Rim profile choice - gravel

[SteelToe]

Narrowed it down to these two, running 45mm semi-sleeks for paved and very light gravel.
A mix of flat and climbs.
Only a few grams difference between these set. What do you think?

[Tijoe]

There are several things a play when you go to select a rim.

1. I assume this rim is only for your rear wheels having the 2.8mm offset.
2. Deeper dish rims can be better for gravel bikes.   
- For gravel grinders riding on mixes gravel and asphalt roads, shorter spokes make a stiffer wheel. You can adjust the wheel stiffness by lacing either 2X or 3X pattern. 
- Rim could be more aerodynamic.
3.  The internal rim width/overall rim width, makes a difference in 2 things.
- The maximum width tire you can install on the rim.
- The wider rim width can be used to create a stiffer tire sidewall when you are using narrower tires.  Wider versus narrower rims can help reduce or increase tire rolling resistance.
4.  If you are planning on riding on singletrack or rough gravel roads,   a narrower rim with a wider tire will allow the tire's sidewall to flex more at lower tire pressure.   (This often increases tire rolling resistance on smooth surfaces.

I don't have time to look up a few links, but there are several sites that list recommended tire widths versus rim widths, and perhaps explains better what I am trying to convey above.

For my hardtails and and Full suspension bikes, I have built up 3 different sets of wheels, that have narrow, medium, and wide rims, and I will swap wheels depending on the terrain, tires needed for traction or smooth rolling that I plan to ride.   

For my gravel bike, I have stuck with narrower rims because I only run up to 42mm tires (running 40 wide now) I ride this bike on smoother gravel roads and asphalt.  When the going gets tough, I use my 29er hardtail with a rigid carbon fork.  I've been running featherweight 27mm wide/22 inner width with 50mm wide low rolling resistance tires.  Due to the wider sidewall bulge, I seldom, if ever have rocks hit the rims.  I've used this combination for years bikepacking with great success. 

On my gravel bike, I have run these wheels for over 5 years.  Inexpensive and very durable  https://www.aliexpress.us/item/2255799847268989.html
28mm wide, 21mm internal width. 

[SteelToe]

Thanks @Tijoe,

According to ETRTO, for 45mm tyres 25iw rims are ideal and 27iw rims are "possible".

Currently 45mm Gravel Kings SS measure 48mm wide on the stock 25iw Alu rims. Even if they go a little wider there's still enough clearance frame / fork clearance, my concern - tyres forming "bell" shape: https://bikerumor.com/tech-story-match-bicycle-tire-width-rim-width-best-results/

Also, considering the abovementioned rims, I'm sceptical of the system weight ratings of 120kg (Standard) & 110kg (Fly) - I don't know if the manufacturer infact tested these, or it's some form of an estimate / guess. Other manufactures state 90kg limit for the Fly versions.

[SteelToe]

Forgot to add - the 25iw rim profile has an arc leading to the rim flange on the outside, the 27iw variant has almost vertical walls...
Thinking the 27iw would be the preferred option from the aero (most likely negligible) and aesthetics perspective?

[Daisy-]

Narrowed it down to these two, running 45mm semi-sleeks for paved and very light gravel.
A mix of flat and climbs.
Only a few grams difference between these set. What do you think?

45mm tire size is suitable for 24mm internal, or wider internal 30mm if possible

[stalkersk]

I have Eeasedon 64mm and 32mm IW rims, love the way how they ride, currently set up with Schwalbe 45 G-One R Pro at front and RS Pro at rear, they have 48mm measured it is a proper weapon. I would ditch assymetric rims, the spokes are shorter, so that has not as big impact with angles as shallow rims.

[jfcb]

If I'd had to choose between those two, I'd say take the higher, wider rim. No need to go wider than 27mm.
Some people tend to go super wide, but forget to take into account that the wider you go, the lower the tyre height will become and the more chance for pinch flats you will have.
Concerning spoke offset: not a must, not noticable better or worse, as long as you use the right spoke length.

[stalkersk]

The pinch flats issue on wide rims is IMO purely due to how Zipp designed the hooks on the rim, look at some closeup how sharp they are. That is why I chose hooked version of the rims. I had really hard hit on a road where the tire was 1mm narrower than rim (31mm WAM) and only result was crack in the rim, which I noticed at home after the ride, which was more than 50km after the impact.

[ChinerStevie]

What internal width do you guys suggest for gravel (40-45)?
And what do you think of the asymmetric profile of this thread?

[Tijoe]

What internal width do you guys suggest for gravel (40-45)?
And what do you think of the asymmetric profile of this thread?

I recommend you take a look at a TIRE & RIM Compatibility chart like this one:
https://www.wtb.com/pages/tire-rim-fit-chart?srsltid=AfmBOoppqV1Gz-5a3k277G79YNgV6fJ56N49qUYF79JZLAqyjHnPry01

Concerning asymmetric rims,   You would never need to use one for a front wheel.    Rim offsets are used for rear wheels.

An asymmetric rim has a larger impact on wheel build strength for narrower hubs like 130 and 135.  As you migrate to 142, 148 (Boost) and 157 (super Boost), these wider hubs often have wider spaced flanges, and closer-to-equal length left-side to right-side spokes,  that help to build a stronger wheel, due to more even spoke tensions between the left and right side of the wheel.

[SteelToe]

I recommend you take a look at a TIRE & RIM Compatibility chart like this one:
https://www.wtb.com/pages/tire-rim-fit-chart?srsltid=AfmBOoppqV1Gz-5a3k277G79YNgV6fJ56N49qUYF79JZLAqyjHnPry01

Concerning asymmetric rims,   You would never need to use one for a front wheel.    Rim offsets are used for rear wheels.

An asymmetric rim has a larger impact on wheel build strength for narrower hubs like 130 and 135.  As you migrate to 142, 148 (Boost) and 157 (super Boost), these wider hubs often have wider spaced flanges, and closer-to-equal length left-side to right-side spokes,  that help to build a stronger wheel, due to more even spoke tensions between the left and right side of the wheel.

My argument for asymmetric - less spoke tension difference between the sides... think the symmetric difference is typically 50%, while asymmetric is about 20%?

I don't think it'd hurt to go asymmetric at the front either - the brake flange also takes up a bit of space. My Turbine MTB wheels are both asymmetric.

[ChinerStevie]

So which one did you decide to  take?

[SteelToe]

So which one did you decide to  take?

https://www.aliexpress.com/item/1005007990155832.html but without the spoke holes and the new R310SL 52T + brass nipples. By my estimates the set should weigh about 1480g... Will report how it is once they're in my hands.