Carbon 29er vs 700c rims for tubeless gravel & cx

[sparky33]

What is the view on using carbon xc 29er mtb rims for tubeless 700c cyclocross and gravel tires, particularly now that we are seeing road/gravel-specific carbon tubeless offerings?

For example, Stan's Valor 29er looks like a super wheelset for the money. Light, durable, tubeless, compliant yet stiff. Theoretically, there is a low psi max, but I'm not heavy and run low psi in general. Sounds like a win for fat 700c riding, right? Am I missing something? Enve M50 also falls in this category at a higher price point.

In contrast, Stan's Avion is a new road/cx/gravel specific 700c rim, but it is more expensive, heavier and presumably less compliant since it is 2x as tall. Nox A36D is similar.

For strictly cx and gravel 700c applications, is there any reason to favor one type over the other?

With a hookless rim, how does this play out with 33-40mm tires and their psi?

[ofcounsel]

Here's what NOX Composite's says about whether running the Nox Composites A36D rim versus their lighter Skyline 29 XC mtb rim...

"We often get the question, "which rim should I run for cyclocross, the Skyline 29 or the A36D"? The comparison below will help you make a decision:
The A36D is approved for higher pressures up to 120psi, should you ever want to run the rims on the road, go with the A36D.
The A36D is narrower (20.5mm ID), and will therefore work better with some CX tires in the 30-45mm range. These tires may have problems mounting to the wider Skyline rims.
The A36D has a much more aerodynamic profile.
The A36D is a stiffer rim, mostly due to the additional material necessary to support higher pressures and the deeper profile.
The A36D is stocked in 24h and 28h drills, the Skyline is available in 32h and 28h."

Most of the same would same would likely apply when considering the Stan's Valor rims versus the Stan's Avion rims.

I thought long about this issue as well..... I'm going with the Nox A36D because I'm using my wheels mostly on paved road with only some gravel/fire roads.

Stan's Valor wheels are a bit over 21mm wide ID. I think if you're running 33mm+ wide tires and don't plan on running them at like 65+ psi, you might be ok running the valor rims over something like the Avion's.

[sandyrs]

Valors are fine for cx. Turner has them as an upgrade on their cross bike.

[sparky33]

Valors are fine for cx. Turner has them as an upgrade on their cross bike.


http://dntimmerman.blogspot.com/2015/09/tubeless.html?m=1

Dan Timmerman uses Valors for elite cx racing, but I hesitate to draw conclusions from that since I am not at all elite in my use of the equipment. Though seeing the Turner bikes upgrade is a good data point.

[sparky33]

Here's what NOX Composite's says about whether running the Nox Composites A36D rim versus their lighter Skyline 29 XC mtb rim...

"We often get the question, "which rim should I run for cyclocross, the Skyline 29 or the A36D"? The comparison below will help you make a decision:
The A36D is approved for higher pressures up to 120psi, should you ever want to run the rims on the road, go with the A36D.
The A36D is narrower (20.5mm ID), and will therefore work better with some CX tires in the 30-45mm range. These tires may have problems mounting to the wider Skyline rims.
The A36D has a much more aerodynamic profile.
The A36D is a stiffer rim, mostly due to the additional material necessary to support higher pressures and the deeper profile.
The A36D is stocked in 24h and 28h drills, the Skyline is available in 32h and 28h."

Most of the same would same would likely apply when considering the Stan's Valor rims versus the Stan's Avion rims.

I thought long about this issue as well..... I'm going with the Nox A36D because I'm using my wheels mostly on paved road with only some gravel/fire roads.

Stan's Valor wheels are a bit over 21mm wide ID. I think if you're running 33mm+ wide tires and don't plan on running them at like 65+ psi, you might be ok running the valor rims over something like the Avion's.


I read that same Nox bit too, and my take away on this whole question is that the problem the road/gravel 700c carbon rim is solving over the 29er rim is a bit of aero and a lot of psi for skinny road tires. I could be off the mark though.

[ofcounsel]

I read that same Nox bit too, and my take away on this whole question is that the problem the road/gravel 700c carbon rim is solving over the 29er rim is a bit of aero and a lot of psi for skinny road tires. I could be off the mark though.

No, I think you're on the mark. If you're running 33-40mm tires and you're running 45psi, youre gonna be fine with Valors, it seems to me. They're significantly lighter.

Me I'm running 28mm road tires at 75 psi mostly (I'm 235 lbs). The Avions or the A36D's make more sense for me.

[joosttx]

I have Enve M50s on my gravel bike. Performance is much better than my former wheels, Belgium HED. I typically ride Specialized trigger pros 33 tubeless. And pump them up between 50 - 55 PSI without any issue.... Yet.

[sparky33]

Me I'm running 28mm road tires at 75 psi mostly (I'm 235 lbs). The Avions or the A36D's make more sense for me.


28s on the A36Ds sounds fun. What is the rest of the bike?