Rim brake carbon 50mm-60mm STIFF wheelset?

[RedRacer]

Shopping for modern high-end rim brake carbon clinchers in 2021 is a bit depressing - most of the latest and greatest offerings are disc only - looking at you Roval, Bontrager, HED and Zipp.

Basic info: S Works Tarmac, 25C tires, rolling terrain (rarely over 10%), all-around wheelset for riding and racing, 84kg, ~1500W sprint, love to corner fast.

Currently on 2018 Rovals which I like but my goal is to get a stiffer rear wheel assuembly for less brake rub and gaining some aero advantage would be a nice bonus.

2018 Roval CLX50 Rapid
1375g / 20.7mm internal, 29.4mm external
Spoke count Front/Rear: 16/21 (rear Radial/Two-cross 2:1)
Spoke type DT Swiss Aerolite T-head

What can I buy to acheive my goals? Here is what I found.

Bora WTO 60
1547g / 19mm internal, 26.5mm external
Spoke count Front/Rear: 18/21 (rear G3 pattern)

*Reportedly stiff but the low spoke count worries me. Nice bearings.

ZIPP NSW 404 (58mm)
1592g / 20mm internal, 26.4mm external
Spoke count Front/Rear: 18/24

*I have read that Zipps aren't stiff but 58mm + 24 spokes should be good? Five year old model/technology.

ENVE SES 5.6
1593g / 20mm internal, 29mm external
Spoke count Front/Rear: 20/24

*The internal spoke nipples are a real turn-off. Rims are heavy (494g/517g) but maybe not heavier than other similar rims? Nice that ENVE publishes the weights!

Have I missed any good options? DT Swiss and Swiss Side are only 21 spoke rear, same as I have now. Frankly the Campagnolo, Zipp and Enve options don't seem like performance upgrade from what I have (~200g weight penalty) unless they are much stiffer.

The last option could be custom built wheels but I've had two bad experiences with high-end custom carbon wheels so this option doesn't excite me.

[Nickldn]

I have this issue with my 55mm deep wheels, but can't detect flex in the actual rear wheel.

Do you think the brake rub is coming from un-stiff wheels? Nothing to do with skewers, or compliance in chainstays?

[kgibbo1868]

Shimano C60 would be worth a look.


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[RedRacer]

I have this issue with my 55mm deep wheels, but can't detect flex in the actual rear wheel.

Do you think the brake rub is coming from un-stiff wheels? Nothing to do with skewers, or compliance in chainstays?

Lack of rear wheel lateral stiffness is my best guess. I had the same Rovals on an SW SL5 and SL6 and got the same brake rub Skewers are DA 9100.

[Nickldn]

I have this issue with my 55mm deep wheels, but can't detect flex in the actual rear wheel.

Do you think the brake rub is coming from un-stiff wheels? Nothing to do with skewers, or compliance in chainstays?

Lack of rear wheel lateral stiffness is my best guess. I had the same Rovals on an SW SL5 and SL6 and got the same brake rub Skewers are DA 9100.

Your skewers are good. I use little titanium ones and put up with the brake rub, so spread the caliper arms a bit more.

[Mr.Gib]

Brake rub may not be caused by a flexible wheel. In fact there is a good argument that a more flexible wheel will result in less brake rub. If the wheel is flexible, the bottom half (the half in contact with the ground) will bend, while the top half will stay vertical. A stiffer wheel may hold its vertical position in total and force the rear end of the frame to move laterally bring the rim in contact with the pads. I had a frame that was a bit too flexible for me. Brake rub was worse with deeper wheels. This is a problem with larger, powerful riders. Two solutions: open up the rear caliper and count on the front for stopping (what you should do anyway), or find a stiffer frame. PIA I know.

[RedRacer]

Brake rub may not be caused by a flexible wheel. In fact there is a good argument that a more flexible wheel will result in less brake rub. If the wheel is flexible, the bottom half (the half in contact with the ground) will bend, while the top half will stay vertical. A stiffer wheel may hold its vertical position in total and force the rear end of the frame to move laterally bring the rim in contact with the pads. I had a frame that was a bit too flexible for me. Brake rub was worse with deeper wheels. This is a problem with larger, powerful riders. Two solutions: open up the rear caliper and count on the front for stopping (what you should do anyway), or find a stiffer frame. PIA I know.

Mr.Gib

Your Factor O2 VAM Review was one of my favourite WW threads so the issue of frame stiffness is fresh in my mind. I should also mention that I don't think having a less-that-ultra-rigid rear wheel is the reason I haven't been signed by a pro team but I really dislike the sound of brakes rubbing and I love a super solid feel with granular feedback, ride quality be damned. Should I mention that I run my 25C tires at 100psi+

To your point about stiff wheels and brake rub, my understanding is that from most to least brake rub it goes like this - Ultra stiff rim with flimsy spokes (most rub) > decently balanced rim+spoke stiffness combo > Ultra stiff rim with excellent spoke bracing (hypothetically 60mm carbon with 32 x 14g spokes) for the lowest amount of rubbing.

As good as most of todays carbon wheelsets are I believe a comment that was posted in another thread suggesting that 'sexy sells', meamning that light weight wheelset with radial or innovative spoke lacing attracts buyers, but sometimes what looks lame on paper might work better on the road, like a slightly heavier rim with 24 thicker spokes. I can also see how a 175cm 65kg rider with a 1000w sprint wouldn't put nearly the same level of stress/torque/load/whatever into the wheel(s) as a 188cm 84kg rider with a 1500w sprint.

This wheel search would be easy for a disc set-up but I think us rim brakers are getting left behind.

[Maddie]

This wheel search would be easy for a disc set-up but I think us rim brakers are getting left behind.

Still plenty of choices out there. DT Swiss, Campagnolo and Zipp for instance make excellent aero rim brake wheels. Or talk to a wheel builder and go custom. 28 spokes or even 32 at the rear could be an option for you.

[TobinHatesYou]

Bontrager XXX 4 (47mm) and 6 (60mm) should still be available.

[calleking]

I read on several sites that Winspace Hypers are extremely stiff laterally. You should be able to run the brake pads very close to the rim with no rubbing.
I have a set incoming but will not be able to try them until spring here in Scandinavia. I was previously on ENVE SES 4.5 with DTS240s/Sapim CX and the rear wheel rubbed every now and then on climbs and I was constantly releasing the calipers before climbs which was quite annoying. I think the rim vs hub/spike combination was an issue with the rim being very stiff.

[Mr.Gib]

Brake rub may not be caused by a flexible wheel. In fact there is a good argument that a more flexible wheel will result in less brake rub. If the wheel is flexible, the bottom half (the half in contact with the ground) will bend, while the top half will stay vertical. A stiffer wheel may hold its vertical position in total and force the rear end of the frame to move laterally bring the rim in contact with the pads. I had a frame that was a bit too flexible for me. Brake rub was worse with deeper wheels. This is a problem with larger, powerful riders. Two solutions: open up the rear caliper and count on the front for stopping (what you should do anyway), or find a stiffer frame. PIA I know.

Mr.Gib

Your Factor O2 VAM Review was one of my favourite WW threads so the issue of frame stiffness is fresh in my mind. I should also mention that I don't think having a less-that-ultra-rigid rear wheel is the reason I haven't been signed by a pro team but I really dislike the sound of brakes rubbing and I love a super solid feel with granular feedback, ride quality be damned. Should I mention that I run my 25C tires at 100psi+

To your point about stiff wheels and brake rub, my understanding is that from most to least brake rub it goes like this - Ultra stiff rim with flimsy spokes (most rub) > decently balanced rim+spoke stiffness combo > Ultra stiff rim with excellent spoke bracing (hypothetically 60mm carbon with 32 x 14g spokes) for the lowest amount of rubbing.

As good as most of todays carbon wheelsets are I believe a comment that was posted in another thread suggesting that 'sexy sells', meamning that light weight wheelset with radial or innovative spoke lacing attracts buyers, but sometimes what looks lame on paper might work better on the road, like a slightly heavier rim with 24 thicker spokes. I can also see how a 175cm 65kg rider with a 1000w sprint wouldn't put nearly the same level of stress/torque/load/whatever into the wheel(s) as a 188cm 84kg rider with a 1500w sprint.

This wheel search would be easy for a disc set-up but I think us rim brakers are getting left behind.

This all makes good sense to me. Seems logical that the best scenario to fight brake rub is a robust frame and solid built wheel. The increase in gears has reduced bracing angles over the years making building a stiff wheel more of a challenge. But you should be able to manage it. I have three rim brake bikes with various wheels and zero brake rub. Up until about five or six years ago I was good for 1500 watts and never had a problem.

[BdaGhisallo]

Bontrager XXX 4 (47mm) and 6 (60mm) should still be available.

You beat me to it. These wheels are excellent and have a terrific braking surface.

[RedRacer]

Bontrager XXX 4 (47mm) and 6 (60mm) should still be available.

You beat me to it. These wheels are excellent and have a terrific braking surface.

Ok I'll bite. Compared to my Roval 50s the Bontragers are...

3mm shallower
2.4mm narrower outer rim width, 27mm vs 29.4mm (I only use 25C tires)
Two extra front spokes and three extrarear spokes
Approx 25g/set heavier (calimed) which is insignificant

The important questions are: Will they be stiffer and which wheelset is more aero?

[RedRacer]

Bontrager XXX 4 (47mm) and 6 (60mm) should still be available.

Sadly the Bontrager XXX 4 and 6 rim brake wheelsets have been discontinued and Trek has no stock. Back to square one

Are these still the three best options and if so which is the stiffest and fastest?

Bora WTO 60
1547g / 19mm internal, 26.5mm external
Spoke count Front/Rear: 18/21 (rear G3 pattern)

ZIPP NSW 404 (58mm)
1592g / 20mm internal, 26.4mm external
Spoke count Front/Rear: 18/24

ENVE SES 5.6
1593g / 20mm internal, 29mm external
Spoke count Front/Rear: 20/24

[tomato]

Blackinc, Princeton, Hunt, Knight