FAO disk brake lovers...

davis

meanredspider wrote:

All I can say about discs on a road bike is don't knock it until you've tried it. Personally, I'm struggling to see the downsides. I don't (yet) see the point of hydraulic brakes on a road bike. BB7s work just great and need minimal maintenance. I'm very confident that this Colnago is just the first of a series of big names to bring out discs and, in time, discs will be the norm and we'll all think how quaint it was when bikes squeezed bits of rubber against the wheels to stop.

This. From getting used to the discs on my Pompetamine (which has horribly heavy wheels made of girders; should be better when I put some nicer ones on) to going back to my Roubaix.... The braking on the Pomp is just better, even with well-adjusted callipers, clean true rims and Kool Stops on the Roubaix. It just is.

bails87

supersonic wrote:

This may be of interest:

http://www.ne.jp/asahi/julesandjames/ho ... k_release/

Though I would say aerodyndamics are one reason for the position.

On page 1

Sketchley wrote:

nicklouse wrote:

why did they not put the brake on the front of the fork?
it would have eliminated possible wheel issues with lightweight Ti carbon Qrs.

Are these the same "issues" mentioned here http://www.ne.jp/asahi/julesandjames/ho ... index.html keen to understand more about that.

meanredspider

Rick Chasey wrote:

Surely the torque moment must be transmitted to the tyre through the wheel components: flanges, spokes, nipples, and rim spoke bed? You'd have to engineer for this moment which would inevitably lead to a heavier wheel.

If you think about it, it's six of one and half a dozen of the other. In both systems, the load (the bike/rider etc) is applied at the middle of the wheel and the braking force is generated where the wheel touches the road. Spokes support the load through tension (which is why they are thin but incredibly strong). There's no need to beef up a disc-braked wheel.

Honestly, I can hardly think of another braking system on any vehicle (including most other bicycles) that doesn't use disc brakes. Road bikes are the last bastion of rim brakes. To me, they are really Heath-Robinson. Not only that but you are wearing out your wheel! Where's (wears ) the sense in that?

supersonic

I like V brakes ;-). On some bikes...

mcj78

meanredspider wrote:

... Not only that but you are wearing out your wheel! Where's (wears ) the sense in that?

After a shitty winter of riding & not cleaning the bike as much as I should the rear rim has a distinct groove on it - can barely still see the indicator "dots" - the front is a bit better, I put that down to the rear wheel collecting much more road debris, grit & the like than the front, in addition to me being too lazy to clean it often & properly :oops:

In fact, the chain & cassette are pretty fooked too - any signs of a lightweight 20 speed internally hubbed gates belt driven disc compatible hub? 8)

rjsterry

mcj78 wrote:

meanredspider wrote:

... Not only that but you are wearing out your wheel! Where's (wears ) the sense in that?

After a shitty winter of riding & not cleaning the bike as much as I should the rear rim has a distinct groove on it - can barely still see the indicator "dots" - the front is a bit better, I put that down to the rear wheel collecting much more road debris, grit & the like than the front, in addition to me being too lazy to clean it often & properly :oops:

In fact, the chain & cassette are pretty fooked too - any signs of a lightweight 20 speed internally hubbed gates belt driven disc compatible hub? 8)

Bzzzzzzt.

MaxwellBygraves

As a fatty who spent a lot of time this summer going down insanely steep hills in Devon and wearing out wheel rims and pads at an alarming rate, whilst still struggling to actually slow down, I welcome this development.

Aidy

It's funny how some people seem to treat new technology in cycling with deep mistrust and suspicion.

Did you know that some people are still quite wary of carbon fibre?

There are even some who shun freehubs!

meanredspider

Aidy wrote:

It's funny how some people seem to treat new technology in cycling with deep mistrust and suspicion.

Did you know that some people are still quite wary of carbon fibre?

There are even some who shun freehubs!

Yup - generally it's the roadies who are slowest I think. MTB, perhaps because it's a newer discipline made up of younger people, seems quite ready (if not exactly fast) to adopt new ideas

Paul E

Aidy wrote:

It's funny how some people seem to treat new technology in cycling with deep mistrust and suspicion.

Did you know that some people are still quite wary of carbon fibre?

There are even some who shun freehubs!

Carbon Fibre was invited by witches and it casts an instant curse on whoever rides on a bike made of it and freehubs were first invented by Dracula as a way of converting people in vampires to make his evil army.

mtb-idle

meanredspider wrote:

Yup - generally it's the roadies who are slowest I think. MTB, perhaps because it's a newer discipline made up of younger people, seems quite ready (if not exactly fast) to adopt new ideas

doncha believe it, there's plenty of luddites inthe MTB world too.

Personally I love my hydraulic discs on the MTB, been riding them since 2002.

Use QR and never had an issue with wheels being pulled out of the forks. These are all the same discussions that MTB'ers had over ten years ago.

rolf_f

meanredspider wrote:

Honestly, I can hardly think of another braking system on any vehicle (including most other bicycles) that doesn't use disc brakes. Road bikes are the last bastion of rim brakes. To me, they are really Heath-Robinson. Not only that but you are wearing out your wheel! Where's (wears ) the sense in that?

Ahh, but you never seem to be able to understand the point and it isn't that hard! Discs are great for commuting bikes that get wet and mucky but offer no improvement along with increased cost, weight and complexity for weekend posh bikes. Discs simply aren't worth it for the weekend bike that doesn't get hammered day after day in crap weather. No point in them at all. Wearing out my wheel? I see no wear on my weekend bikes wheels at all! Even my Ribble which does get used for a lot of commuting shows little rim wear. It's only the Dawes that has suffered - and I have a sneaking feeling that 90% of my drivetrain wear occurs in December and January. Which means that really I'd only benefit from discs during those two months (in terms of rim wear - obviously the wet weather braking advantage always applies).

Obviously, if you are going to buy one bike - and that is your lot - and you aren't afraid of the rain, then discs make a huge amount of sense. But if you are fortunate to have a choice of bikes, on your posh bike then discs really are a duff decision. Horses for courses and all that. The Colnago is a bit of a duffer really.

I do ride an MTB with discs - but the reasons why discs are great on MTBs don't all translate to road bikes.

Stevo_666

Rolf F wrote:

Discs simply aren't worth it for the weekend bike that doesn't get hammered day after day in crap weather.

Sounds like the UK is an ideal place for road bikes with discs then. Especially for UK commuters who, erm, hammer their bikes day after day...

meanredspider

Rolf F wrote:

but offer no improvement along with increased cost, weight and complexity .

But this is the statement that I simply can't agree with. Braking IS improved - both in terms of absolute braking force but, far more importantly, in the ability to modulate the brakes to maximise the available grip. I accept that is you are afraid of getting your bike wet (even at the weekend) which, as a life-long engineer, I find silly - machines are to be used - then the vastly superior wet weather braking is going to be of limited value. I do have a choice of bikes (5 currently) and choose to use the most effective bike - the one equipped with discs. Cost and weight is VERY marginal - an extra baselayer would cover both - so, if you're at this level of worrying about weight and cost, then, again, I have to accept that discs aren't for you - I'd guess that 95% of riders aren't. Disc optimised wheels will be lighter as they are developed. Finally, complexity: I don't understand this argument - complex it what way? BB7s are an absolute doddle to fit, set up and use - arguably simpler to set up than road brakes. I was talking to a championship-level downhiller last week who was singing the praises on BB7 saying that there's really not much advantage to be had from any other brake.

mudcow007

meanredspider wrote:

Honestly, I can hardly think of another braking system on any vehicle (including most other bicycles) that doesn't use disc brakes. Road bikes are the last bastion of rim brakes. To me, they are really Heath-Robinson. Not only that but you are wearing out your wheel! Where's (wears ) the sense in that?

my hardtail has Magura hydraulic canti's - these are easy as powerful as discs but as you say they wear the rim

MTB-Idle wrote:

Use QR and never had an issue with wheels being pulled out of the forks. These are all the same discussions that MTB'ers had over ten years ago.

how come you get "bolt on" front wheels on DH bikes though?

my Kona Stinky has one...

mudcow007

double post

mcj78

mudcow007 wrote:

how come you get "bolt on" front wheels on DH bikes though?

my Kona Stinky has one...

High speed stability, improved tracking & all that jazz, plus it's obviously less prone to losing a wheel over a boulderfield should the qr come undone (unlikely though it is)

bails87

mcj78 wrote:

mudcow007 wrote:

how come you get "bolt on" front wheels on DH bikes though?

my Kona Stinky has one...

High speed stability, improved tracking & all that jazz, plus it's obviously less prone to losing a wheel over a boulderfield should the qr come undone (unlikely though it is)

They're (supposedly) stiffer, I suppose the security is a extra benefit, but a small one seeing as the wheel being pulled out of the dropouts is so unlikely as to not even register for most riders.

ddraver

Bolt through axles are purely a stiffness thing - nothing to do with QR problems. 9mmQR was invented by Campgnolo in somethign like the 1930's. Whilst it works well enough for road bikes, it is amazing how long the technology has persisted on MTB's given that there are so many advantages, other than for the weeniest of weight weenies, to bolt thru axles off road. It is something that is truely a night and day difference.

Personally (and I ve said this alot in the road section)I think that hydraulic brakes and electronic shifting are the future, In 10 years time every 105 or equivalent, GBP/EUR 1000 bike wil have both.

mudcow007

bails87 wrote:

mcj78 wrote:

mudcow007 wrote:

how come you get "bolt on" front wheels on DH bikes though?

my Kona Stinky has one...

High speed stability, improved tracking & all that jazz, plus it's obviously less prone to losing a wheel over a boulderfield should the qr come undone (unlikely though it is)

They're (supposedly) stiffer, I suppose the security is a extra benefit, but a small one seeing as the wheel being pulled out of the dropouts is so unlikely as to not even register for most riders.

ahh i gotcha!

i never knew i just thought it was to make it snazzier, its bleeding heavy though

jedster

I commute on a pompetamine with BB7s and think they are brilliant. Although they are better brakes, particularly in the wet, the main benefits for me are low maintenance and reduced rim wear. This is particularly valuable when you run dynohubs and hub gears and so can't cheapily and quickly replace wheels.

All that said, I sort of agree with this:

But if you are fortunate to have a choice of bikes, on your posh bike then discs really are a duff decision. Horses for courses and all that. The Colnago is a bit of a duffer really.

On a pure Sunday best (road) bike which you are not going to ride all that much, even less in the wet and will probably lovingly clean after most rides then caliper brakes are probably optimal. I'd not bother with discs on a carbon colnago.

meanredspider

jedster wrote:

On a pure Sunday best (road) bike which you are not going to ride all that much, even less in the wet and will probably lovingly clean after most rides then caliper brakes are probably optimal. I'd not bother with discs on a carbon colnago.

I don't understand this. But then I have a classic car that I race. I don't keep it in the garage to polish on sunny days. Life's too short and the engineers that designed it designed it to be used.

veronese68

So discs are unnecessary on an expensive bike that's just for show and not going to get ridden? I'd rather spend the money wisely on whisky and women.

meanredspider

Veronese68 wrote:

So discs are unnecessary on an expensive bike that's just for show and not going to get ridden? I'd rather spend the money wisely on whisky and women.

+1

ddraver

meanredspider wrote:

jedster wrote:

On a pure Sunday best (road) bike which you are not going to ride all that much, even less in the wet and will probably lovingly clean after most rides then caliper brakes are probably optimal. I'd not bother with discs on a carbon colnago.

I don't understand this. But then I have a classic car that I race. I don't keep it in the garage to polish on sunny days. Life's too short and the engineers that designed it designed it to be used.

+1 - I don't know about you but I look where I'm going when I ride my bikes, not down at the axles...

rolf_f

meanredspider wrote:

Rolf F wrote:

but offer no improvement along with increased cost, weight and complexity .

But this is the statement that I simply can't agree with. Braking IS improved - both in terms of absolute braking force but, far more importantly, in the ability to modulate the brakes to maximise the available grip. I accept that is you are afraid of getting your bike wet (even at the weekend) which, as a life-long engineer, I find silly - machines are to be used - then the vastly superior wet weather braking is going to be of limited value.

No, braking is not vastly improved in the dry and neither is modulation. The comment about me being afraid to get my bike wet is disingenous and unhelpful. All I have said is that it is a weekend bike. If the forecast is bad, and I still want to go out, I'll make a decision about which bike to use and if I had a disc braked road bike I would take it. However, I don't have such a bike and have enough bikes already - and discs are frankly nowhere near a good enough reason to change a bike for (as I said, the average rainy day does not cause much rim wear - it is the truly bad Dec and Jan weather when I'm not out so much anyway that does the damage). And I do find the supposed 'engineering' condemnation of caliper brakes unconvincing - they really aren't that different mechanically.

The assumption that all technological development is beneficial is wrong - witness the number of people driving unneccessarily heavy 4wd cars with huge power outputs that they never benefit from. 'Leaves on the line' is a problem partly caused by the change from conventional brakes to disc brakes.

To be honest, I think that anyone who thinks that caliper brakes is a technologically wrong solution to all is as stupid as those who don't think there is a place for disc brakes on a road bike. An engineer should understand that there are different solutions for different problems. Mind you, even when they do realise that, engineers still often get it wrong (eg Audi putting 5 speed gear boxes on Td engines with narrow torque bands and 6 speed gearboxes in the engines with wide torque bands - Vorsprung Durch Stupidity..... :roll: ).

Ideally, I would convert my tourer to discs - and it would become the worlds only disc braked touring bike with down tube shifters (which are like Di2 - a perfect shift every time (only far, far cheaper!) ).

rjsterry

Rolf F wrote:

meanredspider wrote:

Rolf F wrote:

but offer no improvement along with increased cost, weight and complexity .

But this is the statement that I simply can't agree with. Braking IS improved - both in terms of absolute braking force but, far more importantly, in the ability to modulate the brakes to maximise the available grip. I accept that is you are afraid of getting your bike wet (even at the weekend) which, as a life-long engineer, I find silly - machines are to be used - then the vastly superior wet weather braking is going to be of limited value.

No, braking is not vastly improved in the dry and neither is modulation. The comment about me being afraid to get my bike wet is disingenous and unhelpful. All I have said is that it is a weekend bike. If the forecast is bad, and I still want to go out, I'll make a decision about which bike to use and if I had a disc braked road bike I would take it. However, I don't have such a bike and have enough bikes already - and discs are frankly nowhere near a good enough reason to change a bike for (as I said, the average rainy day does not cause much rim wear - it is the truly bad Dec and Jan weather when I'm not out so much anyway that does the damage). And I do find the supposed 'engineering' condemnation of caliper brakes unconvincing - they really aren't that different mechanically.

The assumption that all technological development is beneficial is wrong - witness the number of people driving unneccessarily heavy 4wd cars with huge power outputs that they never benefit from. 'Leaves on the line' is a problem partly caused by the change from conventional brakes to disc brakes.

To be honest, I think that anyone who thinks that caliper brakes is a technologically wrong solution to all is as stupid as those who don't think there is a place for disc brakes on a road bike. An engineer should understand that there are different solutions for different problems. Mind you, even when they do realise that, engineers still often get it wrong (eg Audi putting 5 speed gear boxes on Td engines with narrow torque bands and 6 speed gearboxes in the engines with wide torque bands - Vorsprung Durch Stupidity..... :roll: ).

Ideally, I would convert my tourer to discs - and it would become the worlds only disc braked touring bike with down tube shifters (which are like Di2 - a perfect shift every time (only far, far cheaper!) ).

I'll check this with my brother - a mechanical engineer in the rail industry - but trains have had disc brakes since at least the '70s. I was under the impression that it was more to do with lineside vegetation not being cut back properly and the reduced weight of newer trains - the same reason why I can lock my back wheel much more easily than, say JZed or Sketchley. Are you really holding up block brakes that used the running surface of the wheel as a braking surface, as an example?

ddraver

What experience of disk brakes do you have Rolf, seeing as how MRS is one of the few people with a disk equipped race roadie...

meanredspider

So I'm being obviously provocative using the word "afraid" but there's a large section of the road cycling community who won't cycle in the wet on their "best" bike.

We can argue all day about force and modulation - I've ridden road bikes equipped with both systems and I'm in absolutely no doubt which is better. As I've said before in these debates, if you're built like a jump jockey, then, for sure, braking capability is low on your list of priorities and a compromise offered by rim-braking is adequate and the benefits of discs is marginal in the dry and on the broadly flat terrain of the UK. Most of us are average size and there is a clear benefit.

In that the two types of brake involve squeezing a friction material against a rotating surface, you're right, they aren't that much different. Then nor are horse & cart brakes different from F1 brakes in that respect. The rim brake though is a compromise - not wrong but a compromise: the braking surface is a compromise, the position is a compromise, the pad material is a compromise, heat dissapation is a compromise, caliper design is a compromise and so on. All of these things are fine if braking performance doesn't really matter (light rider, straight flat roads etc) and/or you are able to mitigate some of the enviromental issues (clean, dry ride). There are currently some compromises with discs - small weight disadvantage (I think disc specific wheels will more than offset this) and initial cost (it has to been seen yet whether lifetime cost vs wheel wear/damage on rim brakes offsets this) but these are both small and, I'd say, insignificant in the big picture and the world most of us occupy.

Di2 - yup, lazy luxury. We should get our water from wells, our heat from firewood and grow and prepare our own food.

bails87

MRS: seen this?

4 piston DH brakes on a Di2 road bike....? :twisted: