Aero Wheels for racing in the Alps (2022)

[FlatlandClimber]

Hi there,
I am planning to race in the Alps this coming summer. I have a beautiful climbing bike in the Aethos, with Extralitd 339 wheels (39mm depth). That's great for mountain TTs and days where the climbs are super steep.
However, not all climbs are >6% gradient, and there are gains to be had from going more aero.
I was thinking about using the SL7 for those days. I have raced the Rapide CLX in the Alps before and they are great. I recently crashed them though, and I am now looking for a new set of wheels.

My priorities would be:
- ~50mm front wheel (I am racing down the mountain as well)
- Should work well aerodynamically with a 28c tire
- TL compatible
- >1500g set weight (I'd love to have much lighter wheels, but I can't really find any)
- availability (first race in 3 weeks, but there are more to come).

I have so far eliminated all ZIPP wheels. I have 353 but they aren't as aero, the 454 are too deep.

The new Roval Rapide II are Great, but they are now >1500g, which I'd like to avoid.

The Shimano C50 Test fast, cost less than the others, and have the 12s specific free hub going for them. They weigh 1510g with valves and tape, and they are rather narrow (28, so 28c tire will be a penalty).

The new ENVE SES 4.5 look pretty tasty. They are likely not available on time and I'm a little unsure about the hubs. Not really looking great for €3k. They are the only rim optimized for a 28c here however.

Princeton Dual 5550 - Great weight, mega expensive,
Infinite lead time

So far, the Bontrager RSL 51 have emerged as what I see as the best option. They are ~1450g and wide enough for 28s to not be a problem (although still optimized for 25s).

Any advice, other options?

[SCJKJ]

I have contemplated this as well. I eventually pulled the trigger on some LightBicycle ones(AR55), but that suits my needs, yours might be different and I get the appeal of a branded wheel.

The new enve 4.5 looks like a good choice, although I'm still not a huge fan of hookless on road rims(I'd definitely use something like Vittoria's airliner, or whatever it's called). It's 32mm wide tho, so marketing aside, it's definitely less aero than the bontrager, the difference won't be huge, but cdA inherently has the 'A' factor, which is just bigger.

I think if you use a 5000S TR/regular 5000, the RSL51 will be the best choice. Good hubs that are easy to work on, 1410gr(trek specs), 31mm wide at the start of the rim and 23mm internal should make it ideal for a 28mm front and 30mm rear tire in my opinion.

[FlatlandClimber]

I am not sold on the "wider rims are less aero" thing.
Of course, a 10mm wide rim would be mega aero in a vacuum (not a literal vacuum ). But the 50mm wide down tube behind it gets hit by cleaner air now.
The Bontrager are likely a good choice though. 1450g with tape and valves though.
It's a 70g advantage over the heaviest wheels here really, which is ~10 seconds over a 120k/3800m stage.
Not huge, but all little helps.

[SCJKJ]

I am not sold on the "wider rims are less aero" thing.
Of course, a 10mm wide rim would be mega aero in a vacuum (not a literal vacuum ). But the 50mm wide down tube behind it gets hit by cleaner air now.
The Bontrager are likely a good choice though. 1450g with tape and valves though.
It's a 70g advantage over the heaviest wheels here really, which is ~10 seconds over a 120k/3800m stage.
Not huge, but all little helps.

I won't try to convince you, and honestly I'd take the slight penalty for more comfort and grip anyway, but even if the cd value gets a little better, it's just offset by the 'A'. The disturbance of the air is not affected by the width of the rim unfortunately. A bike tire never really fits into an optimal aero shape anwyay, so the wider you make it, the harder it becomes to keep flow laminar. As I said however, the difference won't be huge and comfort and grip are more important, definitely in the mountains.

The LightBicycle AR55 flyweight with CarbonTi hubs and cx-ray spokes with cx-sprint rear DS spokes, should be around 60-70 grams lighter still, but honestly don't know if you'd feel the difference. If you really want you just put the lightest casette on there and you lose some weight as well. All up to preference.

[mrlobber]

I am not sold on the "wider rims are less aero" thing.

I'm not sold yet either, however, my practical riding on flat, fairly smooth roads (where aero SHOULD trump everything) still indicates that 23mm tubs on shallow 8 years old Farsports rims are really close in average speeds to 28mm tubeless 50mm wheels (+ aero bike) except the odd super-fast day which looks rather an exception than a rule.

I was going to suggest Swisside Hadrons (or DtSwiss alternatively), however, just realized the 50mm version is only 27mm wide, and while Hadrons 625 are 30mm, they're heavy. So my vote goes to Bontragers too.

[Matte86]

I would stick with the Roval Rapide II.. as latest Ryan’s SL7 build they came at 1504gr.. honestly you can’t go wrong with them..
Princeton look fabulous, but their inner width isn’t the best with a 28.

[FlatlandClimber]

I had the hadrons on watch as well. I have the 800 front wheel for TT and it is really great, but than I had the same realization about the 50 being narrow and the 62 being heavy (and too deep for this case)

@Matte I know this isn't a bad choice. But you know, new stuff is also always interesting and it kinda feels like buying the same wheels again, just more expensive and heavier 2 years later
The wheels are fantastic no doubt.

[refthimos]

Sounds like your best bet might just be another pair of the Rapide CLXs (gen 1)

[C36]

Just to understand, why 28 tires? Especially for racing and if you seem to have an interest in shaving some weight and being aero?

[TobinHatesYou]

Many 25mm tires are going to balloon out to 28mm WAM on a the Aeolus RSL 51s anyway.

[tonytourist]

My 4.5 ARs on Enve hubs have been great. Lots of miles, zero issues. I think a set on DT 180s would be even better.
My 28 Rapid Airs measure right under 32.

[usr]

If you don't care, ride a fatbike, if you do, don't ride 28s

[jlok]

Mavic Cosmic Ultrimate UST?

[FlatlandClimber]

The fat bike comparisons are pretty wild. Several pro tour riders and World class triathletes have been using 28s for the past couple of years.
The added comfort of a wider tire is not to be scoffed at in a >5h race.
The lower pressure and wider contact point increase traction uphill, which I find useful when the road gets reall really step and you have to apply high torque.
The wider tires in general I find give more confidence when descending. Living in the flatlands, I am not a great descender to begin with, and I find narrow tires tend to give me this "on razor's edge" feeling in fast corners.

Also, many tires will blow up to 26, 27, 28 mm actual width. Especially Michelin is a known perpetrator of this, so it makes sense to have a wheel shape that allows for this to still be Aero.

[stevesbike]

Almost all the climbs in the Alps have good pavement (Sarenne is one exception that comes to mind) and I've done a few HR Alps on 25mm tubeless - never felt a need for anything wider. Unless you have some totally flat days, I also don't really see much need to go from a 39 to a 50 deep wheelset as the aero/weight cost-benefit doesn't seem worth it. As for descending, I can't see any significant advantage on a more aero wheelset - unless you plan on soloing off the front.