What would you miss more - comfort of 28 mm tires or convenience of tubeless?

Rider profile: late thirties, 84 kg, road cycling for three years, 150-200 km weekly, solo rides 60-120 km, mostly rolling terrain, no racing, endurance riding, averaging 28-31 km/h

Bike: Canyon Endurace, CF frame, disc brakes, full Ultegra R8000, carbon aero cockpit (H31), split carbon seatpost (S15 VCLS 2.0 CF), aluminium Mavic Ksyrium Elite UST

Reason for upgrade: increase in speed/distance, without compromising comfort and convenience, bling factor

Wheel requirements

  • mid-depth 40-50 mm aero, carbon, disc
  • optimized for 28 mm tires (external rim width 30-31 mm): lower rolling resistance, more comfort, better grip, currently riding 28 mm tires (never really ridden 25 mm), general trend points towards 28 mm, not really willing to go backwards
  • tubeless: big fan of road tubeless, Mavic UST on my current wheels works perfectly
  • long term serviceability

Choice narrowed to these two below. Advantages/disadvantaged listed in the level of importance (to me).

Cosmic Pro Carbon UST Disc
(45 mm deep, 19 mm inner width, 28 mm outer width, 1.650 grams, Mavic hubs, straight pull spokes, aluminium nipples)

  • optimized for 25 mm tires: loss of comfort, higher rolling resistance, (28 mm tires could be used, but then aero advantage is lost))
  • UST, problem free tubeless installation, from personal experience
  • easy access to service and spare parts: Mavic dealer in the neighborhood
  • deeper choice (45 mm), more aero - possibly annulled by higher rolling resistance tires
  • comes with Mavic Yksion Pro tires (poorer performance compared to Conti GP5000TL of the same width)
  • 3 year warranty (draw - most manufacturing defects manifest during initial period of usage, canā€™t imagine lot of defect that occur after three years of use and are covered by limited manufacturer warranty)
  • 1.199 EUR (tires and sealant included)

Reynolds AR41 DB
(41 mm deep, 21 mm inner width, 30 mm outer width, 1.630 grams, Reynolds TR2 hubs, Sapim sprint spokes, brass nipples)

  • fully optimized for 28 mm tires: full comfort and low rolling resistance
  • probable issues with tubeless installation: no confirmed compatibility, forums report experiences from ā€œimpossibleā€ to ā€œnightmareā€
  • questionable service in Europe (reynoldscycling.com lists only USA dealers, reynoldscycling.eu points to single service center in Germany, in late 2018 Reynolds was acquired by Hayes so Hayes service network will be integrated but such integrations are usually messy in the beginning)
  • narrower choice (41 mm), less aero - possibly annulled by lower rolling resistance tires
  • if mounted with Conti GP5000TL: best in class performance on 28 mm tubeless tires
  • lifetime warranty (draw - most manufacturing defects manifest during initial period of usage, canā€™t imagine lot of defect that occur after three years of use and are covered by limited manufacturer warranty)
  • 1.199 EUR (without tires, pair of Conti GP5000TL and some sealant would be additional 120 EUR, not very important)

Looks like hit and miss both ways.

If I go with Mavic and donā€™t find 25 mm tires comfortable enough, I can switch to 28 mm, but aero penalty kinda kills the point of aero wheels in the first place.

If I go with Reynolds, tubeless could be a PITA (most probably), I can ditch tubeless and just go with tubes, but I loose convenience of tubeless.

Not really considering other wheels options - if Iā€™m forced to go to 25 mm tires, only UST can justify it. On the other hand, if Iā€™m ditching UST, I wonā€™t do it for another set of 25 mm optimized wheels.

What would you miss more - comfort of 28 mm tires or convenience of tubeless?

Not trying to throw a wrench hereā€¦but there are so many wheels that take 28mm easily AND tubeless, that I donā€™t know why youā€™d limit yourself.

I ride 28s on three different bikes and they all take tubeless.

Are you completely wedded to only these 2 wheels?

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Actually, there arenā€™t that many mid-depth aero wheels that will take 28mm tires without aero penalty.

You need rim with internal width 21 and external width over 30 mm. AFAIK, only Enve 4.5 AR (far out of the price range) and Reynolds AR range. Both are tubeless ready, but thatā€™s about it.

If you know any others that fit the billā€¦

Hunt will be releasing there new 48 limitless which is designed for 28c specifically

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Itā€™s not just the comfort of 28mm v 25mm. The self-sealing aspect of tubeless works better at lower pressures, so in moving to 25mm, you will be losing some of the advantages of tubeless.

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Bontrager may have some options.

The Aeolus XXX 4 TLR is one, but perhaps out of price range? Not sure, but local shops may discount.

The Aeolus Pro 5 TLR are a lot cheaper, but only 19.5 mm inner.

3Tā€™s new Discus C45 wheels are optimized for tubeless and wide tires, so they seem to tick all your boxes. 3T have specifically tested them with very wide tires, too, and shown that the penalty is quite small.

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For the riding you are doing especially the no racing part I would spend that money on a riding trip somewhere new. That is where my bike money goes these days.

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25mm internal width is the new black :wink:

Your frame can handle the width. These types of wheels are the true advantage of disc brakes IMO. Get that wide tire, get tubeless if you want, get the aero advantage of following the 105 ruleā€¦you can have it all! Itā€™ll be glorious. I reckon Iā€™ll pick myself up a pair of Novembers when the time comes.

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+1 on November wheels. I have a few sets, going to add a set of Cafe Racers soon. 28mm tubelessness for my Stigmata on the road.

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Interesting notion here: https://www.bicyclerollingresistance.com/specials/grand-prix-5000-comparison

See chapter: Rolling Resistance at the Same Comfort Level (4.5 mm tire drop)

25mm tire @ 87psi/6.0bar vs 28mm tire @ 81psi/5.6bar = same comfort level (?!) and rolling resistance

Iā€™ve always assumed that lower pressure equals more comfort per se.

25mm on the front for aero 28mm on the back for comfort.

Check out the new Cannondale wheels for systemsix. I think these should fit the bill.

Yup, love the company and had 3 rim brake builds with them. Are those cafe racers going to the regular ones or are you going for the ā€œAll Roadā€. Iā€™ve been waiting for those 25mm internal builds and am seriously considering picking up a set.

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I think before you say a 28mm tire on a given rim profile is slower you really need to know SPECIFICALLY what the aerodynamic disadvantage is vs the rolling resistance advantage. The move from 25mm to 28mm width tires has very definite & non-trivial watt savings. That may or may not be partially or completely offset by the aerodynamic disadvantage of the tire width/rim profile combo.

In general, I would say that so long as the measured width of your tire at pressure is less than 95% of the measured width of the outside of your rim profile at itā€™s widest point. (If itā€™s a modern toroidal rim profile) So if your tires really are 28mm at pressure then your rim profile should be 29.5mm or more to avoid ā€˜Rule of 105ā€™ consequences.

But what are those consequences? Wellā€¦at wind angles in the 10 degree to 18 degree range probably 40 to 60 grams of drag. Thatā€™s in the case where your tire width starts to exceed your rim width. In that more moderate range where tire width is 100% or less but more than 95% of your rim profile AND wind angle is in the low to mid teens weā€™re talking about a couple of watts. Ok, so tire>rim & 15 degree wind angle ā†’ 5 wattsā€¦tire~rim & 15 degree wind angle ā†’ couple watts.

Ok, what do you get for that? Well, at similar & reasonable pressures on typical asphalt you get about a watt per tire advantage in rolling resistance from the 28s. Thatā€™s the part we can quantify. Qualitatively you get additional comfort (thatā€™s the part you can feel!). So even if your rim might not be completely optimized for a 28mm tire, as long as itā€™s not ridiculously narrow vs the actual width of the inflated tireā€¦itā€™s a wash from an aerodynamic/rolling resistance perspective. Feel free to opt for comfort.

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Oh, I didnā€™t know about that. I guess the plot thickens. I usually ride my Stigmata with Spesh 30/32 tires that measure 35mm, I was thinking Iā€™d get a set of skinny rim wheels for true road tires but now Iā€™m thinking of something more interesting.

With the right rims, there is no aerodynamic disadvantage with 28 mm tires. Most aero rims have been designed for 25 mm tires, so going wider incurs an aerodynamic penalty as you write. But there are plenty of rimes (e. g. Enveā€™s 4.5 ARs or 3T Discus C45s) that have been designed with 28 mm tires in mind, and I donā€™t think there is any aerodynamic penalty whatsoever.

Plus, nowadays many manufacturers look towards wider tides to increase compliance with aero frames (arguably the 3T Strada was the first of the bunch here), i. e. instead of building compliance just into the frame, you rely on wider tires with lower pressures to provide more comfort.

Totally agree with you. But, itā€™s only beginning to emerge as a trend. Other than Enve and 3T that you mention (both on the higher end of the price range) and Hunt Limitless 48 mentioned in this thread, what else is out there that is designed with 28mm tires in mind? Besides Reynolds AR series?

Looks to me that market is developing in that directions, but could be smart to wait for other wheel manufacturers to catch on. How fast that could happen? Thatā€™s clearly connected to aero frame development that you mentioned. I guess wheel manufacturers need the market of frames to fit wheels in.

Interesting timesā€¦ :smiling_face: It might be wise to postpone wheels purchase for a while and see what market brings out.

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You are right that there are a only a few wheels that tick all the boxes. But I think if you can afford them, each one of them is a solid choice, albeit not cheap. (I donā€™t know how much the Hunts will run you, but the Enve are infamously expensive at $2,500+. The 3Tā€™s are slightly cheaper at $2,000.) Oh, and it seems that Enve also offers slightly less deep SES 3.4 ARs that have also been designed around 28 mm tires.

Yup, itā€™s a recent release and I think they begin shipping out by the end of the month. For half the price of the Enve 4.5 AR itā€™s going to be hard to beat. I want to get the ā€œAll Road 50sā€ but Iā€™m not sure how much of a difference itā€™ll be compared to my stock Roval C38s. Of course you can always just ask Dave what he recommends. There are some in this world that think your 35mm tires are ideal for road. Whatā€™s the width of tire youā€™re trying to run?