Rim vs Disc Brake Wheel Question

Ladies and Gents -

Got a question. All my road bike are currently rim braked, but I’ve recently been getting an itching to pick up a set up aero road wheels in the 45mm-60mm flavor. I haven’t decided on the exact ones, but am leaning towards Zipp 303 NSWs.

I’m planning on getting an aero-y road bike next season, so I don’t really want to put upwards ofr$2k in a current bike (which, for the record is a round tubed Ti bike, so not aero). What I was thinking to do was to buy a set of rim brake wheels or rims and then just change the hubs when I get a disc brake bike - anyone gone down this route? Any pitfalls or reasons it wouldn’t work?

Thanks for any help or advice…

Peter

From my understanding disc wheels are built very differently due to the braking forces.
I read something on some or other cycling site that With rim brakes the force is already on the outer circumference but discs move the braking force towards the centre of the wheel and that force is then transmitted through the spokes to the tyre eventually.
You could still argue that both wheels have to cope with the rider weight through the spokes but if I were you I’d hold off on the wheels and rather buy disc specific ones

As above, rim design can be different (better) for disc brake rims since they don’t have to handle braking duties directly at the rim. Not sure on the impact with the ones you mention?

Your idea isn’t really the best, although I understand the reason behind it. It can be done, but is not really the best long term solution, IMHO.

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One of the advantages of disc brake wheels is that it gives wheel designers a lot more freedom to optimize the rim shape for aerodynamics, rather than to provide a solid braking surface.

As the intended move is partly to get aero benefits, and NSWs don’t come cheap, I’d suggest waiting until next season, and go all-in for discs at that point.

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For racing or just to have?
My advice would to be get some disc wheels once you have a disc bike. I know you’re planning ahead. But. If you just want some aero wheels for racing, my suggestion is to score some tubulars or cilnchers (odds are you can even make them tubeless) and use them this year. You can find aero tubulars - and they’ll be very, very light - for super cheap. I have a set of Bontrager Aelous 5 that I got for $500.

I’d just save up and do it all at once. You’ll end up with better kit overall if you do so. This is the route I’m going.

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Yeh, my idea was to carry them over. I’m aware of some design considerations, but, from stuff I’ve seen the rim brake/disc brake wind tunnel data from the same manufacturers is similar… My biggest concern is actually aesthetics - be a shame to have some janky looking brake track on a nice new bike with disc-brake wheels.

I basically want some nice “aero-ish” wheels than handle themselves well in the wind and brake well in the rain. I am looking at clinchers with a tubeless rim profile. If you’ve got some recommendations that run closer to $1500 than to $2500, I’d be game to hear them. Reputable company with European distro is a must.

The other option I’m playing with is to look used or to do something like a set of Flo wheels (or other company). I guess I trust those Flo bros more mostly because of their media presence and reputation on ST, but who knows.

The biggest potential pitfall here is you may be limiting your tire width selection. One of the biggest advantages of disc bikes and rims is that they will accommodate nice wide tires and still be aero. Take the new venge for example. You can run 32mm measured tires (28mm labelled tires) on them. To have a rim aero/handling optimized for that tire, you’re looking at about a 32mm outer, measurements not capable with rim brakes.

The rim you mentioned is optimized for measured 25mm tires, which means 23mm labelled tires that balloon to 25mm. Personally, a true 25mm aside from a pure TT is too narrow in this day and age.

When deciding, I would start from the ground up at the tires as that has a huge impact of how the bike will feel. Ask yourself, what size of tire would you like to run, then build from there.

Also, rim brake carbon composition has compromise incorporated in its DNA whereas a disc brake is not held back by limits. The resin for rim brake varieties have to be optimized to resist failure from the heat of braking friction. Disc brake specific carbon rims have a higher modulus carbon that have properties superior to the rim brake version.

IMO, rim brake carbon will be irrelevant in time because there is no consumer material technology that has been able overcome the heat resistance trade offs. Aluminum rim brake builds already rival carbon in performance and looks.

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Thanks guys for all the opinions.

I think I’m gonna go with a Flo or other model wheelset and just keep it for the rim brake bikes. Get the nice wheels when I get the nice bike :slight_smile:

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