Disc brakes

Birdthom

Looking at the news, it seems we're not far from discs being sanctioned for racing by the UCI. They're clearly an advance in tech terms, fine for the pros, and great for training etc, but I'm sot sure how this is going to work out for your average club racer. I'd love discs in time, but I'm not about to rush out and replace my bikes. I don't want to be forced to upgrade my bikes, but unless everyone is running the same brake technology it's going to get very sketchy in amateur bunch races.

Any idea how this is going to work out for us lot?

kajjal

The main problem apart from cost is a mixed group of riders some with discs and some with rim brakes is potentially dangerous. Those on disc brakes can brake harder and later which may cause rim braked riders to go through the back of them but this would only occur for sudden braking.

imposter2.0

I don't think braking force is the issue - I can already lock the wheels with calipers if needs be. I doubt if it will make any practical difference in races.

wallace_and_gromit

Imposter wrote:

I don't think braking force is the issue - I can already lock the wheels with calipers if needs be. I doubt if it will make any practical difference in races.

It might do in wet races. Disc brakes are nigh on impervious to rain whereas conventional ones aren't.

I think their main market will be the MAMILs in the Alps etc. who aren't so good at descending, as you can descend "on the brakes" without risking overheating rims and blowing off tyres.

rickwiggans

Wallace and Gromit wrote:

Imposter wrote:

I don't think braking force is the issue - I can already lock the wheels with calipers if needs be. I doubt if it will make any practical difference in races.

It might do in wet races. Disc brakes are nigh on impervious to rain whereas conventional ones aren't.

I think their main market will be the MAMILs in the Alps etc. who aren't so good at descending, as you can descend "on the brakes" without risking overheating rims and blowing off tyres.

You're missing the point a bit here WRT descending. The greatly superior modulation characteristics of discs (hydraulic anyway) mean that descending can be considerably faster, since the braking point can be later, and the fine control is much improved. The "I can lock the brakes with calipers" is an over-rated argument. The point is you can go into corners considerably faster with less chance of locking up. The main market, within 18 months or so, will be driven by the pro-peleton, who are strongly arguing for UCI to approve them.

imposter2.0

Just to be clear - I'm not against disks. I just think the general benefits are over-stated and I don't buy the 'more modulation' argument - it may be technically correct, but in practical terms, I suspect it will be meaningless.

Also, it's rare that a road race or crit is won by the rider with the best brakes, so in 'race performance' terms, I see the benefits as being minimal to non-existent.

roger_merriman

Imposter wrote:

Just to be clear - I'm not against disks. I just think the general benefits are over-stated and I don't buy the 'more modulation' argument - it may be technically correct, but in practical terms, I suspect it will be meaningless.

Also, it's rare that a road race or crit is won by the rider with the best brakes, so in 'race performance' terms, I see the benefits as being minimal to non-existent.

MTB's are fairly easy to brake and quite hard on greasy/slippery surfaces without locking brakes, sure they are a established tech while for road its new tech, but even so all things being equal you its easier to brake later/harder with out locking.

Its a advantage some of the bigger European races do have some big descents, people have most certainly lost and gained time their.

I suspect it will be and is more of a game changer for the fast commuters mind you.

Birdthom

Imposter wrote:

I don't think braking force is the issue - I can already lock the wheels with calipers if needs be. I doubt if it will make any practical difference in races.

People always say that about upgrading brakes on cars, but the reality is that better brakes allow you to 'threshold' brake much more easily and effectively, so your stopping distances are reduced hugely. I expect the same is true for bikes. Don't think I'd want to be sitting on someone's wheel in a wet circuit race if they had discs and I had carbon rim brakes :shock:

guinea

Anyone who's ever ridden a mountain bike with hydraulic brakes knows that rim brakes are poor in comparison.

Anyone who's had to do an emergency stop in the wet on rim brakes knows their limitations.

Discs are a good thing for all weather use. As a heavy guy who rides in all weathers I can't lock up the front wheel any of my rim brake bikes. On large descents I can get juddering from the crappy modulation, but I've never been able to pull the brakes hard enough to lift the back wheel.

With discs all the power is there. The only limitation is your choice of tyre.

kajjal

As above discs give power and modulation without being affected in the wet. It is not about locking up wheels but about having very fine control over much more powerful braking. If you are heavy or it is wet there is no comparison.

imposter2.0

Nobody is arguing that discs don't offer a better braking system than rim calipers. The issue is whether it actually matters in 99% of UK amateur road/circuit races. I personally don't think it does. Other than dragging the rear slightly in the bunch from time to time in order to maintain a safe gap with the wheel in front, I don't recall using my brakes much, if at all.

ongej

Imposter wrote:

Nobody is arguing that discs don't offer a better braking system than rim calipers. The issue is whether it actually matters in 99% of UK amateur road/circuit races.

Erm.. but doesn't this apply to carbon frames and zip 404s that commonly grace the amateur races? We get because we want...

ugo.santalucia

Discs and racing... not sure!
They have been allowed in cyclocross for a few years now and despite the manufacturers pushing for them, nobody use them. Nys doesn't use them, Stybar doesn't use them... end of the story. Eventually Shimano will force them to use them by contract, but that's not exactly saying "they are better".

In road cycling it's even worse... try to change a rear wheel with a rotor... sometimes it takes a couple of minutes of trying to jam the damn thing in the slot, not exactly ideal if you puncture during a race.
Yes, coming down the Galibier in the rain, you would feel safer, but Pantani showed it is perfectly possible to fly down with rim brakes and if you can't descend, disc brakes won't make you into a new Savoldelli.
How many races per year would actually see you better off with discs? My guess is 2-3 times.

So, despite being the greatest fan of disc brakes for road bikes, I don't think they belong to the world of racing and if they get there, it's only by manufacturers pressure, not because riders actually want them

Pross

I'm surprised the pros are pushing for discs, I would have thought it will make changing wheels slower and the risk caused by that would more than offset any benefit gained by improved braking.

DeVlaeminck

We already have people on carbon rims with relatively poor braking mixed in with people with alloy rims and rims with special brake tracks to improve braking, I haven't noticed much of an issue there. There must already be big difference down to rider ability too. I'm with Imposter, I don't see it making much difference in terms of safety.

gazman428

Coming from mtbs to roadbikes i'amazed how shite the brakes are. Soeties your pulling that hard in the wet that if the wheel does slip you cant release it quick enough because your squeezing that hard.

I deffo want discs on my bikes

imposter2.0

There's gonna be an awful lot of redundant wheels on the market in the next few years - not to mention what all the pro and pro-am teams will do with theirs....

cycleclinic

I'll take some of those pro team wheels if they don't want them anymore. As for disc and rim braked bikes in a race if you know the limits of your brakes and tyres and how your bike behaves (if you don't don't race) then you should be able to adjust. Rim brakes under certain circumstances may put you at a disadvantage but it will depend on rider skill too.

Silly Old Hector

ugo.santalucia wrote:

Discs and racing... not sure!
They have been allowed in cyclocross for a few years now and despite the manufacturers pushing for them, nobody use them. Nys doesn't use them, Stybar doesn't use them... end of the story. Eventually Shimano will force them to use them by contract, but that's not exactly saying "they are better".

In road cycling it's even worse... try to change a rear wheel with a rotor... sometimes it takes a couple of minutes of trying to jam the damn thing in the slot, not exactly ideal if you puncture during a race.
Yes, coming down the Galibier in the rain, you would feel safer, but Pantani showed it is perfectly possible to fly down with rim brakes and if you can't descend, disc brakes won't make you into a new Savoldelli.
How many races per year would actually see you better off with discs? My guess is 2-3 times.

So, despite being the greatest fan of disc brakes for road bikes, I don't think they belong to the world of racing and if they get there, it's only by manufacturers pressure, not because riders actually want them

+1

markos1963

I don't understand the analogies between MTB and road. Yes disc brakes make sense on MTBs with the need for predictable braking in varying conditions and the fact they have wide grippy tyres. Road bikes are governed by the amount of tyre grip they have. I do believe in the 'I can lock up callipers' aspect but only in the dry. This is the only area I think a road bike with discs will have an advantage over rim brakes. However, in the wet on skinny road tyres do you really want to be out braking a field of 4th cats?

cycleclinic

I don't think from your comment you have used disc brakes much. On the road predictable braking in the wet is very useful disc brakes give you that. You modulate the brake to prevent lock up. Given tomorrows race is going to be very damp I wish I had disc brakes but I don't. You brake with the rest of the group not to out brake them. More braking torque is never bad. If you built a race car for would you fit drum brakes to it - of course you wouldn't you'd fit disc brakes and calipers with enough braking torque to safely stop you from high speed without brake fade.

In a group riders will brake at similar rates they have it's a group. Right now different bikes given differing rider weights have big difference in braking rates.

markos1963

thecycleclinic wrote:

I don't think from your comment you have used disc brakes much. On the road predictable braking in the wet is very useful disc brakes give you that. You modulate the brake to prevent lock up. Given tomorrows race is going to be very damp I wish I had disc brakes but I don't. You brake with the rest of the group not to out brake them. More braking torque is never bad. If you built a race car for would you fit drum brakes to it - of course you wouldn't you'd fit disc brakes and calipers with enough braking torque to safely stop you from high speed without brake fade.

In a group riders will brake at similar rates they have it's a group. Right now different bikes given differing rider weights have big difference in braking rates.

Actually I do about 5k miles a year on a bike with discs so I am fully aware of their properties. If you re read my statement I did say in the wet discs on a road bike make sense. Having come from motorbike racing I am also aware of modulation. Car analogies don't really work as you can't fall off a car in the same way. I still think that in amateur racing races aren't won by braking. If you are arguing for discs on safety grounds then I would probably agree with you.

mamba80

I don't care about whether discs are better/safer/less safe or not, discs on a road race bike just look wrong and I hope the uci keep them out of pro racing.
Someone made the comment about all these 2nd hand rim brake wheels? what about all these old style 130mm frames that will become worthless? (at least until the launch of an Erioca style sportive for carbon bikes with 9/10sp and rim brakes) this is just another marketing ploy by the manufactures to get us to buy more kit, that we don't really need.
This is perhaps a bad time to be buying wheels/frames or bikes.

ugo.santalucia

mamba80 wrote:

I don't care about whether discs are better/safer/less safe or not, discs on a road race bike just look wrong and I hope the uci keep them out of pro racing.
Someone made the comment about all these 2nd hand rim brake wheels? what about all these old style 130mm frames that will become worthless? (at least until the launch of an Erioca style sportive for carbon bikes with 9/10sp and rim brakes) this is just another marketing ploy by the manufactures to get us to buy more kit, that we don't really need.
This is perhaps a bad time to be buying wheels/frames or bikes.

Agree on the race part, as I pointed out earlier... but I think the two technologies can live together. Rim brakes for the racing end of the market, disc brakes for the recreational market up to the mid tier sportive market. You're not confident riding those carbon clinchers downhill? Get a disc brake bike... you want to race? Get a rim brakes bike. Makes perfect sense to me and that's the direction the market is going, as I understand.

Monty Dog

It will take a year or two - likely to start at World Tour one year, then Pro-Continental the next. I was playing around with a disc-shod road bike 10 years ago - with carbon wheels it's a no-brainer. Some of the scariest racing I've experienced was a hilly RR in the pouring rain with carbon wheels - 30mph descent with a 90 degree bend at the bottom. For CX, it really depends on the course and conditions - tyre choice is far more critical than brakes IME - I'm sticking with cantis as I've got 3 pairs of tubular wheels.

wallace_and_gromit

ugo.santalucia wrote:

...disc brakes for the recreational market up to the mid tier sportive market.

This must be the market for disc brakes. I will never forget the sound of exploding tyres coming down the Glandon in last year's Marmotte. It was like a war zone! High temperatures, carbons wheel, a busy road and inexperienced riders is not a good combination!

kev77

I have been through numerous quick sportives on my Disc shod Cannondale Roadie ( Synapse Disc ) currently looking at Disc specific carbon rims

Descending in the wet was far superior IMO than those with normal calipers, the only downside this year I was unable to race on it due to the Disc ruling

Eg. on my TT with carbon rims doing a wet TT with cork pads is terrifying trying to scrub speed!

ha ha

DeVlaeminck

Wallace and Gromit wrote:

ugo.santalucia wrote:

...disc brakes for the recreational market up to the mid tier sportive market.

This must be the market for disc brakes. I will never forget the sound of exploding tyres coming down the Glandon in last year's Marmotte. It was like a war zone! High temperatures, carbons wheel, a busy road and inexperienced riders is not a good combination!

Was this, errr, towards the back end of the field ? I did the Marmotte last year and I didn't hear any tyres exploding. Be interesting if it is an issue of novices who can't descend.

wallace_and_gromit

DeVlaeminck wrote:

Wallace and Gromit wrote:

ugo.santalucia wrote:

...disc brakes for the recreational market up to the mid tier sportive market.

This must be the market for disc brakes. I will never forget the sound of exploding tyres coming down the Glandon in last year's Marmotte. It was like a war zone! High temperatures, carbons wheel, a busy road and inexperienced riders is not a good combination!

Was this, errr, towards the back end of the field ? I did the Marmotte last year and I didn't hear any tyres exploding. Be interesting if it is an issue of novices who can't descend.

I don't know to be honest. I didn't note the numbers of those by the roadside as I decended past them to check their names and previous form when I finished! They were all in the 730am or 7am start wave though.

The only rider I do know who was so afflicted was a friend who was probably on for a start to finish time (i.e. including Glandon descent) of sub 8:30 based on my efforts and how much faster he was than me, so definitely not back end of the field fodder.

This merely emphasises my point. For most UK (and probably Dutch, Danish etc.) riders, practicing Glandon-style descents in heavy traffic in high temperatures isn't that easy, so such riders may only find out their decending technique isn't right when their tyre explodes. It's easy to say "Don't ride on the brakes", but if you need to slow down, overtake leaving little room or risk a blind corner to avoid a slower rider then braking may be the only option.

Thus, the the obvious "demographic" to which disc brakes should be marketed is the serious riders in north European countries with very few long desecents. In an ideal world everyone would be able to descend properly, but just like most Brits are crap at skiing because there's little opportunity to practice in the UK, better equipment can compensate for a lot of technical deficiencies, making it more enjoyable for the technically deficient and safer for everyone else.

DeVlaeminck

This is a difficult one because I admit when I first went out to the Alps to do the Marmotte I was worried about this having read similar posts. However having ridden the Marmotte three times all in hot conditions I've yet to see or hear a tyre blow off the rim and when we talked about it the only time any of us had seen it was once coming off the Alpe in the week building up.

I do think you'd have to be a pretty poor descender for it to happen. Not riding on the brakes doesn't mean not braking - it means don't drag your brakes for extended periods of time. So long as you are happy at 40mph you can pretty much just freewheel then brake for the corners if you wanted to - there is no need to be on the brakes the whole way down. If you get a slow rider in front of you just go past them. I was worried about the Glandon descent but when I rode it I thought it was no worse than most descents in Derbyshire - just longer and without the potholes and gravel - I really enjoyed it ! That said one of our lot did manage to wipe out on it (he was doing the 2 day Marmotte so was on his own) but he was a novice and it is easy to get carried away with things.

So for anyone reading this who hasn't ridden out there before - don't worry just lower your psi a bit, don't fit loose tyres but mostly just don't drag your brakes the whole way down.

wallace_and_gromit

DeVlaeminck wrote:

So for anyone reading this who hasn't ridden out there before - don't worry just lower your psi a bit, don't fit loose tyres but mostly just don't drag your brakes the whole way down.

I certainly wouldn't want anyone to think that exploding tyres is particularly frequent. There must also be an element of bad luck involved. I've done the Marmotte three times without incident on the descents, and I'm pretty sure I'm not a good/proper descender.

But the risk of overheating your tyres and causing them to explode is definitely non-zero, which is why there must be a market for disk brakes given the natural desire of folk to be safe without taking ridiculous measures.

I did a lot of MTB riding in the mid 90s using nothing more than V-brakes, which were the in thing at the time. Pretty much everyone else did as well, and the vast majority of rides ended quite safely, but this did not stop disk brakes taking over due to being better, however marginally. (I guess the benefit on MTBs from disk brakes is higher than on road bikes though.)