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View Full Version : Crossbikes- Let's talk brakes



GuyContinental
06-22-2012, 10:00 AM
I had a fantabulous commute this morning on a CX bike- Hit the WO&D from Arlington to the Difficult Run trail near Hunter Mill and then rode up around and through Lake Fairfax Park before rejoining the WO&D at Michael Faraday. Some OK MTB trails in there that were made pretty dang exciting by the utter lack of braking power on the bike... apparently braking is more of a suggestion than a requirement in CX.

So, I had such a great time (arrived at work an hour late muddy, bloody and grinning ear-to-ear) that I bought the bike (a well used Lemond Poprad) from the owner for a MTB detour/foul weather commuter. Now I need to upgrade the brakes, 'cause I ain't digging this not gonna stop thing. Frame does not have disc bosses so I suppose that there is some sort of v-brake setup that will work.

Ignoring weight & mud clearance and keeping in mind the lack of disc bosses what is the best way of amping up CX braking? I'm willing to spend some cash for performance.

jabberwocky
06-22-2012, 10:08 AM
My CX bike has discs (also a Lemond Poprad, coincidentally).

Cantis are what most CX bikes use, and unfortunately tend to not be that good. They are finicky to setup, so you could just have a setup issue. Depending on whats on there, upgrading to a decent canti like Avids shorty might help. Or you could try a better pad like koolstop salmons.

V-brakes fit the brake bosses but use a different cable pull than cantis (which use the same pull as road brakes). If you're singlespeeding, a few mfgs make brake lever hoods with MTB pull you could try, but I'm not familiar with any traditional brifters that do so. I do think problem solvers makes an adapter that converts cable pull; I have no idea how well it works.

Last upgrade option would be to upgrade the fork to something with disc bosses and run a mullet (disc front canti rear).

TwoWheelsDC
06-22-2012, 10:10 AM
I had a fantabulous commute this morning on a CX bike- Hit the WO&D from Arlington to the Difficult Run trail near Hunter Mill and then rode up around and through Lake Fairfax Park before rejoining the WO&D at Michael Faraday. Some OK MTB trails in there that were made pretty dang exciting by the utter lack of braking power on the bike... apparently braking is more of a suggestion than a requirement in CX.

So, I had such a great time (arrived at work an hour late muddy, bloody and grinning ear-to-ear) that I bought the bike (a well used Lemond Poprad) from the owner for a MTB detour/foul weather commuter. Now I need to upgrade the brakes, 'cause I ain't digging this not gonna stop thing. Frame does not have disc bosses so I suppose that there is some sort of v-brake setup that will work.

Ignoring weight & mud clearance and keeping in mind the lack of disc bosses what is the best way of amping up CX braking? I'm willing to spend some cash for performance.

Brake earlier :D

Seriously though, I don't know if there is a good solution. I also commute on a CX bike and have one particularly large descent on the way home. If it's raining, I just have to keep my speed down and pretty much ride the brakes the entire time, which just wears the brakes down faster. I also go through brake pads like it's my job. Right now, I'm using what I believe are the newest Shimano version of the Kool Stop salmon pads. They worked pretty well when they were new, but after a couple hundred miles, it's time to replace them again. This time, I might go for actual Kool Stops and see how those stack up. I think for me, it's not so much the braking power, it's the mushiness that cantis have when using brifters. On the days I use my road bike with dual pivots, I inevitably yank the brakes expecting some give, but the bite is immediate and I about fly off my bike...definitely highlights the crapiness of cantis for me every time I switch bikes!

GuyContinental
06-22-2012, 10:16 AM
Brake earlier :D

Eventually I just stopped bothering- it was like ohmygod! it's a log! I can't stop!!!! I'm gonna dieeeee... and somehow that was fun.

jopamora
06-22-2012, 10:22 AM
Congrats on the new to you bike. The Poprad is a nice ride and it has a fun name. New brake pads will help, but probably not the stopping power you want.

GuyContinental
06-22-2012, 10:39 AM
My CX bike has discs (also a Lemond Poprad, coincidentally).

Cantis are what most CX bikes use, and unfortunately tend to not be that good. They are finicky to setup, so you could just have a setup issue. Depending on whats on there, upgrading to a decent canti like Avids shorty might help. Or you could try a better pad like koolstop salmons.

It has Shorty 4's on it but the pads have seen better days- I might even borrow a car shortly to go on a pad quest. I did the mullet thing on a MTB SS for awhile, nearly lost an ear during a faceplant. Still, if I dialed the disc out enough it might be worth a go- the longer wheelbase of the CX might balance out the end-potential.

elcee
06-22-2012, 11:03 AM
...

So, I had such a great time (arrived at work an hour late muddy, bloody and grinning ear-to-ear) that I bought the bike (a well used Lemond Poprad) from the owner for a MTB detour/foul weather commuter. Now I need to upgrade the brakes, 'cause I ain't digging this not gonna stop thing. Frame does not have disc bosses so I suppose that there is some sort of v-brake setup that will work.

Ignoring weight & mud clearance and keeping in mind the lack of disc bosses what is the best way of amping up CX braking? I'm willing to spend some cash for performance.

I have a couple of bikes with cantis - one with Avid Shortys on it. In both cases, the best upgrade was to install Koolstop Salmons, and both bikes stop as well as the sidepulls on my road bike.

In general, though, cantis require a lot of fiddling to get right. You'll have to play with pad toe-in, straddle cable length, different hangers, etc. to find the magic combination of stopping power and quiet operation.

I haven't tried any of these, but there are V-brakes that are compatible with road levers:

http://paulcomp.com/minimoto.html

http://www.trpbrakes.com/category.php?productid=1040&catid=185

http://www.trpbrakes.com/category.php?productid=1120&catid=185

(Remember that brake levers have slightly different pull ratios, so certain combinations of V-brakes and levers won't work as well as others.)

P.S. If you haven't read this yet, here's all that you need to know about cantis:
http://www.sheldonbrown.com/canti-trad.html

DaveK
06-22-2012, 11:48 AM
Both of my cross bikes couldn't stop for... crap. No matter the pads, etc. I'm going to change the current one to mini-v brakes as soon as I get around to it. I'm assembling the parts to change it to SRAM anyway so while it's under the knife I'll do the brakes as well.

What to do about stopping? Plan ahead...

GuyContinental
06-22-2012, 01:18 PM
The Interwebs give a lot of cred to the little cheap Tektro 926 linear pull v-brakes plus kool stop pads-

Brakes- http://www.amazon.com/gp/product/B002F91TP4/ref=ox_sc_act_title_4?ie=UTF8&m=A2TE9IQP68MWQU

Pads- http://www.amazon.com/gp/product/B001CJZ0Q2/ref=ox_sc_act_title_1?ie=UTF8&m=ATVPDKIKX0DER

With adjustable 90 deg noodles and some new cables I'd be under $80 for the attempt. The Paul's are super sexy but wow, they aren't cheap ($130/per... I did say that I was willing to spend money though ;-).

How does the mullet CX work out? Is it tough to balance braking power fore and aft? I really want stopping power irrespective of weather...

DaveK
06-22-2012, 02:53 PM
How does the mullet CX work out? Is it tough to balance braking power fore and aft? I really want stopping power irrespective of weather...

I'd do that if it weren't for the expense of a new fork. Balance between brakes really isn't an issue since you shouldn't be using your rear brake much anyway. 90% of stopping power should come from the front, and I've always found mechanical discs easier to modulate that hydraulics.

vvill
06-22-2012, 04:26 PM
Not a CX bike, but I have Tektro mini v brakes hooked up to Shimano brifters on my folder (actually just one brifter - the right side, Tiagra). I haven't been particularly happy with the performance esp in the wet though that might be just that they're not well adjusted.

My next bike may well be a CX/commuter mostly because I would like something with disc brakes for going downhill in the wet - I'm only going to look at ones with disc mounts. My MTB had disc brakes back in the early 2000s - it's sort of strange that road/cross bikes have taken so long to catch up.

DaveK
06-22-2012, 04:37 PM
Not a CX bike, but I have Tektro mini v brakes hooked up to Shimano brifters on my folder (actually just one brifter - the right side, Tiagra). I haven't been particularly happy with the performance esp in the wet though that might be just that they're not well adjusted.

My next bike may well be a CX/commuter mostly because I would like something with disc brakes for going downhill in the wet - I'm only going to look at ones with disc mounts. My MTB had disc brakes back in the early 2000s - it's sort of strange that road/cross bikes have taken so long to catch up.

Blame the UCI. And all us Freds who want the bikes just like the pros ride.

Dirt
06-22-2012, 09:42 PM
The cantis on my cross bike work flawlessly and have from day 1. Disc brakes work better on pavement, but are too much for dirt road rides (which is what I use the cross bike for). The huge braking power combined with the small contact patch of cross tires make it way too easy to lock up on dirt roads at high speed. I know most people don't use their cross bike in that way, but they work perfectly for the riding I do.

Greenbelt
06-22-2012, 09:51 PM
I'm a big fan of disk brakes for commuting -- glad to see them on cross bikes now, since cross bikes can be very good for certain types of commutes (like mine!).

jopamora
06-22-2012, 10:13 PM
Dude, did you buy this bike (http://washingtondc.craigslist.org/doc/bik/3095318881.html)?

bluerider
06-22-2012, 10:16 PM
I took off Avid Shorty 6s and installed Avid Ultimates on my Blue Norcross EX. Love them. Mega power, easy modulation, and great adjustability. They were a huge upgrade over the original brakes. They can also be setup wide for mud clearance or narrow for power. TRP and Paul make nice cantis for cross bikes as well. But for the price Avid Ultimates can't be beat in my opinion.

http://www.cxmagazine.com/wp-content/gallery/sea-otter-day-1-batch-1/sea-otter-2010-6848-cxmagazine_1.jpg

GuyContinental
06-23-2012, 02:16 PM
Dude, did you buy this bike (http://washingtondc.craigslist.org/doc/bik/3095318881.html)?

Nope- a black 57 with a known history.

GuyContinental
06-25-2012, 12:32 PM
Thanks for all of the thoughts!

As V1.1 I replaced the utterly dead v-brake inserts on the rear Shorty's with Kool Stop Salmons, reduced the wheel clearance a bit/tuned the brakes and ordered the Paul MiniMoto (Paul stuff always tickles my bike-bling nerve which put them over the line vs the Avid Ultimates). If that doesn't work over a few hundred miles, I'll probably go with a mullet using an Avid BB5 mechanical, a new fork, rebuilt wheel and then put the Paul on the rear.

I meant to take it out this morning for my new-found mid-commute LFP romp but woke up with some toddler-vector inspired cough... sigh

FWIW I can't figure out the physics behind Dirt's note on the small tire surface area and disc brakes (but if anyone would know I assume that he would)- assuming two equally grabby brakes (set for power not modulation) braking from the hub (i.e. disc) is going to add modulation through the spokes and tire lugs whereas braking from the rim essentially limits that system modulation to the tire... thus, you should have more skidding from a rim brake than a disc. I've ridden narrow tires (2.1, so only 18mm wider than my CX tires) on my various disc-equipped mountain bikes from time to time at pretty high speed (albeit probably not as fast as Dirt...) and have never noticed a particular propensity to skid provided that I wasn't locking up the brakes.

OneEighth
06-25-2012, 01:22 PM
+1 for most things Paul.
Why not go with the Neo-Retro? I would expect they would honk a lot better.
Also BBB pads are lovely.

jabberwocky
06-25-2012, 03:08 PM
If that doesn't work over a few hundred miles, I'll probably go with a mullet using an Avid BB5 mechanical, a new fork, rebuilt wheel and then put the Paul on the rear.If you do end up going this route, spring for BB7s. They are different brakes, and the BB7s are not much more expensive and much better.


FWIW I can't figure out the physics behind Dirt's note on the small tire surface area and disc brakes (but if anyone would know I assume that he would)- assuming two equally grabby brakes (set for power not modulation) braking from the hub (i.e. disc) is going to add modulation through the spokes and tire lugs whereas braking from the rim essentially limits that system modulation to the tire... thus, you should have more skidding from a rim brake than a disc. I've ridden narrow tires (2.1, so only 18mm wider than my CX tires) on my various disc-equipped mountain bikes from time to time at pretty high speed (albeit probably not as fast as Dirt...) and have never noticed a particular propensity to skid provided that I wasn't locking up the brakes.I have a CX bike with discs and have never had any issues overwhelming the tires. Honestly, I don't think road mech discs are that much more powerful than good rim brakes, they are just more consistent (and in the case of cantis, less bitchy to adjust).

TwoWheelsDC
06-25-2012, 03:21 PM
I took off Avid Shorty 6s and installed Avid Ultimates on my Blue Norcross EX. Love them. Mega power, easy modulation, and great adjustability. They were a huge upgrade over the original brakes. They can also be setup wide for mud clearance or narrow for power. TRP and Paul make nice cantis for cross bikes as well. But for the price Avid Ultimates can't be beat in my opinion.

http://www.cxmagazine.com/wp-content/gallery/sea-otter-day-1-batch-1/sea-otter-2010-6848-cxmagazine_1.jpg

Oh man, those look sweet. I'm definitely going to look at those as the next upgrade to my commuter. I like the skinny-ish tires too. Mine has 32 semi-knobbies on it now and I'm considering going to more sporty 28s.

GuyContinental
07-09-2012, 08:09 AM
Quick follow-up on this project- quite simply the front Paul brakes plus Kool Stop pads rule. The bike stops NOW with no stutter.

I took the bike on some technical trails in Rhode Island last week (think yellow loop at Gambril) and had no problem stopping (to portage...) before pitching off the 6'-10' chutes. Taking the CX on real MTB trails was a heck of a lot of fun- it was absolutely not the right bike for the trail (7" of travel and a FS would have been nice) but I had loads of fun in really unexpected ways- the CX required a LOT of riding strategy in both technical climbs and descents. I look forward to taking it out locally- it should be a nice equalizer when riding with my wife (I'll be either walking or bleeding on the ground).
1336- noop, I walked this one, probably would have on any bike. Easily a 10' drop

1337- I at least tried this- it laughed at me and spit me out.

GuyContinental
08-13-2012, 10:31 AM
Second follow up for those pursuing CX brake knowledge... for those of you that actually know what you are doing on a cross bike, you will laugh at this but I come from 18+ years mountain biking so much of this did not immediately come to mind. After 600 miles (maybe 200 on dirt- some of it very technical) these are some of my observations...

You have (essentially) three possible braking positions on a cross bike:

Hoods- lowest brake power, good for climbing, nearly impossible to both hold on and brake, also tough to get the ft wheel off the ground- you can wrap your fingers and scrub some speed with your index fingers but stopping isn't really going to happen. Alternatively, you can hold on by pinching thumb and index fingers leaving four fingers for the brake- this will stop you but good luck holding on unless you have monster hand strength

Drops- good brake power, very fast, rough to transition out of and hard as heck on the body. I call this the Danger Squirrel posture because your head is basically over the front wheel and with an aggressive set up you are verrry low and verrry forward. For awhile I was riding this way exclusively when heading downhill- it was great- I could brake (and stop), I could hold on, I could even climb. However, roots and technical sections really hurt and I was always theees close to pitching over the bars. Also, steep downhill gravel is really bad news when your weight is all the way forward...

Bar Tops with interrupter levers- great braking power, MTB handling, better front wheel lift but not so great climbing and not extremely fast. Superior for getting over logs or through major technical sections.

I added the interrupters over the w/e and I am now a happy camper- Hoods for climbing/cruising; Drops for Danger Squirrel fast; Bar tops for most descending and technical riding. I still have a long way to go on the learning curve (I bleed a lot) but I have a ton more confidence in braking now that I have decent equipment and some real tools in my technique.

TwoWheelsDC
08-13-2012, 10:59 AM
Bar Tops with interrupter levers- great braking power, MTB handling, better front wheel lift but not so great climbing and not extremely fast. Superior for getting over logs or through major technical sections.

I added the interrupters over the w/e and I am now a happy camper- Hoods for climbing/cruising; Drops for Danger Squirrel fast; Bar tops for most descending and technical riding. I still have a long way to go on the learning curve (I bleed a lot) but I have a ton more confidence in braking now that I have decent equipment and some real tools in my technique.

I really like having these on my CX bike, even if I don't use it for actual CX...but for commuting in traffic, or cutting from MUPs/sidewalks to grass or gravel, I really like the stability of having my hands on the top bar with brake levers right there. It's like having the urban handling benefits of a flat-bar, but with the added hand positions of drop bars. Oddly, I don't miss them at all when I'm on my road bike, but that thing stops sooooo much better than my CX bike, so I can stop just as fast, if not faster, on the hoods of my road bike than I can with the cross-levers on my commuter. But I have seen a few new steel road bikes with top levers, but I don't think we'll be seeing them trend on AL and Crabon bikes any time soon.

GB
04-28-2015, 06:55 PM
Question about interchangeable wheeles from my MTB to my hypothetical CX bike.

I have a MTB with disc brakes. I'm looking at a XC frame. What needs to be the same in order to swap my wheels out? I'm guessing disc size needs to be the same. I'm guessing that impacts caliper location. Does that impact disc brake mounts/frame?

If I have the best setup, what will I need to adjust when switching wheels?

If you were going to pick 1 disc size to go between MTB and CX what would it be?

Thanks

Phatboing
04-29-2015, 09:21 AM
Question about interchangeable wheeles from my MTB to my hypothetical CX bike.

I have a MTB with disc brakes. I'm looking at a XC frame. What needs to be the same in order to swap my wheels out? I'm guessing disc size needs to be the same. I'm guessing that impacts caliper location. Does that impact disc brake mounts/frame?

If I have the best setup, what will I need to adjust when switching wheels?

If you were going to pick 1 disc size to go between MTB and CX what would it be?

Thanks

1. The disc size depends on the frame/fork design - my Colossal can take a 160mm disc on the fork, but only 140mm rear on ze frame.
2. Someone else will have to answer that - I have no idea. My guess is you shouldn't have to adjust stuff if you've set up both bikes right.
3. 160mm. Stop good.

jabberwocky
04-29-2015, 09:26 AM
You may have to adjust the caliper each time you swap wheels. Disc hubs and rotors are all slightly different. Whereas wheel one is perfectly aligned, wheel two might rub (which is why the calipers have the ability to shift around a bit).

hozn
04-29-2015, 11:51 AM
You can get little shim washers to get the rotors to be as identically spaced as possible. AFAIK @vvill has done this. In a perfect world you build with the same hubs, but even that is not guaranteed to mean consistent rotor spacing. Rotors warp, so you have to be willing to periodically re-true them (not that hard with a crescent wrench or the Park Tool). Also even same hubs might be a fraction of a mm different, though typically you can find a middleground pad position that works. On my previous wheelset, I knew when swapping wheels that I would have to adjust -- e.g. one click on the inboard pad and 3 clicks on the outboard (Avid BB7), so it only took a few seconds to do that. My wheels now (built with same hubs) can be interchanged without any adjustment -- which is good, since my Spyre brakes don't have indexed pad adjustment. It is only the front fork (with the larger rotor) that I have ever had to adjust.

I am curious about the re-centering of hydro brakes; if the rotors fit within the caliper will the auto-centering take care of small (e.g. 1mm) differences in rotor position? (@jabberwocky?)

As for size, I would choose 160/160 by default, though I am running 160/140 on my CX and road bikes and it works just fine. As hinted above, I suspect that the bigger the rotor, the more likely you're going to have to adjust your calipers when swapping wheels. I definitely wouldn't go larger than 160.

jabberwocky
04-29-2015, 12:30 PM
I am curious about the re-centering of hydro brakes; if the rotors fit within the caliper will the auto-centering take care of small (e.g. 1mm) differences in rotor position? (@jabberwocky?)

I'm honestly not sure about that; I have lots of bikes and lots of hydraulic brakes, but zero experience swapping wheels between them. For alignment I tend to just loosen the caliper bolts slightly, squeeze the lever, retighten the bolts (with the lever held) and that works to center it pretty well.

I will say that different brands/models run at different distances from the rotor. My older Avids seem to be pretty generous. My formulas run the pads much closer to the rotor and would probably be much more sensitive to tiny changes between wheels.

vvill
04-29-2015, 08:31 PM
You can get little shim washers to get the rotors to be as identically spaced as possible. AFAIK @vvill has done this.

Yeah I have. It was a pain to set it up, and I still need to do some adjustments when I switch wheels. If rotors were all identical and stayed identical I guess this method could work. Also, this only works for 6 bolt/ISO not Shimano Centerlock hubs.

FWIW I have the Syntace shims not the the Wheels Mfg ones (which come as 20 separate 0.2 shims - one per rotor bolt! So you can get 0.6mm max from one pack with 2 left over. Really stupid for $15 MSRP.) The Syntace are one piece bags of 8 (so up to 1.2mm in a bag) which is much more convenient considering I have 4+ shims on some of my wheels.


I would also choose 160/160 but have 160/140 due to how my bike was built. I think most CX/road frames will handle both those sizes.