you've really got it in for disc brakes huh? repeatedly chucking in the mamil reference just sounds like trollage.
I've not got it in for disk brakes in general, they'd be fine (if overkill) for a commute or touring. But I still think they're overkill for a problem that doesnt really exist.
The mamil referance I'm just refering to that section of the bike buying public who buys £2k bikes while the tours on telly, tells everyone who'll lsiten they rode 30km at the weekend, then put's it in the shed only to re apear on ebay in 18 months time. £600 di2 brakes are tailor made for them*.
On my neglected commuter rims lasted a couple of years tops, pads didn't last long at all and when I switched to grittier NCN routes pads lasted a week and rim wear accelerated. Disc brakes are definitely a good move commuter wise
Agree entirely, commuter bikes fine, road/race replica bikes (which £600 Di2 brakes are clearly aimed at), why?
*and people who take cross seriosuly, but I suspect that they'll be a minority of who ends up buying these.
I've not got it in for disk brakes in general, they'd be fine (if overkill) for a commute or touring. But I still think they're overkill for a problem that doesnt really exist.
I'd say a premium for improved brake modulation and reduced rim wear is worthwhile - the question is only how much extra I would be prepared to pay.
I've not got it in for disk brakes in general, they'd be fine (if overkill) for a commute or touring. But I still think they're overkill for a problem that doesnt really exist.
Drum brakes worked fine on cars, why have they all got discs now?
V-brakes worked fine on MTBs, why have they all got discs now?
There are loads of benefits to discs:
takes the braking away from the rim so you can have lighter/stronger/stiffer/more aero rims without the weight penalty or the structural integrity issues.
allows much more intricate hose routing - hydraulic hose can be fully internal, can turn corners which cables can't.
much less servicing required - maybe a bleed and pad change once every 18 months or so.
and the usual one: more consistent stopping power, more modulation
new technology innit, always comes out at the top then filters down. As others say, it's probably the future, but maybe still a bit portly at the moment for mass uptake. I'd guess there'll be more uptake for winterbikes once it comes down to lower groupsets then, once they're lighter and wheel tech builds on the advantages, the race bikes too. But I'm just guessing, who knows what goes on in a roadie's head 😉road/race replica bikes (which £600 Di2 brakes are clearly aimed at), why?
Drum brakes worked fine on cars, why have they all got discs now?
Because generaly car's with drum brakes had <30hp and weighed <500kg. Modern cars are at least 2x the weight and 3x the power. I know I mentioned MAMILS but calling them too fat for calliper brakes is just offensive 😛
Donk, both, most mileage is commuting, but i currently have a 16mile pan flat rural commute, there are a couple of lights where i might have to use the brakes!
As for your comment about what goes on in roadies head, will it make me faster!
Brakes, well they are designed to make you go slowly, so why spend money on them?
tyres, wheels, gears, frames, etc things that make you go quick is where you spend money.
My brakes work well enough, are reasonably cheap, are reliable and, if we go by the standard threads, don't need a weekly bleed!!!!
I have to say I kind of agree with TINAS on this now to a certain extent, the prime markets right now for a hydraulic STI are Drop-bar commuters, CXers and possibly some Tourers; all looking for less maintenance, servicing, better reliability and sensible pricing, but also not really the target group for Di2 either so as a product Di2 shifting/hydraulic braking STIs don't really make that much sense IMO
Serious roadies will be sticking to rim brakes for the forseeable future and aspirational "MAMIL" types will seek to emulate their hero's, and hence will adopt Di2 Ultegra/Dura Ace on High price point bikes, but won't want discs cause it's not what the pro's are using...
takes the braking away from the rim so you can have lighter/stronger/stiffer/more aero rims
Disc rims can be lighter, but add in the weight of the rotor and heavier hub and they are pretty much the same. No radial lacing on wheels so spokes are longer (less aero?), longer hose routing, then add in the extra material to locally strengthen the frame and fork and suddenly discs become a much heavier option than rim brakes.
allows much more intricate hose routing - hydraulic hose can be fully internal, can turn corners which cables can't.
I’ve never had a problem with any bike routing the brake cables, road bike cable routing is really quite straightforward.
much less servicing required
Seriously? I guess you’ve never seen the sticking pistons, contaminated pads, brake fade, boiling and warped rotors threads which crop up on here regularly?
One of the main drawbacks though is that from an aero point of view they are gash, the caliper (particularly the front) is basically a big lump of metal exactly where you don’t want it. I think it was Cervelo that did some testing and found that they were terrible.
irelanst - MemberDisc rims can be lighter, but add in the weight of the rotor and heavier hub and they are pretty much the same. No radial lacing on wheels so spokes are longer (less aero?), longer hose routing, then add in the extra material to locally strengthen the frame and fork and suddenly discs become a much heavier option than rim brakes
You're moving the material needed to strengthen the frame/fork, not adding it. Slightly longer hoses, but much lighter, as they don't have a steel cable in them.
As for the aero side, nobody's tried to address that for road discs yet - integrating them better with forks will improve that.
On the aero thing, start with a rim that is 50mm deep design it for disc brakes an design it for rim brakes and how much difference is there actually going to be? you might be able to remove a little mass as there is no wear from braking, but you can't remove that much as the wheel still has to hold a tyre at upto 150psi. It still has to be able to cope with minor potholes etc.
I don't actually see any slightly deep wheel getting lighter, infact i can see them getting heavier as the hub and spokes have to be speced to take the extra load.
As for the aero side, nobody's tried to address that for road discs yet - integrating them better with forks will improve that.
on the aero thing, a rim that doubles as a braking surface will be better than having another surface bolted to the hub. Remember the UCI rules on farings and non structural components.
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make a disc this aero?
And it's not really "Just" £600, comes to ~£880 once you bung another £280 on for their wheels;
And don't forget you also need their really cheap electronic rear mech and front mech too...
You're moving the material needed to strengthen the frame/fork, not adding it
No you're not, the loading on a disc caliper is far higher than on a rim brake and is transmitted into a single fork leg / stay. Using a fork as an example, in a rim brake the braking forces are transmitted directly into the fork crown which is stiff and supported by the headset, in a disk brake almost the entire length of the fork leg has to withstand the torque generated at the caliper.
Because generaly car's with drum brakes had <30hp and weighed <500kg. Modern cars are at least 2x the weight and 3x the power.
Aside from your wild exaggeration, speed limits remain the same, and modern cars can stop in a far shorter distance than they did BITD.
The weight arguments are a bit of a red herring TBH, it must be possible to build a disc braked road bike at the magic 6.8kg mark (IMO) then neither method of deceleration presents any real weight advantage in competition...
The Aero points have more merit but are still debatable IMO.
While a chunky, angular MTB caliper might well be an aerodynamic nightmare, that shape can be monkeyed with and improved upon no end, and of course once you remove the rim brake caliper from the fork crown and top of the seat stays you can start to look at re-profiling those areas for some co-responding aero improvements perhaps, all of those images above seem to show a consistent effort being made to "blend" a rim brake and minimize it's apparent Aero disadvantages, so the current preferred solution still ain't "perfect" clearly...
Realistically though the last lot you'll persuade are the serious Amateur and Professional roadies, the closest you might get right now is talking them them into trying disc braked "Winter bikes" maybe?
But then these aren't the only people who buy or ride road bikes.
Realistically though the last lot you'll persuade are the serious Amateur and Professional roadies, the closest you might get right now is talking them them into trying disc braked "Winter bikes" maybe?But then these aren't the only people who buy or ride road bikes.
which leads neatly to a point made earlier, why Di2 Disc brakes, how many roadies are going to have Di2 on the winter hack? How many commuters tourers are going to use Di2?
Mind you the same applies to SRAM, how many are going to buy the red22 discs? I can see some people buying the hydro calipers just not the discs.
with disc brakes, a fork has to be stiffer, which will impact ride quality no matter the argumuments about carbon 'property placement'. plus most roadie tyres aren't up to reaping the power benefits of a half-decent disc brake, and a decent road rim brake doesn't lack modulation.
so here's how I see it: Mr MAMIL buys latest hot-snot bike with £600 hydro brakes. crashes first time it spits. Hey presto, cheap hydrau-compatible levers available on the secondhand market without the need to wait for trickle-down to 105 (or sora, which is more realistic in my case).
everyone's a winner!
with disc brakes, a fork has to be stiffer, which will impact ride quality no matter the argumuments about carbon 'property placement'. plus most roadie tyres aren't up to reaping the power benefits of a half-decent disc brake, and a decent road rim brake doesn't lack modulation.
💡 that is why they are pushing 25mm tyres, nothing to do with performance, convince people that the next bike has to have bigger softer tyres and discs, you hide the fact that the bike is less comfy etc.
One other point tinging discs!!! every set of disc brakes i have come across will at some point rub!!!!!!
mrmo - Member...that is why they are pushing 25mm tyres...
get you, posh mr 'la-di-da' with your smooth new tarmac, and predictable road surfaces.
round 'ere its 2000 year old cobbles, and potholes so deep you can swim in them.
our potholes are so big, they've got potholes in them.
it's all about 28's now.
(except they don't go through the brake callipers, which is another reason why discs are great)
Loving all the condescending talk about commuters and MAMILs. Well done.
Good to see it's not just mountain biking that can be snooty and elitist. 😕
fwiw I am a commuter and having just bought my first road(ish) bike at 38 and opted for a comfortable CX frame with 28mm tyres and discs I guess I qualify as a MAMIL too.
The uptight "[i]road bikes must only ever be used for racing or training to race - never for transport or, heaven forbid, fun[/i]" crowd should try to relax a bit. Maybe straighten out that hunch a bit. It's all "riding bikes" and it's all good.
Discs suit me. (BB7s on my bike). I couldn't care less if the aerodynamics and extra weight mean I'm pushing an extra half watt - or if i have one too many spacers under my stem. Because I ride for pleasure not trophies.
that is why they are pushing 25mm tyres, nothing to do with performance, convince people that the next bike has to have bigger softer tyres and discs
Except almost all the riders on the tour this year are on 25c...
[url= http://road.cc/content/news/86495-tour-tech-2013-andy-schlecks-trek-domane-6-series ][i]Like a lot of other teams Leopard Trek have largely gone for 25mm tyres and that's what Schleck has on his Bontrager Aeolus 3s too.[/i][/url]
and Corsica's roads looked pretty smooth to me?
As a side note does anyone ignore all the UCI rules and come out with 5kg* aero faring-ed normal shaped** bikes for your average punter? Dunno if there's a business case, I assume the minted ATGNI guys want race replicas and the serious guys will need race regs bikes. But 99% of my road riding is solo and not in any competition and I'm sure I'm not alone.
*not that I could afford a bike that weighed 5Kg, just hypothetically speaking here
**I know recumbents and preying mantis bikes are quicker but bit not practical on busy roads.
you posted the pic, we [b]know[/b] you are 😉GrahamS - I guess I qualify as a MAMIL too.
Fair point D0NK 😆
D0NK, commuting to work on his mtb...
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As a side note does anyone ignore all the UCI rules and come out with 5kg* aero faring-ed normal shaped** bikes for your average punter?
They are already available, triathalon bikes, designed [s]to go fast[/s] for loners 😆
As for the OP, I'd buy a bike that had them over one that didn't, though I wouldn't upgrade the one I have by putting them on.
Except almost all the riders on the tour this year are on 25c...
and at the Giro most were on 23's... and i have seen a few comments that 25's aren't as common as is being made out. Consider also that most pros are on tubs not clinchers.
GrahamS, no issue with commuters, i am one, my only issue is whether Di2 is the place to start with disc brakes and generally not convinced they offer enough advantages compared to calipers.
Discs on MTB no brainer imo, better mud clearance for a start. On a road bike, higher speeds, more faff, etc.
GrahamS needs a hug. But not while he's in his lycra please 😉
btw I hope 38 doesn't qualify as middle-aged!
btw I hope 38 doesn't qualify as middle-aged!
as someone at work said to me,
age at death for a man is 85,
divide this by three, so you have young, middle aged and old.
your young till your 28, middle aged till 56 and then old.
As the average male life expectancy in the UK is 78 then 38 is close enough to be called middle-aged I would say.
your young till your 28, middle aged till 56 and then old
NNNNNNOOOOOOOOOOOOOO!!!!!!!!
😥
Tomhoward
DOB 23.3.85
I'd get them if they were cheaper. I hate my road bike brakes, they are shit. Ok if you are braking gently in the dry but coming down a 1:4 in the Valleys approaching a roundabout in heavy rain, they do pretty much nothing.
tomhoward - Memberyour young till your 28, middle aged till 56 and then old
NNNNNNOOOOOOOOOOOOOO!!!!!!!!
Tomhoward
DOB 23.3.85
+1
DOB 28-11-1980
DOMA 28-11-2008
[desperation] okay, in Mayan culture, I believe, you don't pass out of childhood until 33 and you're still not a man until 52. if average age of death is 78, then you are not into your second trimester of manhood until 60yrs 8months.
congratulate me, I stop being a child this year! [/desperation]
They are already available, triathalon bikes, designed to go fast for loners
Actualy that brings up another point. MTB'ing is a solo activity, even in a group you ride far enough apart that you're not influenced by the person in front braking.
Roadies travel in very close groups, I'm not sure I'd want the guy in front to have significantly more powerfull brakes than everyone else!
Roadies travel in very close groups, I'm not sure I'd want the guy in front to have significantly more powerfull brakes than everyone else!
which i believe is the UCI standpoint at the moment. Think of track bikes, having no brakes is safe as long as no one has any brakes.
fwiw I am a commuter and having just bought my first road(ish) bike at 38 and opted for a comfortable CX frame with 28mm tyres and discs I guess I qualify as a MAMIL too.
Nah that's my whole point, you should be core target market for hydraulic road discs! but it looks like your not...
instead they're after "MAMILs" who will be looking at Ultegra/DA to decorate their composite ego-wagons, rather than the Gent/lady wanting an efficient, sensibly priced, minimal maintenance, all weather, road commuting bike, using braking technologies proven to work over the last decade and a half on MTBs...
As a "flagship product" Shimano have managed to miss that key market by a country mile, overpriced and aimed squarely at early adopters of extra blingy road gear, who ain't too bothered by discs unless they see them on Cav's bike first...
I have no doubt that a more practically priced and designed product will be along before too long, but this is not the best start...
which i believe is the UCI standpoint at the moment.
But one which makes no sense given they allow hydro rim brakes (wasn't Cav running them?)
And an odd argument given how many people claim that discs offer no braking advantage.
I reckon the UCI will [i]eventually[/i] allow disc brakes.
Probably 5 years after they become standard on low-end road bikes 😉
thisisnotaspoon - MemberRoadies travel in very close groups, I'm not sure I'd want the guy in front to have significantly more powerfull brakes than everyone else!
On the flip side, I'd like the bloke behind me to be able to stop quick if he needed to
Think of track bikes, having no brakes is safe as long as no one has any brakes.
Imagine how much fun the TdF would be if no one had brakes !! 😀
The thing with the peloton safety argument is that many folk also ride on their own on unclosed roads with other traffic, where being able to stop promptly when needed can be very useful!
I don't know [s]a lot[/s] anything about tri bikes but got the impression they were ridiculously stiff and had brakes and gears in funny places, perfect for aero tuck on closed roads, not so much on the A6 through swinton 🙂They are already available, triathalon bikes
but I guess maybe we are back to "it's the rider not the bike", in this case a good position will save you a lot more watts than an aero bike.
Think of track bikes, having no brakes is safe as long as no one has any brakes.
Have you ever been on the track? 😀
GrahamS - MemberI reckon the UCI will eventually allow disc brakes.
Probably 5 years after they become standard on low-end road bikes
Given that Shimano & SRAM are going ahead with launching them, I think you can be reasonably sure that Pat McQuaid has been handed sufficiently large envelopes to ensure their approval
Roadies travel in very close groups, I'm not sure I'd want the guy in front to have significantly more powerfull brakes than everyone else!
Never had a problem with this (has anyone?) despite training in numerous chaingangs with BB7's.
Theres a much bigger braking differential between aluminum and carbon rims in the wet.
