How many of you have converted to Disc Brake?

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Clingon
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by Clingon

Counter-intuitive results are not uncommon, especially in areas as complex as low speed aerodynamics. The greater surface area of high profile rims for example makes them faster in many high yaw scenarios due to the "sail effect". Perhaps an aerodynamically designed rotor could achieve something similar? I have no doubt that there are engineers at major manufacturers who are already turning their minds towards this problem.

In any case, I think the main takeaway from the above tests is not the crosswind performance which, as you say, is unsurprising. The more notable result is the very small, even non-existent, effect at more relevant low yaw angles. For most users, most of the time, disc brake it appears will have no meaningful effect upon aerodynamic performance.

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Calnago
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by Calnago

Yes, Zipp used to claim how their Subzero disc wheels (not brakes) actually had a lifting forward thrust effect. That was before frame manufactures started narrowing things up in the rear, to the point that the damn things hardly fit into any frames. So then they came out with their SuperZero disc that is available today still I believe (I have one). It however, is not the subzero shape but pretty much flat. So they were then faced with a marketing quandary of how to explain the change, since who would want a flat disc if the Subzero had this wonderful forward lifting thrust effect. Ha... they simply said... meh... there's not really any difference to speak of and went forward with the newer flat design which actually fits into the rear of tt bikes. And life went on.... lol
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MichaelB
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by MichaelB

Have been on a road disc bike in some format since about 2010. Started with added a CX fork to my roadie and never looked back.

Don't NEED it, but the discs just work better all round, especially in the wet.
Don't live in the alps, but have a good range of hills with some nice descents though.

Delorre
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by Delorre

Calnago wrote:Do you really need a test to tell you that in crosswinds a greater surface area will catch more wind than a smaller surface area? Sometimes, a test isn't even needed if some very basic concepts are understood.


Exact, my Endurace is more affected by crosswinds compared to my Scott, altough shallow alloy rims on the Canyon vs 35 deep Bora's on the Scott. Nothing to worry about, but I notived it right away.

Keeponspinning
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by Keeponspinning

I'm relatively new to road riding, having come back to it after c20 yrs away and my guess is that lots of new riders will instinctively go for discs over rims.

When I bought my bike last year, it seemed an absolute no brainer to buy a disc bike. Several reasons, the first of which I appreciate is anathema to this board: I wasn't worried about weight. I was overweight and new that a few grams saved here or there was nothing compared to the need for me to lose weight.

Also, being heavier I wanted some reassurance the bike would stop under me.

After a year in the saddle and having lost considerable weight I'm obviously looking at n+1. I'm only looking at disc versions, most likely the Cervelo R3, maybe the Canyon Endurace or dream bikes of Colnago C60 or Parlee.

I know they're not quite as svelte as their rim braked siblings, but I love the confidence of riding the bike. Genuinely, I'm surprised by comments on here that people are concerned going out in the rain on their rim bikes. Literally never occurred to me. Only reason for not going out in rain IMO is to not get wet. I've total certainty about the bike.

TL;DR newbies are far more likely to go for discs, especially as top end manufacturers are making (and selling) some stunners.

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Miller
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by Miller

I've been running a disc-braked bike since 2013, there's a build thread on here about it. It's based on a generic carbon CX frame with a Campag drivetrain and TRP hy/dr brake calipers. It's been a superb bike for general wet weather duties, and this year a bit of gravel riding too, but I don't consider it as 'fast' as my rim braked summer bike even though I've clocked enough segment bests on it. That would be down to being generally heavier at around 8.5kg and always running tyres of 28mm and up.

The medium term aim for me is a summer bike ticking all the boxes: Campag hydraulic discs, EPS, tubeless. Could have that now with another groupset I guess but I'm content to wait.

When discs come back into pro racing it will certainly be an interesting moment when the first race is won aboard a disc-braked bike.

Bridgeman
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by Bridgeman

Calnago wrote:Do you really need a test to tell you that in crosswinds a greater surface area will catch more wind than a smaller surface area? Sometimes, a test isn't even needed if some very basic concepts are understood.


I absolutely agree with this. There are numerous conditions dealing with heavy side winds, including fast descents with sudden open areas that cause severe abrupt side loads that are more than a hand full that we encounter here frequently. Bad things have happened to those who have planned for this by riding shallow wheels. It's way worse for those that didn't and got caught out, I can tell you!

MoPho
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by MoPho

Delorre wrote:
Exact, my Endurace is more affected by crosswinds compared to my Scott, altough shallow alloy rims on the Canyon vs 35 deep Bora's on the Scott. Nothing to worry about, but I notived it right away.



You must be really sensitive, I can't tell much difference between my rim or disc bike in cross winds nor the difference in weight of the brake levers as you say and both bikes are Giant TCR's with deep rims (albeit different depths)
Maybe there is, but unless I was to ride the bikes back to back in the same conditions and with the same wheels I could not make a valid assessment.


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mpulsiv
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by mpulsiv

MoPho wrote:
Delorre wrote:
Exact, my Endurace is more affected by crosswinds compared to my Scott, altough shallow alloy rims on the Canyon vs 35 deep Bora's on the Scott. Nothing to worry about, but I notived it right away.



You must be really sensitive, I can't tell much difference between my rim or disc bike in cross winds nor the difference in weight of the brake levers as you say and both bikes are Giant TCR's with deep rims (albeit different depths)
Maybe there is, but unless I was to ride the bikes back to back in the same conditions and with the same wheels I could not make a valid assessment.


.


Yes, some rides are more sensitive than others. I have mentioned this numerous times. We can sense minor changes in bike fit, minor difference with tires, minor difference with vertical compliance, minor changes in weather, etc. In contrast some riders are like wood, can't feel anything and it's not their fault.
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MoPho
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by MoPho

mpulsiv wrote:
Yes, some rides are more sensitive than others. I have mentioned this numerous times. We can sense minor changes in bike fit, minor difference with tires, minor difference with vertical compliance, minor changes in weather, etc. In contrast some riders are like wood, can't feel anything and it's not their fault.



I wouldn't call that a fault.

And again, unless you are testing these things back to back, with the same components and in the same conditions, there are too many variables to draw solid conclusions.

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mpulsiv
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by mpulsiv

MoPho wrote:
mpulsiv wrote:
Yes, some rides are more sensitive than others. I have mentioned this numerous times. We can sense minor changes in bike fit, minor difference with tires, minor difference with vertical compliance, minor changes in weather, etc. In contrast some riders are like wood, can't feel anything and it's not their fault.



I wouldn't call that a fault.

And again, unless you are testing these things back to back, with the same components and in the same conditions, there are too many variables to draw solid conclusions.


What I mean by "not your fault" is your body, your nervous system, your reactions, your overall sensitivity, your pain threshold, etc. Whatever triggers your brain...
Racing is a three-dimensional high-speed chess game, involving hundreds of pieces on the board.

:arrow: CBA = Chronic Bike Addiction
:arrow: OCD = Obsessive Cycling Disorder

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Miller
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by Miller

The main thing is that these differences are absolutely not imaginary. In no way.

Stueys
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by Stueys

I've not seen any data to back this up so it's a pure view point, but I'd be very surprised if a rotor positioned on the hub really made much difference in a cross wind. I'm struggling to see that something on the hub is going to generate much steering torque, in the same way that a deep rim could.

MoPho
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by MoPho

mpulsiv wrote:What I mean by "not your fault" is your body, your nervous system, your reactions, your overall sensitivity, your pain threshold, etc. Whatever triggers your brain...



Right, but you made it sound as if not being overly sensitive to such minutiae is a bad thing


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Delorre
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by Delorre

MoPho wrote:
Delorre wrote:
Exact, my Endurace is more affected by crosswinds compared to my Scott, altough shallow alloy rims on the Canyon vs 35 deep Bora's on the Scott. Nothing to worry about, but I notived it right away.



You must be really sensitive, I can't tell much difference between my rim or disc bike in cross winds nor the difference in weight of the brake levers as you say and both bikes are Giant TCR's with deep rims (albeit different depths)
Maybe there is, but unless I was to ride the bikes back to back in the same conditions and with the same wheels I could not make a valid assessment.
.


Yep, I am! Even very small changes in riding position cause some strange feeling the first hour, sometimes causing back pain etc. And by small, I mean a few mm. As others have said, some of us are very sensitive, others, like my father, don't feel any difference between 2 bikes that in reality behave very differently (weight, geometry etc) Regarding shifter weight, do this simple test : put both bikes upright, wheels in straight line, than lean both bikes slightly to one side. The disc shifter willl cause the steerer to turn the handlebar a lot faster and with less bike angles as the non disc bike! Of course, both bikes with tyres at +/- th same pressure... and assuming both headsets spin smoothly. Ran the disc bike on the rollers today, and :shock: what a concentration it takes to stay on them, again (I suppose) the weight of the shifters that tend to amplify every small imput on the handlebar. On the road, the Canyon is a lot more stable than the Scott, on the rollers, it's the other way around

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