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Chinese Carbon Road Bikes => Cyclocross Frames, Wheels & Components => Topic started by: pandaGravel15 on March 30, 2026, 03:17:22 AM

Title: Fast gravel build: do 45mm wheels make sense for aero + climbing?
Post by: pandaGravel15 on March 30, 2026, 03:17:22 AM
Hi guys, I'm starting a new fast-gravel build and I'm obsessing over the wheelset. I’m aiming for something that’s aero enough for flat sectors but still reasonably light for climbing.

I’ve been looking at the https://it.aliexpress.com/item/1005005909542773.html (https://s.click.aliexpress.com/e/_c4sjknWH)

They claim around 1375g for a 45mm profile, which sounds pretty impressive for the price. On paper it looks like a great balance, but I’m a bit unsure about going that deep for gravel use.

Do you think 45mm depth actually gives measurable aero benefits at typical gravel speeds (~25–30 km/h), or is it mostly marketing at that point?

Also curious if anyone has real-world experience with similar depth wheels off-road.
Title: Re: Fast gravel build: do 45mm wheels make sense for aero + climbing?
Post by: Requiem84 on March 30, 2026, 03:28:02 AM
The aero benefits will depend a lot on rim width and which tire width you will run.

I have 50mm deep rims and they have survived a lot of abuse. No issues in going deeper on gravel for me.
Title: Re: Fast gravel build: do 45mm wheels make sense for aero + climbing?
Post by: kubackje on March 30, 2026, 06:19:02 AM
Hi guys, I'm starting a new fast-gravel build and I'm obsessing over the wheelset. I’m aiming for something that’s aero enough for flat sectors but still reasonably light for climbing.

I’ve been looking at the https://it.aliexpress.com/item/1005005909542773.html (https://s.click.aliexpress.com/e/_c4sjknWH)

They claim around 1375g for a 45mm profile, which sounds pretty impressive for the price. On paper it looks like a great balance, but I’m a bit unsure about going that deep for gravel use.

Do you think 45mm depth actually gives measurable aero benefits at typical gravel speeds (~25–30 km/h), or is it mostly marketing at that point?

Also curious if anyone has real-world experience with similar depth wheels off-road.

Tagoola AR xplr wheels are my top choice on the market. I have them in 50mm and they've been great so far
Title: Re: Fast gravel build: do 45mm wheels make sense for aero + climbing?
Post by: jfcb on March 30, 2026, 06:33:54 AM
Yes it makes sense, though the bigger your tire the less effect it will have. If you run mtb tyres, I wouldn't mind too much about the rim depth, especially at speed below 30km/h.
As for reallife experience, but totally on feeling, I do notice the difference between my low profile (old mtb wheels) and 50mm gravel wheels (same width with 45mm fast gravel tyres).
45mm is a good sweetspot. I do notice a difference in compliance between my 40mm and 50mm gravel wheels, but they are still perfect for gravel.
Title: Re: Fast gravel build: do 45mm wheels make sense for aero + climbing?
Post by: jonathanf2 on March 30, 2026, 10:27:52 AM
Hi guys, I'm starting a new fast-gravel build and I'm obsessing over the wheelset. I’m aiming for something that’s aero enough for flat sectors but still reasonably light for climbing.

I’ve been looking at the https://it.aliexpress.com/item/1005005909542773.html (https://s.click.aliexpress.com/e/_c4sjknWH)

They claim around 1375g for a 45mm profile, which sounds pretty impressive for the price. On paper it looks like a great balance, but I’m a bit unsure about going that deep for gravel use.

Do you think 45mm depth actually gives measurable aero benefits at typical gravel speeds (~25–30 km/h), or is it mostly marketing at that point?

Also curious if anyone has real-world experience with similar depth wheels off-road.

I ride dirt fire roads and single track with lots of ruts, baby heads and jagged rocks. 45mm depth has been okay surviving in those conditions. In terms of aero I think other factors come into play for gravel.

I'd also consider shorter crank lengths and narrower bars for the flat sections. I'm currently running 34cm drop bars (46cm flared drops) with 155mm cranks on my gravel bike. On the flats, narrow bars help get into an aero position, while the shorter cranks allow higher cadence in the wind. When trail climbing, I have wide drops for stability and the shorter cranks help avoid banging into rocks and spinning up loose gravel section while maintaining traction.
Title: Re: Fast gravel build: do 45mm wheels make sense for aero + climbing?
Post by: Daisy- on March 30, 2026, 09:47:20 PM
Hi guys, I'm starting a new fast-gravel build and I'm obsessing over the wheelset. I’m aiming for something that’s aero enough for flat sectors but still reasonably light for climbing.

I’ve been looking at the https://it.aliexpress.com/item/1005005909542773.html (https://s.click.aliexpress.com/e/_c4sjknWH)

They claim around 1375g for a 45mm profile, which sounds pretty impressive for the price. On paper it looks like a great balance, but I’m a bit unsure about going that deep for gravel use.

Do you think 45mm depth actually gives measurable aero benefits at typical gravel speeds (~25–30 km/h), or is it mostly marketing at that point?

Also curious if anyone has real-world experience with similar depth wheels off-road.
45mm depth is suitable for the speed, 50mm maybe don't take its advantage, there is lighter than 1375g
https://serenadebikes.net/700c-gravel-wheelset-45mm-depth-31mm-wide-clincher-rims-SR042-hub-p5242733.html
Title: Re: Fast gravel build: do 45mm wheels make sense for aero + climbing?
Post by: stalkersk on March 31, 2026, 03:37:20 AM
I am currently running 64mm deep and 32mm internal width rims and it is positive jump from 25mm internal I had previously. I personally would look for something wider internally 28-32mm, with 40mm tire it stretches to 42mm on 32mm rim. Depth depends how comfortable you are in the wind. I have been running 65mm wheels for years, but my gravel wheelset has 1480g with brass nipples, which is in the end lighter than my old road set.

I had no issues keeping up with friends on road using 45mm G-One R and RS Pro (F/R) (48mm actual width), on rougher stuff it is a blast and I still am at the point going lower with pressures.
Title: Re: Fast gravel build: do 45mm wheels make sense for aero + climbing?
Post by: jfcb on March 31, 2026, 04:03:16 AM
Thanks, that’s really helpful insight.

So in your opinion, for these wheels https://it.aliexpress.com/item/1005005909542773.html (https://s.click.aliexpress.com/e/_c3mjN3dj), would the 38x32.5 be the better choice if I plan to run 40–45mm tires?

Yes, I would consider 25mm internal width  the minimum nowadays for 40-45mm. Have a chat with Peter from XMCarboonspeed (search for him on the forum if you dont know him), he can give you great deals as well.
Title: Re: Fast gravel build: do 45mm wheels make sense for aero + climbing?
Post by: jfcb on April 01, 2026, 07:43:53 AM
From what I’m seeing, this rim has a 22/24mm internal width, so I guess it’s not something you’d recommend, right?

I don't think you will notice the difference between 24 or 25mm, my point was more on being future proof in case you want to move to wider tyres in the future (in case your frame can accept it). Then, I would'nt buy a more narrow rim today.
Title: Re: Fast gravel build: do 45mm wheels make sense for aero + climbing?
Post by: ChinerStevie on April 02, 2026, 12:05:21 PM
What internal width do you recommend for 40-45mm tires?
Title: Re: Fast gravel build: do 45mm wheels make sense for aero + climbing?
Post by: Alancik123 on April 18, 2026, 03:56:05 AM
I don't think I've fully understood, so I'm continuing to evaluate this https://it.aliexpress.com/item/1005009234951911.html (https://s.click.aliexpress.com/e/_c42jBL3T), which I think is fine. In any case, regarding aerodynamics, I’ve realized that the external width is what matters most.

Love these rims, I ran 50mm Schwalbe rx pro on them from 1.5 bar all the way to 1.0 bar numerous times it's amazing how well they ride even with such low pressure.
Title: Re: Fast gravel build: do 45mm wheels make sense for aero + climbing?
Post by: bastianb on April 23, 2026, 12:39:51 PM
Hi, you should contact Bitranz. I currently ordered a 1390 grams, 24 spoke wheelset, 32mm inne width, 38mm outer. They are offering 45-60 mm depth.
I think you will profit most from a wheelset around that 40mm outer width.

My experience is they build great quality, these will be the third pair. Spoke tension and finish was awesome. Just ready to ride.
Title: Re: Fast gravel build: do 45mm wheels make sense for aero + climbing?
Post by: Samuel BMR on April 27, 2026, 02:45:12 PM
32mm internal, 41mm external, 50mm Deep for 1280g. Under 700€

Happy days
Title: Re: Fast gravel build: do 45mm wheels make sense for aero + climbing?
Post by: Ada on April 28, 2026, 01:04:29 AM
I bought a pair of 50mm rim depth Tagoola xplr tires and have ridden about 200-300 kilometers so far. They feel great and perform very stably on gravel roads.
Title: Re: Fast gravel build: do 45mm wheels make sense for aero + climbing?
Post by: kubackje on April 28, 2026, 09:22:16 AM
Are these the ones you mean? https://it.aliexpress.com/item/1005011954627437.html (https://s.click.aliexpress.com/e/_c43roGXN) They are quite expensive, though!

I think he's talking about these I just found this on AliExpress:
AR XRLP Light Gravel Carbon Wheels Ratchet System 54T NBK bearing Hub 32mm inner Width CXRAY Hooked Bicycle Carbon Wheelset
https://a.aliexpress.com/_EyN8oto

I got them for under 500$ during sale with coupons.
Title: Re: Fast gravel build: do 45mm wheels make sense for aero + climbing?
Post by: Ada on April 29, 2026, 03:38:54 AM
Yes, that's the one. How did you get it for such a low price? Did you use some hidden coupon?
Title: Re: Fast gravel build: do 45mm wheels make sense for aero + climbing?
Post by: Leo.D on June 23, 2026, 03:30:11 AM
the rough rule of thumb that's held up across a few wind tunnel tests: for a given rim, the aero benefit starts evaporating once your mounted tire measures more than ~105% of the rim's external width. So a 38mm external rim with a 40mm tire (105% match) will perform noticeably better than that same rim with a 45mm tire (118% — the airflow detaches at the tire-rim junction).
Title: Re: Fast gravel build: do 45mm wheels make sense for aero + climbing?
Post by: hubba on June 24, 2026, 05:46:58 AM
The rule of 105 was that the rim needed to be about 105% of the tire for it to re-attach the airflow. Not the other way around. But with modern rim profiles it's not so true anymore but still a good starting point. And if a rim is deep enough even if it's a lot narrower than tire it will still help even with wide gravel tires.
Title: Re: Fast gravel build: do 45mm wheels make sense for aero + climbing?
Post by: Alancik123 on June 24, 2026, 11:55:26 AM
S,o what you're guys saying, I need a rim with 50mm external to ride 55mm tyres at maximum aero efficency??  ;D
Title: Re: Fast gravel build: do 45mm wheels make sense for aero + climbing?
Post by: lidation on June 24, 2026, 12:25:12 PM
I just think that the 105% rule is just marketing BS for average amateurs who don't race.  Look at our bodies, even the fittest person have a much larger cross-section than the wheel/tire. Plus, with any hills, the climb speed won't matter in terms of aerodynamics.  On the downhill, gravity is helping so aero is playing a secondary factor anyway.
Title: Re: Fast gravel build: do 45mm wheels make sense for aero + climbing?
Post by: hubba on June 24, 2026, 12:36:40 PM
Yeah the savings are tiny but still there. Having a tire few mm wider than the rim vs few mm more narrow is only a few watts. Aero socks might save you more watts than that. But it's also a wheel stability thing, a well matching rim and tire behaves better in the crosswinds.