Disc Vs Rim Braking System

[MichaelB]

....
One of the most innovative F1 engineers named Colin Chapman had a saying "just add lightness". His holy grail was reducing the number of components, and making single components do multiple tasks. I'm pretty sure he wouldn't approve of the changes.

So please explain to me how that applies to rim vs hyd discs (apart from the fact that a hyd disc brake system is slightly heavier than a rim brake system) ?

If you look at his quote, the lightness comes from simplicity and part count reduction. Rim calipers whilst lighter, probably (haven't checked) would have a higher parts count than a hyd caliper .

It would be interesting to see what the cost of manufacture of each system is (not the RRP).



And finally (AT) Comedian - with all due respect, and I'm happy to be proved wrong, but there are many assertions (and some completely wrong facts) from you re why Disc brakes are no good/wronfg/etc when it appears that your actual use & experience with them (short or long term) is none to minimal.

[Comedian]

....
One of the most innovative F1 engineers named Colin Chapman had a saying "just add lightness". His holy grail was reducing the number of components, and making single components do multiple tasks. I'm pretty sure he wouldn't approve of the changes.

So please explain to me how that applies to rim vs hyd discs (apart from the fact that a hyd disc brake system is slightly heavier than a rim brake system) ?

If you look at his quote, the lightness comes from simplicity and part count reduction. Rim calipers whilst lighter, probably (haven't checked) would have a higher parts count than a hyd caliper .

It would be interesting to see what the cost of manufacture of each system is (not the RRP).

In a disc brake system you have to add a rotor and strengthen the hub to carry it, You have to add mounts to the fork and rear triangle. Due to the physics of the change in braking forces the fork, triangle, and wheels have to be strengthened to accomodate them.

With rim brakes, they use the wheel which is already there and which has to be strong to accomodate the force of the clinchers. Also, as the load are in a better place it enables lightening of several components. He'd like that.

And finally (AT) Comedian - with all due respect, and I'm happy to be proved wrong, but there are many assertions (and some completely wrong facts) from you re why Disc brakes are no good/wronfg/etc when it appears that your actual use & experience with them (short or long term) is none to minimal.

Yes, you're right. I've had only two disc brake bikes. I've got one hydraulic rim brake bike. Some troubles I've had with those bikes.

- Alfine caliper leaking. - resulting in big noise and no stopping. Replace whole unit. 3x replacement pad sets in 10k
- Avid brakes on mountain bike. Dragging, squealing, ticking. Told no way of fixing - just replace both brake systems completely (2.5k covered). This is as yet unresolved.
- Hydraulic rim brake - caliper leaking. Warranty replacement of the entire system with three weeks off road.

I've done about 60k on the road bikes which is probably 6x more than the three bikes above. In that time I've replaced maybe 3 or 4 sets of pads? No cables. No parts, no callipers. Yes, you're right I haven't used discs much. But can you see why I'm not rushing to the technology? I haven't got time for that stuff!

[koshari]

if you read my post, my 5600 brakes/shifter combo are not good, in fact scared I would not stop kind of "not good"

my avid sd7 lever / standard tektro mini v-brakes where miles better in the wet.

5600 had koolstop salmon pads both front and back. v-brake setup had the koolstop tectonic pads (2/3 black, 1/3 salmon) front and whatever came with bike rear pads.

interesting observations

i have a few similar setups,
- st-r700 set of shifters pulling tektro rx40 calipers
- st-2300 shifters pulling tektro mini Vs
- st-r500 onto rx-100 clipers.
- st-5600s onto exage 300 calipers.
i read a lot of critisism aimed at tektro however from my experience the first 2 setups do very well and on a par with the 3rd setup onto rx100 , no probs pulling up even with a little bit of moisture, the 4th setup with the single pivots is definitely inferior but "gets the job done". maybe one day i will change these calipers out but its a vintage bike and i like keeping most of the groupo together,

for the record i only have one bike with discs, a 26" hardtail with mech discs, and yes they pull up very in all conditions well but are bloody noisy as they squeal.

personally i cant think of any compelling reasons to migrate to road discs atm, iam considering building up a tourer sometime in the future where i may consider discs, but at the moment my Giant CRX with drops (- st-2300 shifters pulling tektro mini Vs) still fills that role perfectly. I would be more inclined to swap the st-2300 shifters with shifters with paddle upshifting rather than the little thumb lever. side entry cabling doesn't bother me at all.

[silentC]

you see why I'm not rushing to the technology

I'll just reiterate my prediction that if your next roadie is not disc braked, the one after certainly will be

[koshari]

you see why I'm not rushing to the technology

I'll just reiterate my prediction that if your next roadie is not disc braked, the one after certainly will be

My first roadee was sourced in 1989 and my second in 2015 at this rate the one after my next will be in.... 2065!! By then I would prolly be looking at regenerative braking ( will need it if iam still riding in my 90s) , KERS anyone? http://www.instructables.com/id/Regener ... le-Safety/

[silentC]

I'm much the same, first 'real' roadie in 1993, second in 2015, but I am already on the disc bandwagon

But seriously, I reckon within one or two iterations, disc brakes will be so common on road bikes that you will have to go out of your way to get one with rim brakes. They will still be available for those who want them but they will be a sideline, and eventually become quite rare. New entrants will not even spare them a thought.

Let's come back in 10 years and prove me wrong!

[Nobody]

....
One of the most innovative F1 engineers named Colin Chapman had a saying "just add lightness". His holy grail was reducing the number of components, and making single components do multiple tasks. I'm pretty sure he wouldn't approve of the changes.

So please explain to me how that applies to rim vs hyd discs (apart from the fact that a hyd disc brake system is slightly heavier than a rim brake system) ?...

In a disc brake system you have to add a rotor and strengthen the hub to carry it, You have to add mounts to the fork and rear triangle. Due to the physics of the change in braking forces the fork, triangle, and wheels have to be strengthened to accomodate them.

With rim brakes, they use the wheel which is already there and which has to be strong to accomodate the force of the clinchers. Also, as the load are in a better place it enables lightening of several components. He'd like that.

Hard to argue against this for dry weather riding. I may consider rim brakes for my next road bike since I only ride it in dry weather. That is if I can get enough braking power actuated from the hoods. Maybe hydro rim brakes would help with that.

But most people who don't live in mainly dry climates like Brisbane or Perth and don't race aren't likely to miss the extra lightness and discs may just save them one day from a crash in wet conditions.

The next innovation that most who ride in the wet may benefit from (if only once or twice) is a good and light electronic ABS system for bicycles. I know my wet weather riding can feel pretty slippery and precarious at times, even though I'm on 2" Marathons at lowish pressure (35/42psi).

I'm aware of its value since I've locked up a front wheel on a motorbike and went down at a set of lights about 25 year ago (one of many crashes). Probably wouldn't buy another motorbike. But if I did, I'd want ABS.

[koshari]

to a degree your choices are a reflection of what the manufacturers are offering, given discs require different frames /wheelsets its hard to imagine they will offer both indefinitely.

I aware of its value since I've locked up a front wheel on a motorbike and went down at a set of lights

realistically you dont even have to brake to lose the front, i had the front wash out last week on a BMX ( didn't even have front brakes) simply due to a collection of little pebbles sitting at the base of the 2nd berm turn, bit of a ballbearing effect and the front was lost before i even realised.

also lost the front on my KDX a few years back from a patch of oil on a sealed section

[P!N20]

But seriously, I reckon within one or two iterations, disc brakes will be so common on road bikes that you will have to go out of your way to get one with rim brakes.

Anticipating 'vintage disc brakes' thread in the retro sub-forum.

[Bendo]

I'm much the same, first 'real' roadie in 1993, second in 2015, but I am already on the disc bandwagon

But seriously, I reckon within one or two iterations, disc brakes will be so common on road bikes that you will have to go out of your way to get one with rim brakes. They will still be available for those who want them but they will be a sideline, and eventually become quite rare. New entrants will not even spare them a thought.

Let's come back in 10 years and prove me wrong!

Well I'm using rim brake tech that is already 40+ years old (Mafac Raids). Personally I'm not looking to innovation to improve my riding experience. AFAIC it's optimal already. viewtopic.php?f=23&t=530&start=2700#p1388321

I am, on the other hand, looking to innovation to help us solve our energy problems and save the planet! On that score I think all of us, rim and disc users, are doing our bit. Some of us are even generating electricity while we ride! But that's another trhead... b

[warthog1]

I'm much the same, first 'real' roadie in 1993, second in 2015, but I am already on the disc bandwagon

But seriously, I reckon within one or two iterations, disc brakes will be so common on road bikes that you will have to go out of your way to get one with rim brakes. They will still be available for those who want them but they will be a sideline, and eventually become quite rare. New entrants will not even spare them a thought.

Let's come back in 10 years and prove me wrong!

I agree, but not because people really want or need them, at least in racing and sportive circles.
The reality is the industry sees this as the latest performance "upgrade" and marketing push.
They will win out.

[silentC]

I think there will be an increasing number of (mostly amateur) cyclists wanting them - they may not need them, it's difficult to define it as a need.

I said to the LBS owner just before I bought my current bike "have you ever been tearing down a hill and wished you had disc brakes?" The answer was no, because rim brakes are good enough. A few weeks later, I saw the prices of the 2015 bikes after the 2016 line was released, and probably due to the lack of interest in discs at the time, I got a price that was too good to refuse, so I ended up with discs anyway. I certainly never set out to buy a bike with them.

A couple of months ago, the same LBS guy told me that his next bike would have disc brakes, because when he did the 'round the block' ride from Jindabyne last year, there were a couple of descents where he felt his rim brakes were only just cutting it. I'm not sure how real or perceived that is but he has changed his tune from a couple of years ago.

But yes I suppose it will be foist upon us. Some might see it as a backwards step right now but I am convinced that at some point in the not too distant future, hardly anyone will understand what all the fuss was about.

[MichaelB]

...In a disc brake system you have to add a rotor and strengthen the hub to carry it, You have to add mounts to the fork and rear triangle. Due to the physics of the change in braking forces the fork, triangle, and wheels have to be strengthened to accomodate them.

With rim brakes, they use the wheel which is already there and which has to be strong to accomodate the force of the clinchers. Also, as the load are in a better place it enables lightening of several components. He'd like that.

Yes, you're right. I've had only two disc brake bikes. I've got one hydraulic rim brake bike. Some troubles I've had with those bikes.

... [deleted for brevity]

So If I say that I've had 3 different disk braked bikes over the last 8 years & ~ 55,000km (on discs) and had none of those troubles, yet had issues with a caliper brake, that makes it caliper brakes are inferior ?

3 sets of pads in 10k km - and ?

I wore through a set of Saint MTB pads on the front of my roadie after 4,500km and less than 6 months. Mind you that included a few alpine steep descents like the steep side of Passo Fedaia, Passo Pordoi, Umbrail Pass, Monticello, Tre Cime (part of) in the wet, etc (550km in total) with the rest in alpine Adelaide. Don't know how many sets of rim brake pads I would have gone through in the same time ?

[sigh] This whole disc brake vs rim brake is now worse and sillier than the MHL thread Anchors away here too.

Oh, and with some other hydraulic caliper systems, individual parts and seals can be purchased - SRAM, Hope etc.

[g-boaf]

- Hydraulic rim brake - caliper leaking. Warranty replacement of the entire system with three weeks off road.

Which brand was that? I've got Magura RT8 TT brakes and those are great, they feel enormously powerful. Once I got them set up correctly they are great. They've also been very dependable, though the rear brakes need constant cleaning as they collect all manner of dirt and grime (mounted near the bottom bracket).

Mark Cavendish mentioned using something similar on one of his road bikes and reckoned the stopping performance was incredible, I know what he means.

[Comedian]

[sigh] This whole disc brake vs rim brake is now worse and sillier than the MHL thread Anchors away here too.

Oh, and with some other hydraulic caliper systems, individual parts and seals can be purchased - SRAM, Hope etc.

But not shimano which is the vast majority of our market?

Anyway I don't know why you've not had problems but I'm happy. What's wrong with me being happy that good rim brakes have exceeded my expectations for performance and durability? Isn't that awesome too? I fully expect that some people will love their disc brake bikes. I fully expect that some won't though. You and Duck seem to think it's all going to be beer and skittles..

Don't worry though. You will prevail. In case you haven't noticed everyone in the bike industry is salivating at the thought of a technical shift so great that it will result in everyone having to walk away from all their current roadbikes, and components. It's that big.

I fully expect that once the industry thinks they've sold everyone a disc braked bike that they will "revive" rim brakes as a performance niche and try and sell into that too.

[Comedian]

- Hydraulic rim brake - caliper leaking. Warranty replacement of the entire system with three weeks off road.

Which brand was that? I've got Magura RT8 TT brakes and those are great, they feel enormously powerful. Once I got them set up correctly they are great. They've also been very dependable, though the rear brakes need constant cleaning as they collect all manner of dirt and grime (mounted near the bottom bracket).

Mark Cavendish mentioned using something similar on one of his road bikes and reckoned the stopping performance was incredible, I know what he means.

Magura hydraulic rim brakes. Yep, great when working.

However now they have been bleed with the adjustment screw in by the workshop so now they don't bite until nearly on the bars. I suppose I'll have to take them back to the bike shop or investigate buying a bleed kit and fluid and trying to make them bite earlier. I wonder if any of the disc/hydro lovers will pop around and provide the gear and parts and show me how to do it? Or take it back to the shop and leave it with them for days and pay the $100 labour?

Everyone tells me these things are so simple and trouble free? I could have fixed this with normal brakes with one allan key

[Duck!]

Rim calipers whilst lighter, probably (haven't checked) would have a higher parts count than a hyd caliper .

By my rough count, a hydro disc caliper contains 14 individual parts, vs around 40 in a rim caliper.

[g-boaf]

- Hydraulic rim brake - caliper leaking. Warranty replacement of the entire system with three weeks off road.

Which brand was that? I've got Magura RT8 TT brakes and those are great, they feel enormously powerful. Once I got them set up correctly they are great. They've also been very dependable, though the rear brakes need constant cleaning as they collect all manner of dirt and grime (mounted near the bottom bracket).

Mark Cavendish mentioned using something similar on one of his road bikes and reckoned the stopping performance was incredible, I know what he means.

Magura hydraulic rim brakes. Yep, great when working.

However now they have been bleed with the adjustment screw in by the workshop so now they don't bite until nearly on the bars. I suppose I'll have to take them back to the bike shop or investigate buying a bleed kit and fluid and trying to make them bite earlier. I wonder if any of the disc/hydro lovers will pop around and provide the gear and parts and show me how to do it? Or take it back to the shop and leave it with them for days and pay the $100 labour?

Everyone tells me these things are so simple and trouble free? I could have fixed this with normal brakes with one allan key

I don't bleed my own ones either, rather I visit the distributor who is pretty good. I know you can buy the kit to bleed them, but yes, they are tricky. At least mine are trouble free, it did take a while to get them feeling the right way with more immediate effect. That was done by bleeding them and changing the pads to ones that were thicker and using the allen key adjustment in the front of the levers.

I've also got another set of them thanks to a shipping/procurement stuff up, so those are spares.

[MichaelB]

Rim calipers whilst lighter, probably (haven't checked) would have a higher parts count than a hyd caliper .

By my rough count, a hydro disc caliper contains 14 individual parts, vs around 40 in a rim caliper.

Cheers for that.

Wonder what the actual manufacturing cost of each one would be ?

[Comedian]

Rim calipers whilst lighter, probably (haven't checked) would have a higher parts count than a hyd caliper .

By my rough count, a hydro disc caliper contains 14 individual parts, vs around 40 in a rim caliper.

Cheers for that.

Wonder what the actual manufacturing cost of each one would be ?

I'm not sure, but it appears if you want performance your best bet is rim brakes.

Now that the number of disc-equipped race bikes on the market is growing, it’s clear that there is significant weight penalty attached to the new braking system. In any other setting, such concerns would be relatively easy to dismiss, but for those racers trying to maximise the competitive edge of their equipment at a reasonable price, rim brakes cannot be trumped.

https://cyclingtips.com/2017/01/cannond ... on-review/

[Duck!]

As mentioned in that other thread, given Marcel Kittel recently won a couple of sprints on a disc-braked bike, clearly the assumed negative weight & aero effects aren't that significant.

[RonK]

As mentioned in that other thread, given Marcel Kittel recently won a couple of sprints on a disc-braked bike, clearly the assumed negative weight & aero effects aren't that significant.

I've noticed that Marcel Killel also won a couple of sprints on a rim-braked bike, clearly the assumed inferior braking performance is not that significant.

[RonK]

I'm not sure, but it appears if you want performance your best bet is rim brakes.

Now that the number of disc-equipped race bikes on the market is growing, it’s clear that there is significant weight penalty attached to the new braking system. In any other setting, such concerns would be relatively easy to dismiss, but for those racers trying to maximise the competitive edge of their equipment at a reasonable price, rim brakes cannot be trumped.

https://cyclingtips.com/2017/01/cannond ... on-review/

Cycling Tips said that?

Heretics!

Cycling Tips should be burned at the stake.

[trainspotter]

Rim calipers whilst lighter, probably (haven't checked) would have a higher parts count than a hyd caliper .

By my rough count, a hydro disc caliper contains 14 individual parts, vs around 40 in a rim caliper.

I've just disassembled my Super Record calipers and found these to have 38 parts for the front dual pivot, and 33 for the rear single pivot caliper, so your rough count is pretty accurate.
Can you put them back together for me now?

[MichaelB]

Rim calipers whilst lighter, probably (haven't checked) would have a higher parts count than a hyd caliper .

By my rough count, a hydro disc caliper contains 14 individual parts, vs around 40 in a rim caliper.

I've just disassembled my Super Record calipers and found these to have 38 parts for the front dual pivot, and 33 for the rear single pivot caliper, so your rough count is pretty accurate.
Can you put them back together for me now?

If they were disc calipers, yes (done it many times in my repurposing Avid Trail calipers to run Mineral oil ....). Otherwise you are SOOL.