Aero rims and fat tires

Considering a set of Enve 3.4s for a mostly dirt road bike that will never see tires <35mm wide. With such tires do I lose all aero advantage? Should I just get a set of G23s? Will the G23s be as stiff and snappy on acceleration?

Thanks folks.

The 3.4’s will still be more aero than the G23’s……but when running wide tires like you describe, the aero benefits are diminished. To what degree is impossible to answer since it is very tire dependent.

But a more aero rim, as a rule, will always be more aero (assuming the same tire).

ETA - ENVE has a post on exactly this question (although it is about the previous generation 3.4’s. They say that the aerodynamics are essentially the same by the time you get to a 40mm tire.

The new 3.4’s have a wider internal rim width (25mm) than the G23’s…based on that alone, I would probably go with the 3.4’s.

seems like the latest version of the 3.4’s were virtually tailor made for what you’re talking about, no?

I have been racing and training gravel on my ENVE 3.4s/DT hubs for 3 seasons and they have been incredibly durable. They roll well, no sidewind issues even in gusty wind. Orange seal and 40 mm Pirellis, 35 mm Gravel kings. I have cut tires etc but never a rim problem despite putting then in some bad holes. I have also used them for long adventure days and they are not overly harsh with my Crux which is kind of a stiff bike. I have not ridden the G23s but super happy with the 3.4s. Obligatory podium shots for credibility
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(or lack thereof!!)

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To follow up on the answer above…

To achieve an aerodynamic benefit, you want a height-to-width ratio of at least 3:1. Ideally, it should be even higher, e.g., 5:1. If you are running at least 35mm tires (which we assume has a height 35mm), it means that you need a rim that is at least 70mm deep (for a total height of 105mm when accounting for the tire).

The Enve 3.4 has a height of 43mm (rear), so you will not get any aero benefit with such wide tires. According to Aerodynamics of Gravel Bikes ‘almost aero’ often is worse than not aero at all.

The Enve wheelset has a lot of nice properties (and deep wheels always look great), but being aero is not one of them for your application.

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