The issue with your previous comment is that it is flawed:


• "Specialized S-Works Aethos Dura-Ace: 6.23kg (claimed)" an aero brick with round tubes weight specked with no pedals and no profile wheels that is marketed as a non racing bike (probably for being an aero brick), although this one could likely go under 6.8 kilos. This is what specialized says about this bike: "Don’t get us wrong, we’re all for racing. Grand Tour top steps, Classic’s Monuments—they’re in our DNA. But sometimes riding simply to ride, riding for the love of riding, is just what we need. And this is what the Aethos lives for."
• "Trek Emonda SLR9 eTap: 6.75kg (claimed)" add pedals and decent profile Wheels and you are way above 7kg
• "Cervelo R5 eTap: 6.8kg (claimed)" add pedals and profile wheels and you are way above 7kg


So basically you proved yourself wrong. And not to mention that you would be basically paying 2.5 times the price for this bikes relative to their rim bike equivalents, only those would be around 0,5 kg lighter. There is a reason grand tour winners refused to race with disc brake bikes and 2022 was the first year the tour was won on a disc brake bike.

In the interests of clarity, I have both disc and rim brake bikes and I certain like attributes of both systems. My post was obviously tongue in cheek, but was meant to highlight the fact that like it or not, the industry is going to force us to adopt certain tech, regardless of how much affection people hold for the older equipment.

Yes, you will still be able to buy rim brake wheels for a while, but you won’t be able to buy a rim brake bike from a major manufacturer.

I wonder if on ski forums people moan about parabolic skis, wishing they could still buy 220cm straight skis for convoluted reasons.

I fully agree that the industry has decided for us and that there's no way back. But your comparison with the ski industry is not right. The move to "carving" skis was a massive leap for skiers. Turning was way easier with the new skis. So not sure anybody is missing those long straight skis. Not so sure about the rear entry boots though, which I much preferred over the conventional ones.

And I am far from a luddite, actually I am in the opposite spectrum. In the case of disc brakes, this is the third transition I am experiencing. When motocross transitioned from drum brakes to disc brakes in the early 80s, there was no looking back. The advantage was so huge, that I don't remember anyone complaining. Anyone racing with drum brakes had lost even before the gate dropped. When the MTB industry did the same in the late 90s / early 00s it was almost the same. Nobody missed the cantilever or their successors, the V brakes. I don't remember anybody complaining, even though it was not as much a black and white difference as with motocross bikes. In dry races without long descents, you might still have a chance with rim brakes. And I do remember pros complaining that the initial suspensions where making them slower but they were being forced by the manufacturers to adopt them.

Road bikes are a different animal. There was no issue with rim brakes. It is just a case of the industry seeing a way to increase their profits. Yes, there are some advantages in some conditions for certain people, but overall we are being ripped by the industry. And albeit sceptical, I did try the change. I cashed 13K for a Scott Addict Supersonic (disc brake) only to find out that it was inferior in any conditions to the rim brake Scott Foil HMX it replaced. It sacrificed aeroness in exchange of an additional half a kilo for more than 2.5 times the price. Not what I would call a good deal. And this is not just Scott, it is the same with any manufacturer. Fortunately I was able to find a brand new 2019 Team Mitchelton rim brake Scott Foil HMX frame and build a similarly specked bike to the Addict for around 5K, with higher profile rims (more aero but also heavier) and 0,5 kg less.

It's not technophobe. Many of us have all kinds of technologies. In fact, I bought my second bike with disc brakes last year, my first one was in 2017 and the technology has improved indeed. I also like a good debate but many of you folks bend out of shape quite quickly.

But you are indeed a gullible bunch. Do you realize the same folks that have convinced you of riding TT bikes with disk brakes is the same bunch than convinced you to ride tubulars and 650 c wheel bikes?

What do you mean by "demonstrated" and "proven"? Please send me an unbiased paper or study and I would be happy to read it.

In real terms, it was the customer that killed the rim brake. After disc brakes were introduced on high end road bikes, many manufacturers continued dual product lines with rim and disc variants of the same bike. As disc sales increased, sometime during 2018–2019 the point of inflection or tipping point was reached and from that point on customers overwhelmingly chose to buy the disc brake version. (At the same time, orders to Shimano and SRAM for rim brake groupsets plummeted.) As an example, in a reply to a 2020 or 2021 Cyclingtips article Rob Gitelis – CEO of Factor Bikes – wrote that 93% of sales of their O2 VAM model were disc.* Clearly, when less than one in ten sales are rim, it is hardly commercially viable to keep the two product lines.

*While I have a screenshot of this, weirdly I cannot find the original post anymore.

Personally, I have still been racing on a rim brake bike the last few years (Cervelo R5), and since two years train often on a disc brake one (Caledonia). In anything involving European mountain descents with a series of tight corners, disc brakes have caused a significant change in how people descend. Whatever some people claim about the stopping efficiency of rim brakes, the reality is that with discs people can brake later, harder and with more control. In the recent GCN+ vid "Masterclass - The Art And Science Of Cornering", Nibali himself said exactly the same thing. As a result, discs have changed the way people descend and, at least with my skillset, on some descents I have not been able to stay exactly with a lined-out group, and am definitively transitioning to disc for racing this year. As for training and commuting in winter and wet conditions, between my disc brake Caledonia and my previous rim brake bike (running aluminium rims), there is no contest as to which is better and safer.

Finally, for anything integrated and aero, whether road or tri bike, discs have made a massive difference in hiding all the cables from the wind while not only maintaining but improving braking power, unlike the large majority of (PITA) custom aero rim brakes that have been developed.

The issue with disc brakes being "better" on descents is that even if they truly are better, you still need to climb before you descend in basically every race. Does the heavier bike cancel out any gains made on the descent from disc brakes?

A lot depends on parcours and terrain, rider strengths + weaknesses and their weight, tactics out on the road, so very hard to say... Nevertheless, if you have a route that includes both climb and fast/technical descent, between a combination of running numbers for effect of weight on uphills and what I have seen out on the road, I reckon that in the right hands the disk brake bike will sometimes come out in front. This is particularly the case for the latest generation of bikes seeking some optimal compromise between weight and aero (e.g. SL7, Propel). Not to be ignored is that, compared to the previous generation of light rim brake bikes, as well as having better braking, by and large the latest (integrated) disc brake bikes simply feel more solid and confidence inspiring – perhaps partly from the increased rigidity needed for having the brakes at the axle.

My first road bike experience was about 20 summers ago. I got my mom's early 80s steel bike out of the garage. It hadn't been used since when she got it in college. I put some air in the tires and went down to the local bike path. Immediately I was hooked. It was one of the summers when Lance won the Tour, and so of course, I was fascinated by the bike he was riding. My mom's bike was equipped with fat 27in clinchers that only handled maybe 70psi, narrow 38cm handlebars, and a larger cassette range in the back. Compare that to Lance with his 700x21c (guessing that tire size) tubulars at 120 psi mounted to Mavic Ksyriums, 44cm handlebars and a tight racing spec 12-23 cassette, all of which OLN and the guys at the bike shop told me were scientifically proven to be faster. No wonder I was so slow on the old bike... ;) I have seen it recently too, with the push of pressfit bottom brackets, 1x systems for road, etc. The point being that I have immense patience for people who doubt the claims made by anyone in the industry that X is faster than Y simply because the track record is poor. In fact I probably doubt most of the claims myself, at least in magnitude. Misunderstanding or misapplying the science can yield incorrect results when the delta between the two is as small as it is. What was considered the fastest bike setup by science in 2002 looks a lot different from what the fastest setup looks like today. Now don't get me wrong, there are tons of improvements that are absolutely legitimate. Carbon fiber parts, aero wheels, 11/12 gear cassettes, power meters, etc. And I do think we are getting better about understanding the limitations of lab testing vs what happens in the real world. But when these results come out, I tend to adhere to the result that is the most practical to me for at least a while or until the industry forces me to bend.

I will also say that aside from performance, there are factors that I incorporate into my decision making. Particularly, I like the sensations that come with riding. I understand that it may not be a consideration for some. But, I value not having my BB clicking every time I stand up because the pressfit BB is ever so slightly out of tolerance from the factory. I value my brakes not shrieking every time I feather them. I value not having the di2 internal wiring rattling in my handlebars every time I hit a bump. I also value being able to do my own maintenance and have a bike that makes that easy. Little things, like not having to bleed my fucking brakes just to replace a headset bearing. Yeah, I get that routing the cable there saves me 3 watts at 50kph. How much fitness do I lose from not having my bike for a week while it waits for work in the shop?

All that stated, I think my dream bike is di2 (semi wireless seems pretty cool), hydraulic disc brakes routed externally from the handlebar to the frame/fork, room for 700x30c, bsa bottom bracket. Surprisingly, it has been tough to find that combination until rather recently.

Not sure most people on here are anti disc brakes. The issues being raised are around increased costs of bikes (sure Trek will sell you a cheap domane with mechanical discs (shudder) and specialised have a cheap (still rim brake entry), but then it quickly jumps to $4-5 for a rouxbaix or tarmac.

The servicability of these bikes along with the proprietary parts (spacers) all in the name of integration and aerodynamics, providjng marginal or dubious savings of watts. Most buyers are not going to want to learn how to service a disc brake system and we are making it increasingly difficult to adjust your own fit.

There is obsolescence to consider, those special parts may be made for a limited run. When they change the shape to save you .21 watts and you can't get a replacement, is it new bike time for the price of a spacer.

Suppose that's not really about disc brakes and more about the drive for integrated and aero everything.