Performance difference between 25, 35, and 45mm deep rims?

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Catagory6
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by Catagory6

title kind of says it all

is there any good documentation out there?

threads in this forum?

by Weenie


AJS914
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by AJS914

You haven't read the Hambini topic?

AJS914
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by AJS914

Here is his blog post. Deeper is faster.

https://www.hambini.com/blog/post/bicyc ... s-fastest/

Catagory6
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by Catagory6

AJS914 wrote:
Wed Oct 17, 2018 5:08 pm
You haven't read the Hambini topic?
All those wheels looked like they were deeper than 45mm, looked like lot of tech stuff that flew over my had
Will give it another go

AJS914
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by AJS914

The chart starts with a Mavic Ksyrium which would be equivalent to your 25mm rim and includes various 35mm and 45mm wheels that you can compare it to. You don't have to read anything. Just look at the wheel charts:
Image
Image

Catagory6
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by Catagory6

AJS914 wrote:
Wed Oct 17, 2018 7:51 pm
The chart starts with a Mavic Ksyrium which would be equivalent to your 25mm rim and includes various 35mm and 45mm wheels that you can compare it to. You don't have to read anything. Just look at the wheel charts:
Image
Image
I saw that chart, all the wheels look to be deeper section than I'm looking for.

Currently debating the NOX Falkor 36 and the FSE 35mm

Still reading through the Hambini thread. Lots of stuff flying right over me though. I'm not very smart

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silvalis
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by silvalis

There are really only 3 takeaways from that thread.
1. Deeper = faster
2. Wider = faster
3. Unless they screw up the gap between the tyre and the rim (hence the hunt and flo results)

I would make your choice between those two rims based on the braking quality, hub, weight and price.
Chasse patate

AJS914
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by AJS914

Catagory6 wrote:
Thu Oct 18, 2018 1:16 am
I saw that chart, all the wheels look to be deeper section than I'm looking for.

Currently debating the NOX Falkor 36 and the FSE 35mm
There are several 35mm rims on the chart which you can compare to the base Ksyrium rim. It's basically a 4 watt savings at 30km/hr, and 15 watts 50km/hr. If the goal is to save watts I'd go deeper.

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wheelsONfire
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by wheelsONfire

I would go for braking and wider rims (more stable).
If you want wheels rather easy to find cheap, Easton Aero 55 tubular. The clincher version weight is alot more.
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jfranci3
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by jfranci3

The difference is small head on, but you get a lot sail area when in cross winds. If the rims are the same relative shape, you'll get better steady state crosswind performance out of deeper wheelsets. Deeper wheelsets tend to stall aggressively as they are turned too far into the wind. The differences you can see in any aero test you believe in, but the shape and width are more important than the exact depth.

Basically 10% difference at 50kph from “a” road wheelset with a bit of a V to what you should expect out of a TT 80mm wheelset. You get a lot of that just by shaping the rim better and adding a touch of depth. You lose most of it with the wrong tire size
Last edited by jfranci3 on Fri Oct 19, 2018 11:27 pm, edited 1 time in total.

hambini
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by hambini

From the thread

Deeper is faster unless they screw up the profile but wider is not faster.

Wider is slower but the fixed tyre width (23mm) means you need to optimize for that size

by Weenie


Hexsense
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by Hexsense

Wider wheel (than needed by the tire width) is slower.
Needed width for 23c tire is not much, easily achieveable by most modern carbon wheelset.

Story change when your road demand 25c, 28c and you want to keep it aero. Wheels from multiple years ago are generally too narrow. Wider (than wheel design for 23c) become faster to a point when it's already plenty wide.
See Shimano C60 against Enve 7.8, Enve is wider and perform better with 25c...
here: https://weightweenies.starbike.com/foru ... 5#p1432819

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