medium wide rims with 21mm tires

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Phill P
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by Phill P

The trend at the moment is for everybody to move towards 23-25mm wide rims which open out a 23mm tire for increased contact patch increased comfort and decreased rolling resistance

what about 22mm wide rims with 21mm wide tires?
How do they ride? Guess nobody does a tubeless 21mm tire....
Would be a large weight saving over 25mm wide rims and 23mm wide tires

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WMW
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by WMW

I guess you are talking about clinchers? A wide rim doesn't give you more comfort... unless you reduce pressure and/or put on larger tires. There might be a tiny rolling resistance improvement... but not if you reduce pressure. Better aero performance with 23mm tires and better cornering feel are the main benefits.

You can put 20 or 21mm tires on your 23mm rims if you like. Most people have no interest in the small tires though.
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Phill P
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by Phill P

What I was getting at is that is seems a 23-25mm rim with 23mm clinchers seems to give the ride and traction of a 25 on a "narrow" rim, but with better aero and no flop on the corners (not sure if net weight is better in all cases)

So will a 22mm wide rim with 21mm clinchers ride like a 23mm tire did on a narrow rim.

I think Zipps first "wide rims" were optimised for 21mm tires but the market still wanted to use 23mm tires so they went wider again.

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Calnago
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by Calnago

@Phill P: I would say you are correct on all counts. One of my favorite wheelsets is currently 25mm Veloflex Arrenbergs on Campy Boras. They seem to stabilize the Boras in a noticeable way. I've been experimenting a lot with these and another set of exactly the same wheels but mounted with 23mm Veloflex Carbons. The difference in comfort is of course noticeable but it is the difference in stability at speed that I'm most impressed with. Not sure why that is, but I like it. I guess if Reynolds can claim that tiny little "lip" helps stabilize the wheel then perhaps the added roundness up front with the larger tire does the same thing. :noidea: I can't say which set is actually faster... that would be splitting hairs. But I'll keep some data for both sets and over time maybe I'll be able to tell, not that it really matters that much to me unless I know I'm going to be going for a ride with my favorite sprint section involved.

The wide rim technology really benefits clinchers and does nothing for tubulars as far as I can tell. I had a set of HED Belgium clinchers which were really nice rims. I mounted some 25mm Conti Four Seasons on them for winter and found that there wasn't enough clearance with the fenders I was running. This was odd because I was running them just fine on a set of Campy Neutron rims. So I removed the tires off the Belgiums and mounted them on the Neutrons. Sure enough, the clearance was fine. So, I had to use 23mm tires on the Belgiums which looked just as big as the 25s on the Neutrons, which is consistent with what you are saying. I think the wide rim technology does in fact enhance the ride of a clincher a bit. But not so with a tubular. I still love my tubulars on standard size rims, much more than a clincher on a wider rim. I sold the Belgiums last year, not because they were bad wheels at all, just because I hated always having to readjust the brakes to accommodate the wider rim. And it was more than just opening up the calipers a bit, because if that's all you do, then the pads will not hit the rim exactly flush anymore without some adjustment that way as well.

But as @WMW, most people do not have a lot of interest in 21mm tires these days but if you did run them on 22mm rims I think I'd be a little worried about bottoming out on anything but the smoothest of roads. I do know a guy, and not a light guy by any means, who does in fact ride 21mm tires on a set of Lightweights. That's gotta be harsh, but I guess it's what he's used to.

Are you actually going to try this combo, or were you asking primarily for interest? If you try it, report back with your thoughts.
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Phill P
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by Phill P

I was just curious - because this is weight weenies afterall and this wide rim trend pushes weights up a little.

Going to a not as wide rim and 21mm tires would I assumed have given the ride of a 23 by possibly better aero

But you are right, I had not considered the "pinch depth" would be smaller on the 21s so you would still have to run higher pressures.

kulivontot
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by kulivontot

Wide rim shapes is completely about aerodynamics. The fact it spreads the clincher bead is simply an after effect.

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WMW
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by WMW

It's also notable that most riders believe that if a pro puts a 25mm tubular on his wide rims, then that is what they should put on their clinchers to be the same... but tubulars don't get bigger on wide rims, while clinchers do. So stick with your 23s...
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LouisN
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by LouisN

+1 IMHO

Louis :)

KLabs
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by KLabs

Phill P wrote:The trend at the moment is for everybody to move towards 23-25mm wide rims which open out a 23mm tire for increased contact patch increased comfort and decreased rolling resistance

what about 22mm wide rims with 21mm wide tires?
How do they ride? Guess nobody does a tubeless 21mm tire....
Would be a large weight saving over 25mm wide rims and 23mm wide tires

Hi Phill P, I use the Conti Attack 22mm tyre (front) on a 22mm clincher rim and run it at the same pressure as I would a 23mm tyre. My impressions are that it rides better than the 23mm tyre and is more responsive and stable on descents, especially cornering. I use a 23mm or larger on the rear rim.

thank KL :)

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