufactured and executed at every level. If Shimano came out with something hydraulic for road/cross I would be interested, SRAM - no way

FWIW: I have a set of XT's that I pulled out of the box and installed 2 years ago and have done nothing but replace the pads now and then. Like PA, I ride in an environment that eats bike parts so think that is pretty good. For the record, the only rotor I ever bent also destroyed the wheel

As far as rotor rub, centerlocks. Biggest problem I see is having to true a perfectly straight rotor around the 6 contact points of a hub. Centerlocks and thru axle? - magic

Back to point of the OP, I see disc as a very viable option as long as they are made by someone other than SRAM
dkri

Posts:80

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11/19/2013 08:58 AM
PA and I agree for the most part, except I wouldn't choose to use mechanical discs on a cx bike. I did it for a season and didn't like it. Lack of pad clearance is the issue. Your rotors need to be hyper true to be able to set them up without rub, and with QR wheel attachment your hubs can shift the tiny little bit needed to cause rub. Rotors can come out of true by being bent or being warped. Stream crossings or puddles at the bottom of hard descents pose a risk for that.

I've got probably 50 hours on my mountain bike's X.9s without doing any adjustment. On BB7s with road levers on a cross bike, I don't think I've ever made it through an hour without some small adjustment being necessary.

**edit after reading jrt's post - I've had better luck with Avid brakes than apparently anyone else, with 3 years on them with no issues, but I bled them all at the outset.  I've also apparently had worse luck with bending rotors than anyone else because I've got a pile of bent rotors, bent in both cross and mountain bike use.**

Talking about "discs" almost needs to be cut in threes - hydraulics ("hooray!!"), mechanicals with mountain levers (slightly less enthusiastic "hooray") and mechanicals with road levers ("boo hiss" in my experience).
formerly dkri
gabbard

Posts:27

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11/19/2013 09:17 AM
So, if you are looking at hydraulics on road levers, what are the options? It looks like SRAM is the only integrated option. TRP makes a hydraulic, cable actuated brake, but is this the worst of both worlds? Would the recommendation to be to go with SRAM shifters and brakes, or wait until Shimano comes out with hydraulic road brakes? I don't like the option of buying Shimano mechanical brakes, only to change out levers and brakes in 1-2 years.
longslowdistance

Posts:680

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11/19/2013 09:30 AM
Regarding the TRP cable actuated hydro, I've been using one on an adventure bike for a few months with a Shimano ice tech rotor. It is an improvement over the Hayes CX mechanical it replaced in terms of feel and power, but haven't had a chance to truly challenge it on a long steep descent. I have no personal experience with dedicated road hydros so I can't compare with what should be the current gold standard.
Dale

Posts:487

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11/19/2013 11:38 AM
Posted By Steve Gabbard on 11/19/2013 09:17 AM
TRP makes a hydraulic, cable actuated brake, but is this the worst of both worlds?


Best of both worlds-- lighter than full hydraulic, cheaper levers; important when racing cross where levers get whacked and you're not a sponsored rider
Oldfart

Posts:480

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11/19/2013 04:14 PM
Gabbard: Shimano has a set of hydraulic cross/road brakes too but it is only DI2 which means you need the derailleurs too.

I think some of the issues some people have had with keeping a rotor centered has to do with the hub end caps or lock nuts not being perfectly square. I had that issue with XTR hubs which were and still are cup and cone. I found that every time I took a wheel out and put it back, the rotor was no longer centered. I also discovered that if I marked the position of the lock nut with a reference dot on the frame as well that I did not have that problem. This was with standard qr axles. Never an issue with DT hubs or with through axles. I like that Giant has made their cross forks with a 15mm qr and mountain spaced hubs.

I am a bit leery of the SRAM kit because their hydraulic mountain bike brakes are not easy to bleed and some of their brakes howl like a banshee no matter what you do. I know this from experience with numerous Avid brakes. They do function well from a feel and power perspective but the last pair of XO brakes needed to be bled every three or four months. My Shimano brakes maybe one a year.

I have read a cure for the howl is as easy as applying tape to the back of the brake pads. The adhesive on the tape provides a gummy sort of damping effect or so i have been told. I sold the bike I had that squealed like Ned Beatty.

http://www.youtube.com/watch?v=WqNMjZpSbnU

pabiker

Posts:80

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11/19/2013 05:45 PM
My comments are entirely about hydraulic disc brakes. Why anyone would use mechanicals at this point is confusing to me.
longslowdistance

Posts:680

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11/19/2013 06:08 PM
PA, here's the scenario: Because the bike in question is a road bike and the rider already has $400 invested in brifters.
dkri

Posts:80

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11/20/2013 09:09 AM
^^ what he said. In one case (SRAM) you need an entirely new mechanical drivetrain, in the other (Shimano), you need an entirely new electronic drivetrain. Paraboxes are dead ends. The mech-to-hydro TRP things are your only hydro solution that doesn't require a new drivetrain. Seems like a pretty profound barrier to hydros to me.
formerly dkri
Cosmic Kid

Posts:1113

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11/20/2013 10:12 AM
The success of discs in cross will lie in OEM spec, not so much in people converting. As racers / riders want new bikes, hydro discs will become more prevalent, IMO.
Just say "NO!" to WCP!!!!
gabbard

Posts:27

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11/20/2013 10:38 AM
I learned something new - I didn't even know what a Parabox is.  Even after googling it, I can barely figure out what it is.  Some sort of stem mounted box that converts cable pull to hydraulic pressure?  Seems like the TRP Hy/Rd has replaced it, and at $470, it is a good thing.

Just from looking at that device, with cables coming in and out, it is what we used to call a "frappus" at a previous job - a made up word for an overly complicated and expensive looking device, whose purpose or function is not clear just by looking at it.  Frappus performance is typically poor, and requires constant tweaking and tuning, with the end user limping along until someone comes up with a proper engineering solution.
dkri

Posts:80

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11/20/2013 12:47 PM
And "frappus" becomes part of my vocab. Anyone else remember Sniglets?

CK - since you pretty well need a new bike to convert...
formerly dkri
Cosmic Kid

Posts:1113

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11/20/2013 12:52 PM
It seems there is a fair amount of bikes form the alst year or so that were "disc ready" off the factory lines, but either used mechanicals or just had the tabs in place. This was similar to the MTB segment when discs were on the cusp of breaking through.
Just say "NO!" to WCP!!!!
jrt1045

Posts:361

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11/20/2013 01:57 PM
performance will come in steps and as CK said, OEM spec

ahh, the dawn of the disc age in the mountain bike world, brings back some memories. Road/Cross disc will probably be a similar journey. I really wanted to like the concept back in the day but it wasn't until I got a set of Hayes Mag hydraulics that I was satisfied with their performance. The road there was fraught with with a year or 3 of danger, confusion and re-reading the directions. but once headed in that direction there was no turning back. That road consisted of:

1) a cable actuated hydraulic front that was marketed by rock shox. similar to the parabox concept and worked like crap. couldn't even scare up replacement pads and I don't think I was ever able to bleed the caliper itself. a waste of a few hundred quid
2) 1st generation cable actuated, probably tektro. didn't work much better but simpler to set up and what not and much cheaper.
3) CODA - Cannondale pushed these during their heyday. 4 bolt rotors, some kind of crazy mineral oil. 1 piston or 2 piston - didn't matter as neither really worked. They were like no piston brakes In chronic need of bleeding, chronic BS from Cannondale engineers how that it was all my fault and my set-up that made them crap. How'd that moto x bike/marketing project work out? (stream of consciousness thought here). Might be the only brake I have encountered that was of worse quality than avids
4) Hayes, they worked - like really well. Simple, easy to work on and completely rebuild-able; many times with parts that can even be found at a hardware store. Genius. Fished an old set out of the parts bin and tossed them on my son's first MTB, worked like new after a few minutes of service

(I have had a lot of disc brakes, scary)

From there, mountain disc have generally improved with each new iteration. Road/cross will be similar, each new step is progress
Oldfart

Posts:480

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11/20/2013 04:16 PM
Yeah jrt. Pretty similar experience for me too. Those first Hayes Mags worked really well back in the day. Compared with what is available for mountain bikes today though they wouldn't be nearly as nice. Those Hayes brakes did a lot to change the way we rode our bikes in North Vancouver. Brakes that worked and worked consistently in all weather. Almost no maintenance required.

I think the change will be faster for cross because of what has been learned off road. I mean Shimano are using the Ice tech freeza rotors already. And I read somewhere that the calipers are XT which means one can use XTR race brakes if one so chose.

I have ordered a cross bike with disc brakes but I am not totally convinced that the braking difference will be as big a deal then it is with a mountain bike. It may be that after riding a disc brake cross bike a while that going back to rim brakes will reveal how crappy rim brakes really are. Sometimes going forward doesn't seem like much improvement until you back to the old stuff.
dkri

Posts:80

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11/20/2013 07:04 PM
The cx transformation is already way way further along than the mtb one was at the equivalent stage, at least in terms of xc racing. Discs were INVISIBLE in World Cup xc until after the '04 Games. Two seasons after they were made legal there have been World Cup cx wins on discs. As Oldfart says, they've already learned how to make disc brakes really really good, they just have to adapt them completely to cx bikes.

You're pretty far down the food chain at hermaphrodite cross bikes even since a while ago - many higher end bikes were offered as either, but very very few were offered as both. From all I see, cantis are gone for next year. It will be hard to buy a bike with canti setup.
formerly dkri
pabiker

Posts:80

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11/21/2013 12:02 AM
there you go again. mountain disc brakes are not "generally improved" at this point they are entirely dominant. there is no comparison in performance, reliability, durability; and if you are running anything other than hydraulic discs on your mountain bike at this point you are either (a) broke (b) don't care (c) a luddite (d) a moron.

Cosmic Kid

Posts:1113

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11/21/2013 09:05 AM
Well, the CX transformation is benefitting from the XC transformation. The path has already been blazed to some extent, so adoption is happening faster. This is true from both the industry and consumer perspective.

The industry has done this before and have learned from their mis-steps and consumers are more willing to accept the technology based on the MTB success.

That said, I disagree that it took until after the '04 games to see widespread acceptance in XC. I was spec'ing all discs above $1K back in '00 and was hardly a pioneer in that regard.
Just say "NO!" to WCP!!!!
dkri

Posts:80

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11/21/2013 09:36 AM
Read carefully - I said they were invisible in World Cup xc until after '04. Watch "Off Road To Athens," which was filmed in the build up to Athens. I don't know if you see a set of discs in that film. Widespread acceptance below World Cup level was years old at that point, as you said.

If World Cup cx were to follow a similar arc, Nys, VdH, Albert, and whmever else wouldn't have used discs yet. As it is, I'd say odds are better than 50% that this year's cx worlds will be won using discs.

I would agree with you and attribute this quicker adoption to the fact that disc brakes now work exceptionally well. The only substantive challenge is adaption to the cx platform. That's a much smaller problem than inventing brakes that work.

PA - if you read closely JRT said that discs "generally improved with each new iteration," not that they are "generally improved."

formerly dkri
longslowdistance

Posts:680

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12/08/2013 09:27 PM
Another voice has chimed on on the TRPs: retrogrouch randonneur engineer Jan Heine of Bicycle Quarterly really, really liked the TRPs (for road riding) - he found them better than the best rim brakes both in terms of power and feel. And he's never been a fan of road disc brakes -- he has consistently panned BB7s. So the rave review is impressive.
For me the fade/boiling question during sustained braking remains. Heine didn't ride a 5 mile sustained 12+% very twisty descent in warm weather, which I do from time to time. That's a lot of heat loading. Won't be until next spring that I can try this for myself.
jrt1045

Posts:361

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12/09/2013 10:23 AM
if you can ride a road bike hard enough to fade a hydraulic brake system you are certainly "The Man"

keep the rubber side down
longslowdistance

Posts:680

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12/09/2013 10:53 AM
Unfortunately, in my case there is too much man, so the brakes need to be good. Remember the trp hy/rd is not a full hydro, just a reservoir at the calipers actuated by a cable. I am using ice tech rotors which should help with the heat dissipation.
Master50

Posts:233

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01/01/2014 08:01 PM
Sven Nys just won a world cup on his new disc equipped Trek. That is like 3 or 4 big races now
79pmooney

Posts:1129

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01/06/2014 03:36 PM
I just noticed that Katie Compton was racing cantis at Koksijde. (http://velonews.competitor.com/2014/01/news/the-world-cup-secure-katie-compton-switches-focus_312446). I had assumed she was riding discs being with Trek. Now, that photo does look like it is dry. But she was also riding cantis yesterday in Rome's mud. (http://www.cyclingnews.com/races/uci-cyclo-cross-world-cup-6-2014-cdm/elite-women/photos/287159)

Ben
Orange Crush

Posts:1191

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01/06/2014 04:02 PM
The deal with Trek for Nys (and I assume for Compton as well) is that now he can chose between either disc or canti, picking best option for each race. I assume mud means rapid disc wear = cantis better.

With Colnago Nys only had one disc equiped bike so the race he won on the new Trek was his first FULL race with discs.
Red Tornado

Posts:35

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01/07/2014 02:59 PM
A friend of mine has a BB7 equipped All City CX bike and he loves it. He also runs BB7 on his 29er MTB and has that setup dialed as well. I'm in the early stages of a CX build for next season, but with a used canti/V-brake frame and used wheels. Money is tight right now, so I guess you take what you can get - especially if it's steeply discounted stuff from fellow riders. If it pans out well for a season or two, I'll probably build a proper CX bike - most likely by then with discs. My friend tells me CX discs are "it" and he has switched from V-brakes.
I'm a little hesitant regarding discs though, because an MTB I had a few years ago with BB7's where the rear ONLY howled (as Old Fart put in) like a banshee. Swapped the rotor, caliper, pads (all one at a time); checked & double-checked setup; had my friend try to dial it; took it to the shop. Nothing would quiet that sucker down. Front disc ran dead quiet. Head shop guy thought it was some kind of vibration/harmonic thing maybe with the frame or rear wheel. We never thought of/tried tape behind the pads. Got to be extremely frustrating as it seemed you could hear that thing a mile away. Traded the MTB for a nice Fulcrum wheelset for the road bike and now am riding my old MTB (re-claimed from my son - he hadn't used it for a few years) with Shimano mechanical discs and they work fine.
If I go the disc route again, it will definetly be hydraulic. Like the auto adjustment and better pad clearance.
79pmooney

Posts:1129

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01/07/2014 05:39 PM
RT, your old MTB would make a perfect Boston commuter. Quiet with the old reliable front brake stop. But when you need attention, the howl is there on demand. There were times when I had almost that with the old Mafacs, famous for their squeal. When they were dialed in right, I could stop fairly hard reasonably quietly. But should a car cut me off, I would hit that front hard! Every head within a block or two with any hearing at all would turn. I would point to the offending car. Eyes followed my point. At about the same time, the driver, having been awakened from his stupor, looks up. Guess what? Everyone is looking at him! Driver slinks off with his tail between his legs. That was always fun!

Ben
Red Tornado

Posts:35

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01/08/2014 01:56 PM
LOL.  I hear ya on the commuting thing.  As a rider that commutes to work 2-3 times a week, having a loud "horn" would definetly come in handy at times.
Wish we would've thought of the tape thing; other than the brake howl that was one sweet mountain bike......
Cosmic Kid

Posts:1113

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02/03/2014 12:27 PM
Whaddya know....Vos rode discs to her win.

Nope, discs are never gonna catch on at the highest levels of the sport.
Just say "NO!" to WCP!!!!
Orange Crush

Posts:1191

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02/03/2014 12:37 PM
Nys and Stybar rode cantis though. "Nys had stated before coming to Trek that the added weight of his disc bike was still too much, but now the difference is under 600g, and will decrease in time, it will be interesting to see what happens throughout the next season."

For Vos a bit of extra weight just makes the training laps a bit harder.

http://www.cyclingnews.com/features/pro-bike-sven-nyss-trek-boones
Oldfart

Posts:480

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02/03/2014 02:51 PM
I think silver and bronze winning women were also on disc brakes.
Master50

Posts:233

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02/03/2014 10:31 PM
Van De Haar won the World cup using disks.
jacques_anquetil

Posts:218

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02/04/2014 08:09 AM
read somewhere that Nys would use the disks on a course that featured a sharp downhill where the extra braking power would be an obvious benefit.
THE SKINNY

Posts:402

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02/04/2014 08:38 AM
next year all the cool kids will be running disk on the front and cantis on the rear.
How we spend our days is, of course, how we spend our lives.
Ride On

Posts:435

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02/04/2014 04:55 PM
I will never understand the desire to stop the wheels from spinning relative to the frame.

I think what you want is to stop the wheels from sliding relative to the ground.

One does not equal the other.
Sweet Milk

Posts:93

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02/06/2014 09:31 AM
Perhaps, but unless you use a different braking mode slowing your wheels' spin is how you achieve slowing your speed, hopefully without your wheels sliding. Therefore the more control you have over how you slow the wheels' spin relative to the frame, the more likely it is that you will achieve slowing without sliding.

Off course what you really want is to arrest your forward motion in a controlled manner, how it is achieved is immaterial as long as it is legal...
longslowdistance

Posts:680

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02/06/2014 11:37 AM
Ride On, you've just made one of the best arguments for discs there is.
Oldfart

Posts:480

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02/07/2014 04:17 PM
Velonews has an article on the new Focus disc cross bike. They suggest that a through axle eliminates disc rubbing as well as making the fork - hub interface stiffer. It never occurred to me that disc rubbing the caliper was caused by that. I do know that I don't have that problem on my mountain bikes one of which is a 15mm through axle and the other 20 mm.

One of the reasons I ordered the Giant TCX with discs was because it has a 15mm fork through axle. Of course the bike is here and has been since Christmas, but it has no brakes (SRAM) so the bike won't be delivered to the shop until...summer?
sarpin

Posts:2

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02/12/2014 06:37 PM
My TCX0 arrived mid-October and I've had no issues so far.   After a short break-in period the only time I have had any disc/caliper noise at all is when the road is drying out and very gritty due to road gravelling.  Other than that I never have any pinging.  The through axle does it's job.  Great frame, nice offroad with the 35mms but I am sticking to 28mms as I am in road-only mode due to the brake recall. 

[URL=http://s22.photobucket.com/user/sarpin/media/DSC00459_zpsd8a717be.jpg.html][/URL]

This whole SRAM recall circus is getting very old.  DNR (Do Not Ride) on Dec 22nd, update on Jan 15th detailing temporary replacements.  We are now at Feb 12th and Norco / CyclesLambert both do not have any information on when replacements will be available in Canada.  Glad I chose to keep rolling as I retired my old winter bike.  Probably 1500km on it since Dec 20th.  Mostly sticking to a 40km rural loop with essentially no full stops.
Gonzo Cyclist

Posts:202

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02/23/2014 04:23 PM
BB7's are aweful Red Tornado, the absolute worst, if you want a Mechanical DIsc, go with the Shimano CX77's, they feel like Hydraulic brakes, but without the hassle of cutting lines, fugly brake hoods, etc......
I have a pair on one of my MTB's, these things work, almost as good as my Magura's on the Ritchey P-29'er
that bike looks pretty sweet Sarpin, it just needs some manly cross tires!!!


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