The bike industry is abuzz with news of a global recall of 19,000 sets of high-end SRAM hydraulic road brakes; and it turns out a cyclocross race in Bend, Oregon on December 7th had a lot to do with it.
SRAM made the voluntary recall announcement on December 13th, citing, “last weekend’s Cyclocross racing in the US, in sub freezing temperatures,” as the main culprit. That event was a two race weekend that started with the UCI-sanctioned Deschutes Brewery Cup, which was followed the final stop in the Oregon Bicycle Racing Association’s Cross Crusade series.
Two days after SRAM’s official announcement, we noticed this post on race director Brad Ross’s Facebook page:
I’ve promoted many races in my career. But this is the first one that resulted in a major product recall. Bucket list, check.
Curious, we contacted Ross to find out more.
Ross said he first realized something was wrong when a friend of his, Giant Bicycles sales rep Paul LaCava, rolled up to him after his race. “He came up to me and showed me his brakes and they were completely gone,” Ross said, “They weren’t just fading, you could press the levers all the way to the handlebars.”
Ross added that he and his crew designed a “treacherous course” that was very technically demanding, so brakes were getting a good workout. But it turns out that it wasn’t the course or the riders that caused the handful of brake failures. It was the cold.
Here’s more from Ross:
“I went and talked to some of the guys in the pro tents and said, ‘Hey guys, these brakes are failing’ and they said, ‘That’s OK, we’ve got multiple bikes’ [pro and elite riders switch bikes during races to always have a clean rig]. Well, it turned out by the end of the race all the brakes had failed, even the pit bikes — before the rider would even get to the pit.”
Ross said temps were hovering between zero and five degrees throughout the weekend. “It was pushing it for racing a bicycle. We were talking about pulling the plug on the event.”
The event went ahead and has become an instant classic for those who were there. Ross said there were a few trips to the hospital for frostbite, but other than that the main casualty of the tough conditions appears to have been SRAM’s new brakes.
— SRAM has set up a website to answer questions and deal with the recall.
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And Bike Snob pens another classic:
Upon reading this, retrogrouches around the world wove flowers into their beards and danced arm-in-arm around the lugged steel maypole, reveling in the irony that the very conditions in which hydrolic di*ck breaks are supposed to excel were instead their undoing.
“Rim brakes RULE!”
No! Coaster hub or drum brakes rule!! 😉
Their hydraulic caliper brakes are subject to the same recall for the same reasons, fwiw.
Yep, in this case it’s hydro vs. cable — not disk vs. rim.
I met a few people with cable-actuated disc brakes that were also not working in the cold. Moisture in those long stretches of cable housing froze up.
And how many people that had trouble with their canti’s? I can’t imagine that an extra 1-2 feet of housed cable would be a huge problem compared to canti’s.
This is why the bike industry sucks. Innovation just for the sake of innovating. Hydraulic brakes on a bike sound totally stupid when a simple cable has worked so well for so long. I guess there are big bonuses for the marketing wizard that can convince a bunch of spandex wearing dentists to swap out their ridiculously simple cable brakes with some new $500 state of the art hydraulic brakes. This and the radio controlled derailleurs are solutions in search of a problem.
I rarely see the spandex wearing dentist crowd taking shots at other varieties of cyclists. Hydraulic discs make plenty of sense in a cross race, which are fun in jorts or spandex; rim or disc; cable or fluid; tipsy or sober. They make even more sense on an mtb –successfully at that. So while not everyone needs disc, there’s a time and a place AND I am certainly glad the spandex wearing dentists can afford to test new technology, while we all keep the industry accountable. Everyone smile and high five. Bikes are fun.
generalize much?
Have you tried hydraulic rim brakes before? They’re pretty awesome. They’re very popular in Poland (where I live) and it’s pretty cold there so don’t throw the baby out with the bath water. Maguro is the dominant brand there for them.
Operative word is “sound.” In reality, they are the best thing to happen bikes in a long time, aside from the Hite-Rite and mustache handlebars.
i can’t imagine you’ve spent a ton of time on a mountain bike to see disk brakes’ benefits compared to rim brakes
To each their own. I just built up a Masi Evo with an ENVE Road Disc fork and TRP Hy/Rd hydraulics on the front. I do a significant amount of climbing/descending and my primary road training route accesses trails I often ride with my MTB, which I then descend with far more confidence on hydraulic discs, prompting me to replace my rim-brake road bike with this project. Well worth it to me! It runs 10-speed Ultegra Di2, by the way, which is WAY smoother and quieter (other than the FD servo) than my Ultegra and DA builds (and it auto-trims, a feature I like since I cross-chain a lot).
Incidentally when deciding on a hub for the front wheel build (Reynolds MV32C rims) I ran into your attitude regarding 6-bolt versus Shimano Centerlink. I opted for the latter based on all the positives and it ended up in a lighter, straighter, easier rotor build which brakes nicely. A year ago everyone was saying “why change this??” and now three other hub-makers and two other brake-makers have licensed it and are touting its benefits.
Correction: Center-lock. P.S. When you need your cavity filled come see me… 😉
I dunno. I work in a shop and I see what is being said here. I hear the mechanics complain about this stuff a lot. I’m with Jimmy on this.
You know, I kind of agree with Jimmy, except maybe ‘problems in search of a solution’ describes some stuff like 11 cog rear clusters. However let me say that for certain bikes I ride hydraulic disk brakes are absolutely the best and I would never switch to anything else. Specifically, cargo bikes in Portland where it rarely freezes. So let’s have some light instead of heat, how did the brakes fail? Guess the low temperatures had a lot to do with it. Mr. Feynmann still dead alas.
Meanwhile, with 100,000 + miles of hard use and lots of benign neglect on my original S-word hydraulic disk brakes, I’m gonna keep believing.
Here’s a bike build you’re not going to like:
http://road.cc/content/news/100550-trick-tech-martyn-ashtons-colnago-c59-disc-video
Apparently trials experts seem to like hydraulic discs, and my friend with a disfigured left hand who has trouble shifting her front derailleur is stoked to see that with this new technology she can keep up with us by just pressing buttons!
I heard it was something like O-ring seals, just like on the space shuttle…
We need to resurrect Richard Feynman to lead the investigation…
I pretty sure Jan of Vintage Bicycle Quarterly is going to say, “this is why the French Constructeurs used races and timed endurance events to test and improve technology before it got this far into production.”
my canti’s worked just fine. that said, discs work so much better. . . until they dont
Recall originally posted early November in CX Magazine.
http://www.cxmagazine.com/sram-road-hydraulic-brake-recall-red22-s-700-disc-rim-serial
That was a more limited recall, limited to certain serial numbers. This applies to all.
Personally, I prefer to old mechanical rim brakes. I’m always replacing pads on my hydraulic brakes and I don’t ride that hard.
I find it amazing that disc brake pads for my bike cost 2X more that they do for my car. And the pads on my car have a half dozen extra features to improve performance. Supply and demand, I guess.
Not supply and demand Brian, it’s the economy of scale. Makes much more sense when you look at it that way.
Because cars have 4 brakes and bike have 2? I assumed the number of bikes made was about the same as the number of cars made.
If you include the “BSO” thats true. High end disc equipped bikes though are pretty rare. I think all cars are now coming with front discs and about half of them rear.
I wonder if they need more precision making the smaller and thinner pads too.
the scale comes from the number of cars on the road vs number of bikes with disc brakes on the road, and the amount of use (and therefore wear) each gets. Still, some of those bike brake pads are pricier than they need to be IMHO
Anybody have any details about the nature of the failures? It is hard to draw conclusions without knowing what the weak link was. I tend to agree with the simpler is better approach but I recognize that technology does sometimes advance.
From what I’ve read the main gasket that holds the brake fluid in the lever failed due to the cold temps. I’m curious if that leaked break fluid on the bikes, or if there just wasn’t enough pressure to actuate the calipers.
I’m a big fan of hub-based brakes (both disc and drum) and I really hate rim brakes. But ironically except for rim brakes, I’ve never seen the reason to go hydraulic other than to shave off a few grams if you happen to be an elite racer.
Good ole Avid mechanical discs have tons of stopping power, are super easy to maintain and don’t cost much in pads. BB7s FTW!
Have you ridden a Shimano hydraulic disc brake yet? Man, oh man they are sweet.
It’s funny how much grief people gave Shimano for taking their time on their road disc systems, while SRAM rushed into this with some fictitious deadline based on demand that’s not there yet (read: Interbike, Eurobike shows).
To be fair, though, that weather system wreaked havoc in so many ways. Several of my friends and I had problems with our cars; my anti-lock and AWD systems failed temporarily, and my friend drops off his 4WD truck tomorrow that hasn’t worked right since. I got stranded in southern Oregon on icy roads that shut down I-5 (or should I say speeding truckers losing control did), and the anti-freeze in my windshield washers froze. Also I forgot and left carbonated beverages in the car overnight…
I haven’t tried the SRAM systems yet, but the Shimano system on my BMC MTB is indeed sweet, prompting me to build up a TRP Hy/Rd-based front end on my new road bike – and what a difference in descending!!
Braking on my drop bar bike is painful now that I am used to xt hydros on my flat bar bikes.
yeah I’m with ya on the BB7’s…noisy, but great stoppers. I guess I should try some organic pads?
Yeah, or your rotors are contaminated. Change your rotors AND your pads – same time – and bed in the new stuff. Your brakes will be quiet, with little exception.
Take your BB7s and add a tremendous amount of modulation, subtract time spent adjusting both cable tension & inboard pad position according to wear, reduce the amount of force required at the lever, keep replacement pad price in the same ballpark and you have some of the advantages of hydraulic discs. I know that BB7s work fine (everything works fine, as someone else here pointed out) and I’m not encouraging you to switch, but saving weight is at the bottom of the list of benefits if it’s even on that list at all.
Well, there is the issue of rim sidewall wear. I work in a bike shop and we see this a whole lot. Sometimes even people who should know better let their rims wear to the point where the tire blows them apart.
My Shimano hydraulic disc brakes worked just fine for the Sunday Bend race.
Yep. If we’ve learned anything about disc brakes, it’s that they just don’t work . . . Except on cars . . . And motorcycles. And every mountain bike being made today.
Calling disc brakes an “innovation” at this point is a lot like saying your CD player is next big thing. They’ve been standard equipment on mountainbikes for over a decade. We can safely expect them to be awesome on everything else very soon.
Look, if you just don’t want a new bike, don’t buy one. Rim brakes are fine. Got ’em on my bike. They’re fine in the same way that down-tube shifters were “fine”, solid tires were “fine”, halogen bulbs were “fine”, and hairnet helmets were “fine”. All that stuff worked. Fine.
If you live long enough, you’ll own a road bike with tubeless tires, electronic shifting, and hydraulic disc brakes. OR you can be that guy with the Peugot and the wool shorts who keeps talking about the superiority of Schwinn “back in the day”.
The story here is not that disc brakes are suddenly going to vanish, it’s that SRAM had a major oversight in the design process and now they’re paying for it.
Hydraulic disc brakes are happening for road and ‘cross with or without your approval, or Shimano wouldn’t bother. Five years. They’ll be totally standard equipment on road bikes within five years – along with tubeless tires and probably electronic shifting on anything over $2k.
Just don’t make me go to 11 speeds just yet!! 🙂
Nice post, Magic Hat.
I’m definitely closer to the guy with the Peugeot and the wool shorts end of the spectrum, but it’s not that I love Schwinn, but that sometimes simpler *is* better. Fewer moving parts, exotic proprietary subassemblies, obsolescence, OBD II and all that. I have no experience with any brake innovations since the late eighties cantilevers, so you tell me: are today’s brakes going to still be working in 25 years? Are there more wear parts on these than cables, housing, and pads? Durability, repairability, standardization, have their charms too.
Dude, If you’re still riding a brake from 25 years ago, it’s been rebuilt a few times. Any mechanic worth half his wage can rebuild a 10-year old hydro brake.
Hydraulic disc brakes are already standardized. They are repairable. Durability per dollar is well beyond that of canti’s, and yes, they do work better, and that doesn’t just mean they’re more powerful.
News flash: power isn’t everything. You can lock up a wheel with just about any brake. Great brakes allow you to apply as much stopping power as possible WITHOUT locking up a wheel. Disc brakes offer that. As for moving parts, the average hydraulic brake only has 5 or 6 of them (including the bits in the lever).
For me, though, that’s all moot. This is the Pac NW. Do you want to save your $50 canti’s, or your $800 wheels? Pushing a rubber block against the side of a weight-bearing structure in order to stop you vehicle is downright destructive. If we can make a frame out of 800 grams of Carbon hair, we can make brakes that don’t ruin our wheels.
That’s the big problem here: Rim brakes ruin wheels.
End of story.
Well again: There’s hydro vs. cable, and there’s disk vs. rim. Those two choices often overlap, but not always.
You can get cable-pulled disk brakes. In my experience: Your cables and housing won’t need as much adjustment; you’ll need to replace brake pads at about the same rate; and you’ll still need to replace the thing that the brake pads grind down — through three seasons, in these parts, of gritty wet-road slurry. It’s easier and generally cheaper to replace a thinned-down rotor rather than a cupped-out rim.
9watts, speaking only from a little BB7 experience, they are easier to install, set up and adjust than calipers or cantis. They modulate better than any rim brake I’ve ridden and lever effort is lower. The first time I grabbed an emergency handful I stoppied, but they modulated so well I didn’t endo. I haven’t replaced the pads yet but it looks easier than rim brakes, especially including adjustment. I agree with your test-of-time view but bike disks, in some form, will (continue to!) pass that test.
good to know. I appreciate your observations.
I started out with back pedal brakes, crappy sidepull brakes, even some that push down from above with a pad onto the top of the tire (I don’t know if they ever sold bikes with those brakes in the US). When I discovered mountain bikes with cantilever brakes that you could adjust, that would not always rub on one side, I was in heaven. Then came roller cam brakes, U-brakes. They were fine, but not as reliable when it came to adjusting them. After about 1990 I quit paying attention to the newest this or that. I still find the cantilevers fine, but I’m glad to learn there are other excellent successor designs out there.
Obviously I am more in 9Watts camp here, but I think Chainwhipped is focusing on something different than 9Watts and I. Speaking for myself, I don’t have any problem with folks that ride carbon and hydraulic discs and I actually think Di2 looks pretty cool, but I won’t be spending $$$ and I would think about how much it sucks that my bike won’t work with out a charged battery.
Generally I won’t be heard complaining about improved bike tech. What you will here me telling people is not to get hung up on the latest tech. That is because the only people that ask me about bikes are people who don’t know much themselves. Most of them I have to talk into spending even ~$700 on a bike much less $2,000. It’s not that there is anything wrong with the latest and greatest. Just that for any average person it isn’t necessary. Focus on a good fit, focus on the basics. Spend your money repairing an old bike and just ride. It the marketing blitz and bling that gets guys (yes guys in particular) more hung up on whether they have the best components actually riding a bicycle. I can’t tell you have many guys I’ve known that spend 4 hours gear geeking for every hour riding. Hey, if they enjoy it fine. But when it comes to promoting cycling, cables and rim brakes work just “FINE”.
BTW I’ve never worn out a rim, but of course, I won’t be spending $800 on a wheel either.
Out of curiosity, how the heck have you never worn out a rim? Are you one of those fixie riders that just brake with their feet?
The first question is serious, the second one not so much.
A couple of years ago I bought a folding bike and commuted on it for a winter. I wore out both rims in less than 1000 miles of commuting. Now granted, 20″ wheels will wear out around 50% faster than big rims, and my commute involves descending 800 feet down the steep side of the West Hills every damn night, so I do a lot more braking than some people. But still, that’s unacceptable when I can go many thousands of miles with discs and only change the pads a couple of times. In a decade of BB7 disc brake commuting (and mountain biking) I have still yet to come even close to having to replace a rotor.
This folding bike was my first rim-brake bike in quite a few years. And my last. I have since converted it to drums. I never want to own a futzy rim-brake bike again.
I think the blame there is likely to be on a cheap rim than the brakes. Maybe the pads too, but my guess is they were pretty cheap wheels.
Really? REALLY?? Are you sure that it wasn’t the increased rotational speed of the tiny wheels and the fact that there were rubber blocks pushed up against the sidewalls consistently in all weather conditions?
Friction plus road grit will wear down any rim. It really doesn’t matter what you spent on your wheels. The laws of Physics win every time. When that happens, the rim eventually gets so thin that it just blows out – usually while you’re on the bike. It can be a messy and dangerous failure.
And yes, mechanical disc brakes are fine, but they require MUCH more frequent adjustment.
1,000 miles (if accurate) is extremely few miles for wearing out a pair of rims. Yes, any rim will wear down eventually, but 1,000 miles is incredibly little.
They were pretty decent rims with fair amount of thickness to the brake track, with Kool-stop Salmon pads and V-brakes. I already mentioned the primary reason: I do an extreme amount of braking coming down out of the west hills in the worst grime every night (and I’m probably 200 pounds with a pack, not counting the bike). Not only is it a lot of braking, but I’m doing both short stretches of very hard braking, interspersed with longer continuous stretches of moderate braking, in which more crud tends to accumulate on the friction surfaces. Which I suspect may accelerate the wear exponentially.
Under the more easygoing conditions of a typical inner-eastside rider, I’m sure I would get thousands of miles out of a set of rims with rim brakes. But my extreme circumstances highlight this weakness of rim brakes, and for me they are unacceptable. Hey, if you like working with rim brakes and they do the job for you, enjoy them. But I find them fussy to set up and (too often) adjust, unreliable in extreme conditions and ultimately expensive in terms of trashed rims. Buh bye.
And V brakes put an incredible amount of pressure onto the rims compared to Cantis or dual pivot.
Eric,
Not sure if you understand I’ve BROKEN a lot of wheels. Specifically we are talking about wearing out a rim sidewall from grinding down the braking surface. If you keep your rims and pad clean this won’t happen very quickly. Touring rims, built stronger and where weight isn’t such a premium have thicker walls and will take longer to wear out. Also a lot of my riding was in better weather conditions that PDX winters, but a fair amount was in snow and mud.
Since I “grew up” I don’t ride fancy racing wheels except on nice days on nice roads. Mavic X719 rims in 36 hole will last one heck of a long time.
Back in 1979-’85 or so, when I was paying $$$ for “racing wheels” the wheels weren’t very strong and they bent before I ever came close to wearing down a braking surface. Same with MTB rims from ’84 on, the wheels bent from crashing long before braking surfaces wore out. By about 1990 I was a little smarter and wheels were better. I replaced the rear wheel on my 1992 Scott with a Mavic MTB rim, after a crash in 2004. Thousands of miles on the wheel, and 6 years of regular rain commuting in PDX before that. When it got bent it was pretty thin and needed to be replaced so I probably could say I wore out that wheel but it took me 12 years to do it!
I I do have original wheels on a couple of late 80s and early 90s racing bikes. Both of those bikes took a lot of miles the first 3 years, but mostl only in good conditions. I lived in the desert when they were new, and now they are for sunny day pleasure rides. Still, I’d guess over 10,000 miles on each of those bikes and the rims are fine.
For MTB disc brakes make much more sense, but it isn’t like rim brakes don’t work well enough. It’s an incremental improvement not anything earth shattering.
Just thinking, I have a set of wheels I built with Velocity Dyad rims when they first came out. (1997?) This is probably the most well used set of wheels I have ever owned. I built them as training / light touring wheels. They have been on several different bikes, used for long training, touring, and commuting. Currently they are on a foul weather training bike with fenders. I can’t accurately estimate how many miles on them but probably I put more miles on them each year from 1997 to 2011 than any other wheels I owned. So, may 40,000 miles? I started breaking spokes in spring 2011. 2 on separate climbs of Council Crest, then 1 on Forest Home Rd. in Camas and then 3 in one ride up Forest Home Rd. I then respoked the rear wheel completely as an experiment and challenge to my wheel building. It was perfectly round, but I found I had the spoke tension too loose on climbing. When I tensioned it up a bit, I barely managed to work the hop out and 2 nipples are bottomed out. But I’m still riding it. Anyway, point is that wheel was been worked over and worn out and the rim is hammered, but still rideable but the braking surfaces are not worn down badly at all. The surface doesn’t even have terrible grooves in it. Now I think there was maybe 2 years I rode those wheels in the rain regularly through the winter, but the wheels saw a ton of miles and were not pampered. With quality rims, it isn’t the braking surfaces that are going to wear out, in my experience.
All this not to argue there is anything wrong with discs. Just that it isn’t my experience that average people need disc brakes because of brake wear.
Sorry those are “AeroHead” not Dyads just for accuracy
No argument: If a braked rim is in gritty slurry less often, the service life of its sidewalls will extend. Mileage may vary, of course, with potential factors maybe including how much weight is on the bike, how often steep terrain is traversed, how faithfully traffic controls are respected, etc.
I never wore through a rim that way either, until Portland.
Very true. Go live in Arizona. Ride up and down Mt. Lemon every day, and your rims will last until the eyelets crack. The same rims won’t last a year riding up and down the ‘Ronde route. Not unless you’re cleaning your rims and brake pads after EVERY wet ride, which almost nobody does.
There does come a point at which well-proven and more “aggressive” technology has a place on a bicycle. If we look at what’s happening to road bikes in recent years, the industry has finally stopped trying to lose weight. Instead, they’re looking for ways to actually benefit the rider: improved power transfer, aerodynamic improvements, better brake control, Tubeless tires (finally). It all points to a more efficient bike.
The really amazing thing is how slowly real improvements have been made with road and ‘cross bikes while the curve has been so sharp in MTB development – Aerodynamics aside, anyway. It seems that since the late 90’s, all that road bike and part makers have done is try to figure out what else they can make out of Caron Fiber, overlooking any potential real improvement. Between Tubeless Tires and real brakes, road bike and part makers are at least a decade behind their off-road counterparts.
“it isn’t like rim brakes don’t work well enough.”
I’m a mountain biker, and I don’t know ANY fellow mountain biker in the Pacific Northwest who would agree with the above statement, nor that discs are merely an incremental improvement over V-brakes.
Not one. And I ride with a lot of retro-grouches (such as myself in many respects) who eschew at least full suspension, and in many cases any suspension at all, and many who also prefer not to fuss with that newfangled derailleur technology, especially in the winter. And also to be clear, I’m an old-school cross-country rider, not a downhiller, shuttle junkie or “all mountain” rider, same as most of the people I ride with. But everyone – and I mean EVERYONE – rides with discs, especially in the cruddy season, and would never go back.
I guess I’m the only one in the whole Pacific NW. Maybe I should try some.
Can’t imagine you would go back once you do!
You people are funny.
Chainwhipped –
“Rim brakes ruin wheels.”
Eric –
“how the heck have you never worn out a rim?”
My Magic Hat –
“Friction plus road grit will wear down any rim. It really doesn’t matter what you spent on your wheels. The laws of Physics win every time. When that happens, the rim eventually gets so thin that it just blows out.”
I haven’t biked 40,000 miles in fifteen years like Paul-in-the-‘couve, but I’ve biked many, many thousands of miles and not only have I never blown out a rim, I’ve never had any rim issues related to wear from brake pads. I thought it was the pads that you replace, not the rims. It has worked great for me.
Now my wife’s bike, she goes through rims and pads like nobody’s business. I’ve never figured that out. I think what some of you rim-brake snobs aren’t taking into account are differences in how people ride.
Oh, agreed! In my case, the way I ride includes a helmet-cam — and I wouldn’t bother to cam if I were just going to document my own lawbreaking.
Please comment on your own policy toward stop signs and other traffic controls for which compliance is brake-dependent. Not to judge; just curious now.
Paul, you can get new mountain bikes for under $500 with discs these days, some even have hydro discs. I think the “techies” are saying that the price is going to go down and we’re going to see these things become standard in the future. The same way that it happened in mountain biking.
hmmm… I have an irrational Peugeot fetish (Check) Own a couple of classic Schwinns one a primary rider (Check). Still riding down tube shifters (check) No Carbon, no discs, (Check) ooops I’m obsolete. Oh well I still like riding. Oh, and I totally dig modern LED lights and rear mechs that actually shift and ramped cogs on my cassettes. And I’d never go back to flat prone tires that wore out in a month.
hydro tech question: Have you tried DOT 5 fluid in your bike’s brakes? How did that work for you?
(disclosure: I love DOT 5 in older car brake systems.)
In 45 years of riding in Florida I never wore out a rim, but I am not in Florida anymore and I’m not buying as many bikes or wheels. I suspect that I may want to switch to discs on my current bike so when I built it I made sure that the frame and fork have disc tabs.
Still haven’t seen an answer to my earlier question about what exactly was the failure mode for the SRAM brakes. Anyone know?
What I read implied to me that in the unusual cold, the fluid seals failed to stay pliable and/or they contracted, allowing fluid to escape. That’s roughly the equivalent of too much cable slack, so levers were bottoming out without accomplishing much braking.
That’s how I interpret it, too (would like to know authoritative version), but I’d say it’s more like a cable clamp slipping. Slack, whether cable or hydro, could come from any number of things but going from adjusted to slack in the course of a race…that has a specific failure mode.
Yes, what Bill said, gasket failures in the levers.
Oh? Any more? (Bill said “fluid seals” which could be either master or slave cylinder, and which I’d interpret as o-rings on pistons, whereas “gasket” is more about flat surface seals like on the resevoir.)