Disc brakes cyclocross bike observation.

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  1. JS

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    So...epic wet rainy conditions in SoCal today for the elite men. Worked the pit for a few friends. There were six guys racing disc bikes and five had to ditch the disc bike for their canti "B" bike when the pads wore enough to render them useless without adjustment. The one disc bike that didn't have an issue, Ryan Trebon on his SRAM red hydraulic disc bike. So unless you are running hydraulic brakes discs are actually worse in crappy conditions than canti's. So two seasons ago the UCI gave the go ahead for discs in elite competition and many on this forum were sure everyone would be on them within the year, well nope. Still not ready for prime time.

    For all the good they've done me, I might as well have stuck them up my arse. - Mark Renton
    Posted 4 months ago

  2. Cosmic Kid

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    and many on this forum were sure everyone would be on them within the year

    . I don't recall anyone saying that.

    Just say "NO!!" to WCP!

    "Want to get faster? Work harder, eat better, cut the crap. Instead of talking the talk, work the work"
    Posted 4 months ago

  3. gabbard

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    Can someone explain the mechanics behind this? MTB races are run in the mud and rain, MTB riders in rainy places don't replace their pads every day, so why are cross bikes going through pads so quickly? I am not doubting that it happened since you have first hand experience, but what is different about the brakes that is causing this?

    Mechanical disc brakes have lever adjustment - couldn't they have just rotated the threaded adjustment barrels on the levers?

    Confused in CO...

    Posted 4 months ago

  4. longslowdistance

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    I wasn't there but mechanical vs hydro probably wasn't the difference, but rather pad material.

    Posted 4 months ago

  5. JS

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    lsd, it wasn't that the pads were worn completely out it's that they wore enough to render them useless as the lever hits the bar before they engage. This is strictly a function of mechanical discs, hydraulics self compensate by putting more fluid in the system. Gabbard, mtb races are rarely raced in conditions like today, I have never raced my bike MTB in stuff like this in 20 years of racing. And mechanical discs have manual pad adjusters at the caliper which works but makes it tough during a race, adjusting the cable pull messes with the mechanical advantage making them feel even worse.

    Posted 4 months ago

  6. stormchaser

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    This has to be a mental on the rider. I ride more miles in a couple of weeks on my 29er riding the DEMO forest in Santa Cruz in shitty condition then most CX racers will have in a season. I have had zero problems and still on the original pads, are we to believe that racing around a playground in Socal demands more from a disc brake then a good day of MTB. CX is for roadies, roadies are soft!

    Posted 4 months ago

  7. JS

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    Stormchaser, you have either got to be joking or completely clueless. If the latter lets use an example to prove it, Aaron Bradford of the Rock Lobster cyclocross team also happens to be a ripping Gravity MTB racer (along with teamate Scott Chapin) Bradford recently won the Pro Super Enduro gravity event in Demo Forest earlier this year. Me,I race expert XC and Super D and dabble in Downhill racing on a whim at times, in fact I won the Sea Otter DH in the sport class two years ago on my trail bike as a last minute entry. I frequently get up your way every year, I'll bring my Santa Cruz Blur LTc and we'll hook up for a ride in Demo Forest and you can show me how soft I am.

    some pictures of Arron Bradford being "soft"
    http://www.aaronbradford.com/#portfolio

    Posted 4 months ago

  8. Jah

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    agree with others, something is up with pad material. you'll see ton of disc, just give it some time for the morons that bought it this year to fund the development

    bring that over suspended, midget-wheeled 26er to Michaux, I won't have to show you how soft you are - the rocks will do it for me. Call your dentist first, it's dark, cold and icy these days. Sea Otter DH in the Sport Class? ok then, a bear will probably eat you

    Posted 4 months ago

  9. dj1979

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    Maybe they were all using avid brakes...5 out of 6 pair going bad sounds about right.

    Posted 4 months ago

  10. JS

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    Jah or is it pa biker, you East coast MTB guys and your inferiority complex are hilarious. Anything that can been ridden on a rigid bike with wagon wheels at 3mph isn't really something to brag about. Come out west where we actually ride fast and there is not the option of just putting your foot down to keep from falling over.

    Posted 4 months ago

  11. CB2

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    mtb races are rarely raced in conditions like today

    Welcome to New England

    Jam Econo
    Posted 4 months ago

  12. dkri

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    Hydros self correct for pad wear, it's as simple as that. The only way to adjust for pad wear on mechanicals (at least on BB7s, which are predominant and the only ones I've used) is the little red knobs at the calipers. With the hydros on my mtb, I never had to adjust the pads and replaced them about 1.5 seasons into their use. With mech discs, pad adjustment is a constant.

    Tim Johnson, undoubtedly the earliest elite racer advocate of discs, has said that he's regularly had to pit for pad wear adjustment when using mechanical discs.

    Here is a picture from a race where my rear brake (disc) just plain stopped doing anything except making noise about 2 laps in, but where my front brake (canti) worked fine the whole time.

    Given my two cx bikes, I have a pretty good basis for comparing them.

    PS - Stormchaser, I'm a Cat 1 in mtb, Cat 2 in cx, and Cat 3 in road.

    For disclosure purposes, I am a partner in November Bicycles. This fact probably colors everything I say. I'm clearly not to be trusted.
    Posted 4 months ago

  13. longslowdistance

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    JS, good point about the rapid wear, mechanicals, and road brake lever travel. It's still a wear issue, though, and perhaps the pad compound is the real culprit.
    I've raced 6 hr mtb enduros in cyclocross level mud and enjoyed many long rides in Pisgah's sloppy granite slurry but experienced minimal pad wear with Avid mechanicals. Would that minimal wear been enough to change function with road levers? Doubt it (I'm experienced with road Avids too).

    dkri, there is another adjustment option for road: a barrel adjuster at the lever. Wouldn't be useful during a cross race, but OK for casual riding.
    It's still the pad material. Use more durable material with less brake power (but still enough for cross I would think) and the perhaps the problem will be managed?
    PS I don't want to tell crossers what to like, I just want good discs for my adventure bike.

    Posted 4 months ago

  14. dkri

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    I've used both metal and organic pads. Not much difference. In-line barrel adjusters aren't recommended for brakes, and in any case if it's not useful during a cross race it's useless for cross.

    "PS I don't want to tell crossers what to like, I just want good discs for my adventure bike." Which is great, so long as I don't have to be your guinea pig.

    Posted 4 months ago

  15. Jah

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    only girly men and self proclaimed Sport Class podium winners dab their feet

    who wants to go to California, anyways? Its just going to fall into the sea one day

    Posted 4 months ago

  16. Keith RIchards

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    Some quality chest beating going on here. Great stuff...continue. Don't mind me....

    It is his word versus ours. We like our word. We like where we stand and we like our credibility."--Lance Armstrong.
    Posted 4 months ago

  17. Orange Crush

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    Not surprised about the observation, it mimics my own experience winter commuting. There is very little time between the day you start noticing the wear and do a barrel adjustment and the moment that brakes become totally unusable/dangerous (mechanical brakes). Several brake pad replacements each winter. I don't think there's much that can be done in terms of pad material, it's just a known fact that mud/clay wear things like crazy. By comparison, on my winter road bike which sees similar conditions and usage I'll only go through one pair of regular brake pads. You don't get the superior brake performance initially but at least they keep working.

    The wise man said follow me...and he walked behind.
    Posted 4 months ago

  18. Keith RIchards

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    And seeing as the idea is to use your brakes as little as possible...

    Posted 4 months ago

  19. Gonzo Cyclist

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    "Maybe they were all using avid brakes...5 out of 6 pair going bad sounds about right."
    the new Shimano cross disc's are pretty sweet, just did a pair for my boss's drop bar MTB, as far as wear? The jury is still out on that one, so we'll see how they wear, but I swear the modulation is as good as any hydro brakes out there
    I could see where some serious grit would grind the hell out of the pads, but who knows how long they have been riding the same set. I would rather wear out some pads and discs instead of a set of expensive rims
    Thanks for the update JS

    Photobucket
    Posted 4 months ago

  20. watermoccasin

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    I'll take some of the chest thumping action
    ;-)

    (not me on the ground, but my bike in the other photos)

    Photobucket

    Photobucket

    Photobucket

    Posted 4 months ago

  21. Mike

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    You cross guys are crazy

    Good to see a nice informative exchange of ideas on the forum. Keep it going

    Posted 4 months ago

  22. velojo

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    Interesting comments. When I did the SSCXWC inSeattle there were three guys with discs walking the steep downhills because their brakes "failed". I just guessed that they had worn out brakes prior to the start, but maybe there is something to that. The mud was bad, but it was a very thin/wet mud that was very gritty like polishing compound. I noticed my canties were a mix of red compound from the brake, silver from the rim, and black/grey from the dirt, but functioned very well.
    Don't know what brakes they were, but it is interesting to ponder.

    Posted 4 months ago

  23. longslowdistance

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    That's a compelling story, clearly a fail for discs.
    Why aren't mtbers suffering as much?

    Posted 4 months ago

  24. jacobus

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    Watermoc,
    Were those from State CX last year?

    Posted 4 months ago

  25. watermoccasin

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    Yup, Raytown
    I weighted my bike before and after I washed it... 7+ pounds!

    Posted 4 months ago

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