Doge

The bike can end up about a pound lighter. I typically beat that if I use a lighter caliper.

The discs add a few grams as do the bolts. The fork are heavier. The fluid is heavier and the brifters are heavier. The wheels are heavier as they have more spokes and beefed up hub body than the lightest rim braked wheels. It is not just calipers. There are extremely light rim brakes available.

My son's 2014 Venge is about two pounds lighter than his friend's current Venge.
I dropped 2 pounds on the tandem swapping from disc to rim brake on the front mostly because the fork was so beefy, but the discs themselves were big and heavy.
I still have a rear disc.

I don't see disc road bikes under 13.5 lbs.
A heavily raced (stiff and strong) full Di2 with steel pedal and crank spindles, cage, standard bar/stem, under 12.5 lbs.

Doge

It was interesting that the top guys last week have a similar config. The WC became very popular using his discs on a decent.
The leaders all chose differently this time. Why is likely because there was no mountain decent, or rain. When the weather is good a rimed braked bike seems preferred by the winners.
They ride both types.

surak

I wonder if Geraint Thomas losing all feeling in his hand by the end of a wet stage 4 at Romandie have anything to do with having to brake earlier, and presumably longer, than his competition? Luckily for him none of the other GC guys there were good TTers.

Doge

Clearly the top guys are getting a choice of what to use as we see the same riders with both. The ratio/throw can be adjusted in both systems although most just go stock. A rim is a 27" disc, with generally more side-to-side displacement, but both will easily lock a wheel. If I were driving a car on roads where my rotor was going to be clean and dry, I'd always pick the larger diameter. In cycling, heat is also an issue on significant descents. When the dirt, water, and long descents are not factors, makes sense to me they go for the more serviceable option.

GrainBrain

I'm surprised to see how long a wheel change takes, I have the Mavic speed release system but it doesn't seem to matter to the Pros? They still pull the whole axle out it seems. Painful to watch when they don't have a power drill but just an allen wrench.

Doge

Other things can break on bikes so it is nice to have a spare bike - to finish. But that day's race is likely over.
It does seem like the riders get to decide now, so give it a couple years and I expect different races will get different bikes and braking systems used by the lead groups. This is Risk Management - I like that they get to choose. But just another bike to have to have in the stable makes the cost go up.

MinnMan

Ineos is now going to race Pinarello's with discs....but it sounds like they will be made with QR, rather than thru axles...

So for the long standing argument about racing with discs plus thru+axles, it looks like Ineos is hoping to do it differently.

https://www.velonews.com/gear/road-g...ed-pinarellos/