We will figure it out...

[weisan]

Like we always do!

This whole disc brakes... La, la, la, la, la, I told you so, thing is getting on my nerves. .:no:

Let us all go back to drinking water from the wells, eating chicken raw, walking on bare foot, running around naked....

:D

[bluesea]

Like we always do!

This whole disc brakes... La, la, la, la, la, I told you so, thing is getting on my nerves. .:no:

Let us all go back to drinking water from the wells, eating chicken raw, walking on bare foot, running around naked....

:D



go back to cane sugar from corn syrup...no wait!

[biker72]

Back to friction shifting. That new fangled index shifting will never work.

[bikinchris]

When Shimano introduced downtube index shifting at INTERBIKE, the Mavic booth people were clicking a little childs spring loaded noise maker toy made of tin and saying "if you want click shifting, just click this toy when you change gears."

[makoti]

Like we always do!

This whole disc brakes... La, la, la, la, la, I told you so, thing is getting on my nerves. .:no:

Let us all go back to drinking water from the wells, eating chicken raw, walking on bare foot, running around naked....

:D

Oh, dear sweet jesus, no. Ewww.... at least, in my neighborhood.

[johnmdesigner]

I had chicken sashimi in Osaka.
When in Rome...

[oldpotatoe]

Like we always do!

This whole disc brakes... La, la, la, la, la, I told you so, thing is getting on my nerves. .:no:

Let us all go back to drinking water from the wells, eating chicken raw, walking on bare foot, running around naked....

:D

'We'?

Vote with your $. If ya think this, along with put 'bike idea here', is good or dumb, then either use it or not.

I can say that I will never have a bike with disc brakes of any kind. BUT ultimate YMMV..your bike, your ride, do what you want. :D

[biker72]

'We'?

I can say that I will never have a bike with disc brakes of any kind.

What a revelation. I would have never guessed....SSI

[AngryScientist]

I had chicken sashimi in Osaka.
When in Rome...

but what to eat when you are in Rome?

[bluesea]

but what to eat when you are in Rome?

Raw fish air freighted from Japan, of course!

[weisan]

'We'?

Vote with your $. If ya think this...

Yes, old pal, WE...as in capital W, capital E.

We all are stuck in this little place called Earth, our common destiny is intertwined and inseparable.

If we had listened to every gripes and complaints, we would never have things like cars, microwave, cellphones... Internet. I am not saying that every human inventions are good but some things that were shoved down our throats, after the screaming and kicking stops, we became daily users benefiting from them every day.

And the customers do vote with their $, of all people, old pal, as a former bike shop owner, you should know that better than anyone else. Those who don't stop and listen, those who don't adapt and innovate... they die.

[Lewis Moon]

'We'?

Vote with your $. If ya think this, along with put 'bike idea here', is good or dumb, then either use it or not.

I can say that I will never have a bike with disc brakes of any kind. BUT ultimate YMMV..your bike, your ride, do what you want. :D

The problem is when the manu-frickin-facturers won't offer the "old stuff" any longer. I fell in love with my Raleigh Hodala a while back and wanted basically the same bike with gears. Raleigh no longer offers geared CX bikes with cantis. I emailed them to ask why this was, when the Raleigh Clement team was racing on cantis, and got back a reply that was almost dripping with "why would any sane person ride cantis" bile.
Sold the Hodala.

[Tony]

The problem is when the manu-frickin-facturers won't offer the "old stuff" any longer. I fell in love with my Raleigh Hodala a while back and wanted basically the same bike with gears. Raleigh no longer offers geared CX bikes with cantis. I emailed them to ask why this was, when the Raleigh Clement team was racing on cantis, and got back a reply that was almost dripping with "why would any sane person ride cantis" bile.
Sold the Hodala.


Like you I like my "old stuff" still riding 7700 and don't feel a need to upgrade.
However, on my cross bike I wish I had disks. Did this ride last week, (see below) a 50 mile gravel ride with a five mile descent on some very rough dirt road. It was difficult staying with the group who were riding discs. They were able to carry way more speed and brake late. My brakes were fading and my hands toast trying to slow down enough for some of the corners, wish I had discs! I've been saving up for my next rode bike. Like bianchi10 waiting for the 2nd gen Etap, not sure if I will go with discs. For ME I don't see any reason not to.
http://redkiteprayer.com/2017/02/you-call-those-foothills/

[colker]

Yes, old pal, WE...as in capital W, capital E.

We all are stuck in this little place called Earth, our common destiny is intertwined and inseparable.

If we had listened to every gripes and complaints, we would never have things like cars, microwave, cellphones... Internet. I am not saying that every human inventions are good but some things that were shoved down our throats, after the screaming and kicking stops, we became daily users benefiting from them every day.

And the customers do vote with their $, of all people, old pal, as a former bike shop owner, you should know that better than anyone else. Those who don't stop and listen, those who don't adapt and innovate... they die.

Disc brakes on road bikes is a futile idea and yes.. some of the old technology gives me a better riding experience than what´s new. Anything new that needs to kill the old ways is under my suspicion.
Btw.. cars kill cyclists, microwave food svcks and cell phones are addictive.
Conformity and acceptance of anything that´s played at power levels is not always maturity. This "we are together in this and therefore should accept what´s better for everyone" may roll in the old USSR but not everywhere.

[weisan]

I don't blame inanimate objects... I blame the operators.

It's up to us to make good of our inventions.

We are ultimately responsible.

Colker pal, you are over reaching.

[colker]

I don't blame inanimate objects... I blame the operators.

It's up to us to make good of our inventions.

We are ultimately responsible.

Colker pal, you are over reaching.

Fact is disc brake technology needs another frame and another pair of wheels. And the industry wants to turn everything obsolete when there is no need for disc brakes in a lot of riding situations. Actually, very few scenarios call for discs on road riding. And yet, you are happy to embrace the marketing of this stuff.

[weisan]

Fact is disc brake technology needs another frame and another pair of wheels. And the industry wants to turn everything obsolete when there is no need for disc brakes in a lot of riding situations. Actually, very few scenarios call for discs on road riding. And yet, you are happy to embrace the marketing of this stuff.

Just to be completely transparent, I am far from embracing the tech. I only got one bike that's disc compatible and it has the ancient BB7 mechanical. Personally, in terms of performance, i don't find it better than canti but I reserve from judgement because I know I am using old tech.

[colker]

Just to be completely transparent, I am far from embracing the tech. I only got one bike that's disc compatible and it has the ancient BB7 mechanical. Personally, in terms of performance, i don't find it better than canti but I reserve from judgement because I know I am using old tech.

See.. when sti came out, you could install it on your bike or keep using DT shifters. With discs, you throw out your bikes and wheels and buy everything new.
I see how discs make a difference on a bike w/ fat tires which is ridden in mud. I can´t see any difference on a road bike unless you are descending the alps under a storm. Ok... you can brake slightly later on the same descent when it´s sunny but it´s not better. Rim brakes stop you really well.

[weisan]

Yup, the ability to put on fat or fatter tires or swapping wheels (700cc vs 650b) is what got me to using the disc brakes I have now, not the braking power.

[Fatty]

Well people who do not like disc brakes should in fact love disc brakes.

It gives them an opportunity to score finds like this.
https://images.craigslist.org/00i0i_4iVSIul0JYD_600x450.jpg

https://chicago.craigslist.org/sox/bik/6005882248.html

[colker]

Yup, the ability to put on fat or fatter tires or swapping wheels (700cc vs 650b) is what got me to using the disc brakes I have now, not the braking power.

Steel forks.. it´s another old tech i prefer. Well.. a disc brake steel fork needs to be stiffer, stouter than a rim brake fork. Ride quality decreases because you are using technology you don´t need.

[AngryScientist]

lol. this has turned into colker's grump thread.

it's OK colker pal - no one is going to force you to buy a disc brake bike. there are plenty of rim brake compatible bikes to go around.

[Dave B]

I don't remember, did disc brakes on mountain bikes cause this much hub-bub?

[colker]

lol. this has turned into colker's grump thread.

it's OK colker pal - no one is going to force you to buy a disc brake bike. there are plenty of rim brake compatible bikes to go around.

I admit i have too much time on my hands right now and posting too much but disc brakes on road bikes make no sense. There is no NEED for that unless cheap carbon rims from China enter the equation. Even then you are trading quality shock absortion from forks and stays for who knows what.

On mtn bikes in deep humid technical woods, discs can brake unlike cantis which can´t. Needs to be said though that braking in mountain biking is entirely different from road riding: you brake all the time in technical trails.

[Mark McM]

On mtn bikes in deep humid technical woods, discs can brake unlike cantis which can´t. Needs to be said though that braking in mountain biking is entirely different from road riding: you brake all the time in technical trails.

I think a larger factor in the domination of disc brakes on MTBs is the proliferation of suspension (front and rear). Disc brakes are far more conducive to the design and operation of suspended wheels. In contrast, rim brakes are typically easier to design and operate on rigid frames and forks.

[Dave B]

I get folks are all up in arms over disc brakes. I have no idea why folks get so bent out of shape, it isn't like you HAVE to buy a bike with discs...yet. :D

But with regards to carbon wheels, china sourced or not, the complaining about braking especially when wet outside seems to lend itself to disc brakes being a pretty darn good solution. So many different companies void warranties if you don't use their pads and from my experiences carbon wheels (regardless of pads) don't stop as well as say an alloy rim.


Sooooo, if discs are the newest flavor then wont we possibly see wheels change? Lighter rims, no need for a braking surface, actually stoping in the rain?

[Kirk007]

old arguments but must disagree with the categorical argument that discs on road bikes are never beneficial.

Come ride with me all winter in Seattle, particulalry commuting down steep wet hills in pouring rain and through heavy crazy city traffic. Join me as on occasion rim brakes - of all flavors - Dura Ace, Record, Paul Center Pull - give you less than you need or lock up the wheel on unexpected quick stops and you go sliding helplessly forward. Doesn't happen often, couple times a winter - operator error perhaps but sometimes **** just happens. Now ride those same conditions with a disc brake road bike. Compare your control. Look at the bike at the end of the day - the crud on the rims, the brake pads, the etching of the rims from road crud. Then look at your disc equipped bike after the same ride and compare. Join me on a steep 8 mile descent out of the Cascades on a forest service road - mostly paved but not tour de france smooth alpine descent, but with snaking turns similar to the Alps or Dolomites. Do it in the rain with both bikes. Tell me at the bottom which was more enjoyable.

I stop just fine with my rim brake bikes 99% of the time and have no intention of ditching them. But don't type away on the internet and try and convince me that a disc braked road bike has no place in my stable of bikes until you ride my routes.

[Mark McM]

IBut with regards to carbon wheels, china sourced or not, the complaining about braking especially when wet outside seems to lend itself to disc brakes being a pretty darn good solution. So many different companies void warranties if you don't use their pads and from my experiences carbon wheels (regardless of pads) don't stop as well as say an alloy rim.

That seems like a zero sum game. The gains you make in weight and aerodynamics with carbon rims is lost with adding disc brakes. Well, not quite zero sum - the carbon rims with disc brakes costs more, with no performance gain.


Sooooo, if discs are the newest flavor then wont we possibly see wheels change? Lighter rims, no need for a braking surface, actually stoping in the rain?

History indicates that rims will not get much lighter. There have been disc-only MTB rims for quite a few years, and there are now some disc-only road rims. These are at best only a handful of grams lighter, which is completely cancelled out by the increases in weight at the hub and caliper. Disc brake wheels also typically have more spokes than rim brake wheels.

[colker]

old arguments but must disagree with the categorical argument that discs on road bikes are never beneficial.

Come ride with me all winter in Seattle, particulalry commuting down steep wet hills in pouring rain and through heavy crazy city traffic. Join me as on occasion rim brakes - of all flavors - Dura Ace, Record, Paul Center Pull - lock up the wheel on unexpected quick stops and you go sliding helplessly forward. Doesn't happen often, couple times a winter - operator error perhaps but sometimes **** just happens. Now ride those same conditions with a disc brake road bike. Compare your control. Look at the bike at the end of the day - the crud on the rims, the brake pads, the etching of the rims from road crud. Then look at your disc equipped bike after the same ride and compare. Join me on a steep 8 mile descent out of the Cascades on a forest service road - mostly paved but not tour de france smooth alpine descent, but with snaking turns similar to the Alps or Dolomites. Do it in the rain with both bikes. Tell me at the bottom which was more enjoyable.

I stop just fine with my rim brake bikes 99% of the time and have no intention of ditching them. But don't type away on the internet and try and convince me that a disc braked road bike has no place in my stable of bikes until you ride my routes.

As i said: there are a few scenarios where a disc brake road bike will make a difference on a road bike but what this turn of technology is about is not your neck of the woods(urban) riding. It´s the cheap carbon rim change that´s coming to town.

[colker]

That seems like a zero sum game. The gains you make in weight and aerodynamics with carbon rims is lost with adding disc brakes. Well, not quite zero sum - the carbon rims with disc brakes costs more, with no performance gain.




History indicates that rims will not get much lighter. There have been disc-only MTB rims for quite a few years, and there are now some disc-only road rims. These are at best only a handful of grams lighter, which is completely cancelled out by the increases in weight at the hub and caliper. Disc brake wheels also typically have more spokes than rim brake wheels.

Rotational weight wins hub weight. Otoh i believe it´s all about cheap carbon rims on cheap carbon frames w/ bad riding quality.

We will see more and more nostalgia for old steel frames w/ aluminum rims.

[Mark McM]

Rotational weight wins hub weight. Otoh i believe it´s all about cheap carbon rims on cheap carbon frames w/ bad riding quality.

The number of repeatings won't this won't change this fallacy. Mass at the periphery of the wheel does have about twice the effective inertia as mass at the center of the wheel - but inertia only matters during accelerations & decelerations.

The extra weight add a brake track on a rim is only a few dozen grams at most. But the extra mass at the center of the hub might be measured in hundreds of grams. So, in terms of total inertia, the disc brake losses to the rim brake. Which means the disc brake losses both in going uphill (extra mass) and acceleration (extra inertial).

[johnmdesigner]

but what to eat when you are in Rome?

---

[colker]

The number of repeatings won't this won't change this fallacy. Mass at the periphery of the wheel does have about twice the effective inertia as mass at the center of the wheel - but inertia only matters during accelerations & decelerations.

The extra weight add a brake track on a rim is only a few dozen grams at most. But the extra mass at the center of the hub might be measured in hundreds of grams. So, in terms of total inertia, the disc brake losses to the rim brake. Which means the disc brake losses both in going uphill (extra mass) and acceleration (extra inertial).


I am all for aluminum rims and rim brakes on steel frames but.. a carbon rim is stiffer than an aluminum rim and when used w/ discs, does not need expensive brake tracks. A stiffer rim will accelerate faster.
The mantra lighter stiffer will be used to sell a bicycle made on the cheap in China. That´s the reason behind discs on road bikes. It´s not because discs are better or safer... it´s economy of scale. It´s cheaper.

[johnmdesigner]

This doesn't warm my heart.

[ColonelJLloyd]

Disc brakes cause so much butt hurt it jumps the funny pond and lands hard in a pile of sad.

[Tandem Rider]

Weis pal;) we will not figure this out anytime soon. We're still arguing about index shifting (1984) and clipless pedals (1986), let alone carbon fiber anything. Disc brakes need to just take a number and have a seat, it's going to be a long wait. :D

[Mark McM]

I am all for aluminum rims and rim brakes on steel frames but.. a carbon rim is stiffer than an aluminum rim and when used w/ discs, does not need expensive brake tracks. A stiffer rim will accelerate faster.

Why should a wheel with a carbon rim always be stiffer than with an aluminum rim? Wheel stiffness depends on more than the rim - the number and thickness of the spokes, and the flange offset (bracing angle) often play larger roles. There are plenty of flexy carbon rim wheels, and still aluminum wheels.

Please explain how a stiffer rim accelerates faster - particularly if it is also heavier.


The mantra lighter stiffer will be used to sell a bicycle made on the cheap in China. That´s the reason behind discs on road bikes. It´s not because discs are better or safer... it´s economy of scale. It´s cheaper.

It's hard to believe a disc brake bike will be any cheaper than a rim brake bike. The disc brake bike requires more parts, higher precision parts, and more time to assemble/adjust. Currently, disc brake bikes are heavier and more expensive than rim brake bikes.

[fuzzalow]

weisan-pal, dontworryboudit.

Rim brakes will be around for a long while. So why the angst? And even if by edict all of bicycling somehow went to only all discs, so what? Won't effect my performance level either way.

The thing we ought to weigh heavily on our minds isn't rim versus disc, it is dinner tonight: steak or Italian?

[colker]

Why should a wheel with a carbon rim always be stiffer than with an aluminum rim? Wheel stiffness depends on more than the rim - the number and thickness of the spokes, and the flange offset (bracing angle) often play larger roles. There are plenty of flexy carbon rim wheels, and still aluminum wheels.

Please explain how a stiffer rim accelerates faster - particularly if it is also heavier.




It's hard to believe a disc brake bike will be any cheaper than a rim brake bike. The disc brake bike requires more parts, higher precision parts, and more time to assemble/adjust. Currently, disc brake bikes are heavier and more expensive than rim brake bikes.

A stiffer wheel accelerates faster. I agree spokes also play at making a wheel stiff but a stiff carbon rim wheel which is well tensioned w/ spokes will accelerate faster than the softer aluminum rim wheel. Carbon rims have been lighter so far than aluminium not the other way around. It´s main problem has been the brake tracks. BOras have solved that but they are expensive. Also, Boras delaminate if you apply too much braking. They are sold as racing wheels that should be not be submitted to extensive braking. Discs solve this.
Disc brake bikes are more expensive to buy right now but they will be less expensive to produce in the long run. See how cheap are frames and rims coming from China. That´s where this is all headed.

[Black Dog]

I am all for aluminum rims and rim brakes on steel frames but.. a carbon rim is stiffer than an aluminum rim and when used w/ discs, does not need expensive brake tracks. A stiffer rim will accelerate faster.
The mantra lighter stiffer will be used to sell a bicycle made on the cheap in China. That´s the reason behind discs on road bikes. It´s not because discs are better or safer... it´s economy of scale. It´s cheaper.

That is not necessarily true. Rim stiffness has little to do with acceleration of wheel.

[colker]

A stiffer wheel accelerates faster. I agree spokes also play at making a wheel stiff but a stiff carbon rim wheel which is well tensioned w/ spokes will accelerate faster than the softer aluminum rim wheel. Carbon rims have been lighter so far than aluminium not the other way around. It´s main problem has been the brake tracks. BOras have solved that but they are expensive. Also, Boras delaminate if you apply too much braking. They are sold as racing wheels that should be not be submitted to extensive braking. Discs solve this.
Disc brake bikes are more expensive to buy right now but they will be less expensive to produce in the long run. See how cheap are frames and rims coming from China. That´s where this is all headed.

the weak link in my own train of thought is: cheap carbon clinchers. Carbon is easy on tubulars. You can eliminate the brake track but you still need high standards of fabrication to secure that clincher on the rim and if this is done poorly, a hundred litigations will follow.

[colker]

That is not necessarily true. Rim stiffness has little to do with acceleration of wheel.
A stiff wheel accelerates faster. Won´t a stiff rim contribute to a stiff wheel?

[Mark McM]

I'm sorry, but this is just a bunch of gooble-de-gook.

A stiffer wheel accelerates faster. I agree spokes also play at making a wheel stiff but a stiff carbon rim wheel which is well tensioned w/ spokes will accelerate faster than the softer aluminum rim wheel.


You haven't explained the role of wheel stiffness in acceleration. And are there no other variables than just wheel stiffness?

Why do claim that aluminum rims must be "softer"? If you look at Damon Rinard's wheel stiffness test (http://www.sheldonbrown.com/rinard/wheel/data.htm), you'll see that that there are plenty wheels with deep carbon rims that are flexier than other wheels with shallow aluminum rims.

Carbon rims have been lighter so far than aluminium not the other way around. It´s main problem has been the brake tracks. BOras have solved that but they are expensive. Also, Boras delaminate if you apply too much braking. They are sold as racing wheels that should be not be submitted to extensive braking. Discs solve this.

Disc brakes may 'solve' the problem of braking with Bora wheels - but only by cancelling out the advantage of the weight savings. It is a simple fact that disc brakes add more weight to a bike than can be lost by replacing aluminum rims with carbon rims. If you believe otherwise, please add up the weights of otherwise similar disc and rim brakes and wheels, and demonstrate the difference.

Disc brake bikes are more expensive to buy right now but they will be less expensive to produce in the long run. See how cheap are frames and rims coming from China. That´s where this is all headed.

Please indicate the basis for these statements. This is wishful thinking - disc brakes require both more components, and higher precision components, than rim brakes.

30 years ago, most rim brakes were single pivot. When dual pivot brakes were introduced, they had the advantage of higher leverage - higher braking force for a given hand force - and many people liked this. But they were also heavier, more expensive, and their reduced pad clearance sometimes resulted in pad rub. The market decided they could live with the disadvantages, and adopted dual pivot brakes. But even today, dual pivots are still heavier, more expensive to make, and have reduced pad clearance - laws of physics haven't changed. Maybe the market will decide they prefer disc brakes to rim brakes. But the laws of physics will not evaporate, and they will still be heavier, and more expensive to manufacture.

[colker]

I'm sorry, but this is just a bunch of gooble-de-gook.




You haven't explained the role of wheel stiffness in acceleration. And are there no other variables than just wheel stiffness?

.

I am not a scientist so i will bring something better: experience. I have used stiffer and softer wheels. The stiffer wheel accelerates faster. I didn´t measure but i am sure i accelerated faster.
Whe you say that a lighter rim is compensated by a heavier hub you ignore that rotating mass slows you down much more than weight located at the wheel axle. It´s basic.

[Mark McM]

I am not a scientist so i will bring something better: experience. I have used stiffer and softer wheels. The stiffer wheel accelerates faster. I didn´t measure but i am sure i accelerated faster.

I think if you did measured it, you'd find that it hardly makes a difference. Also, how do you know which wheels were stiffer - did you measure this?


Whe you say that a lighter rim is compensated by a heavier hub you ignore that rotating mass slows you down much more than weight located at the wheel axle. It´s basic.

See my post on the top of this page, where I addressed the affect of rotation inertia.

Rotating mass does increase inertia - but its effect is often exaggerated. Moving mass to the periphery of a wheel doubles its effective inertia. So if you added 10 grams to a rim, it would have the same affect as adding 20 grams to the hub. But here's the rub - you can only save 20 - 30 grams of rim weight by removing the brake track, which is equivalent to subtracting 40 - 60 grams at the hub. But you have add about 150 or more grams at the hub to add a disc rotor. So the total inertia of a wheel + rotor will always be higher than for a rim brake wheel. Sorry if the math doesn't work out the way you want, but that's the reality.

[Black Dog]

I am not a scientist so i will bring something better: experience. I have used stiffer and softer wheels. The stiffer wheel accelerates faster. I didn´t measure but i am sure i accelerated faster.
Whe you say that a lighter rim is compensated by a heavier hub you ignore that rotating mass slows you down much more than weight located at the wheel axle. It´s basic.

Well, experience is not the same as data. Not at all. Data, on its own, is always unequivocal and unbiased. There are many reasons you may feel you accelerated faster, but without any actual data you can not know this, all of us are subject to our perceptions not being an accurate measure of reality. It is just part of being human. Think of optical illusions as a way to demonstrate this fact; our other sense are just as subject to misinterpretation.

As for rotational mass there is a mathematical relationship to how mass affects acceleration depending on where it is located relative to the axle. What Mark is saying, and correctly, is that the increased mass of the brakes at the axle more than offsets the decreased mass at the rim. The net effect is that disc setups reduce acceleration not increase it for a given power input.

I am not for or against discs. Lots of pros and cons. Good or bad depending on what you need.

[Seramount]

I am not a scientist...I didn't measure but i am sure i accelerated faster.

anecdotal evidence is anecdotal.

[Mark McM]

Nairo Quintana has added his name to the growing the list of pro cyclists who don't want disc brakes in the peloton:

http://www.cyclingnews.com/news/quintana-disc-brakes-are-heavier-less-aero-and-dangerous/

"Our bike brand [Canyon –ed] has disc bikes available but in my opinion we shouldn't be using disc brakes," said Quintana.

"Firstly because they don't actually brake all that well. You hear other riders' bikes in the peloton when the brake rubs up against the rotor. That's one thing. Secondly, it makes the bike less aerodynamic. Thirdly, they're much heavier."

"Lastly, there's the danger they pose in a peloton of more than 100 riders. They are good for a touring cyclist, or a person who goes out riding with two or three others and is more careful, but racing is another matter."