Technical FAQ: Mavic tubeless tires, 12-speed chain on 11-speed group

Have a question for Lennard? Please email him at veloqna@comcast.net to be included in Technical FAQ.

Dear Lennard,
I have a set of Mavic Ksyrium Pro Carbon SL tubeless wheels that are a couple years old now. They came installed with Mavic branded Yksion Pro UST II tires. Mavic recommended that only their UST tires be used with those wheels, hinting it might be unsafe to use other brand tires due to compatibility issues. However, Mavic appears to be out of the tire business now, and it is next to impossible to find Mavic UST tires anywhere. Can I use another brand of tubeless tires on Mavic UST wheels? Or am I doomed to buying another set of wheels?
— Steve

Dear Steve,
That’s a great question that many Mavic customers may be wondering about. The short answer is, no, you are not doomed to buying more wheels, and, yes, you can use other brands of tubeless tires on those wheels. I have attached the graphic about rim and tire compatibility and changes to Mavic’s rim bed from 2020 to 2021 models.

Below are answers from two Mavic staff members to your question.
― Lennard

From Mavic’s Road Category Manager:
When we 1st launched our UST Tubeless wheels for Road use back in 2017, we developed the wheel and the tire together.

Since at that time there were no official norms / standards for road tubeless (nothing in ISO or ETRTO), we could only guarantee ease of use and safety for the combo Mavic wheels + tire. Which did not mean that this was the one and only safe and ease to use setup, but we could not guarantee that any other setup will work right.

Since then, the UST wheel dimension has been accepted by the industry as the official norm for road tubeless and is now part of ETRTO and ISO. For a couple of years now, many tire manufacturers (Schwalbe, Vittoria, Pirelli, Zipp, Hutchinson, Michelin, etc.) have been able to rework their bead diameter and stretch according to this standard and many wheel brands are now also complying with this set of rim dimensions as well.

The wheels that your reader is using do comply with this standard, so any tire produced in the last 2 years by one of the above-mentioned tire brands will work safely. Those tires should mention somewhere (sidewall, packaging) the ETRTO and/or ISO compliance.

That said, Mavic is not totally out of the tire business. We are keeping in the line the Yksion Pro UST tire (25 and 28mm), precisely for our customers who have been early adopters of our UST wheel and tire system.

I’m aware that they might not be easy to find at the moment in the USA, but we’re actively working on rebuilding our distribution and service network in the USA.
— Maxime Brunand, Mavic road category manager

From Mavic’s global PR manager:
No worries to buy any other tire brand. We NEVER said to only use Mavic ones; this is the best combination but not a compulsory mount.
He can buy either a TL (tubeless) compatible one, as brands are now supposed to comply with the ISO international norm (ISO4210-4775/ETRTO), if Steve wants to get all the benefits from running without a tube.

Or he can also mount a [standard] tube tire tire (still no need for rim tape) as anyhow our rim diameter is following the norms.

Here is some additional info — a video of how to mount a tubeless tire, following the right tips.

Mavic’s US subsidiary shut down back in 2020 due to the under-administration period and ownership change. We’re still in the process to re-open one in the USA but facing many constraints. Nevertheless, we’ve started again to service our customers through the contact page.

We apologize for this situation that is not reflecting our will to provide correct support.
— Michel Léthenet

Dear Lennard,
Your questioner asks about steel frame industry standards and suggests he will “probably” be ordering Reynolds 953 tubed frame.

Though I prefer Columbus for my stainless builds the Reynolds 953 is also stainless steel thus holes for internal transmission would not provide opportunities for corrosion. This point seems to be missed in your answer to the query.

Thanks for your years of maintenance documentation, as I provide some of my customers with a copy so they can at least begin to maintain their new bikes and understand the nuances of Bike Maintenance.
— Michael P O’Brien, obriencycles

Dear Michael,
Thanks for pointing that out. Indeed, if he does choose Reynolds 953 stainless steel for his frame, his concerns about corrosion would be moot.
― Lennard

Dear Lennard,
I noticed that Shimano is going to use the existing XTR 12-speed chain for the new Dura-Ace and Ultegra. Would this chain work with the 11-speed systems? I’m hoping Shimano will continue to offer the Dura-Ace 11-speed chain for a while yet.

Also very disappointed that they didn’t at least offer Ultegra in a mechanical version; they’ve basically priced an Ultegra spec’d bike far out of my price range, and I challenge anyone to try and tell me that electronic offers any increase in performance over the mechanical version.
— Steve

Dear Steve,
It makes no sense to use a 12-speed chain on an 11-speed group when there are plenty of 11-speed chains available. Even if Shimano were to stop making 11-speed chains (which I doubt will happen for a very long time), there are lots of other manufacturers making 11-speed chains that work just fine with Shimano drivetrains.
― Lennard

Dear Lennard,
I’m building a gravel bike. Can I use sram red compact 50/34 and GXP Di2 front derailleur? I would be using everything Shimano GXP Di2 except for the crankset. I saw the max teeth for the front derailleur is like 48 or 46 according to the Shimano webpage. I also saw Dylan Johnson running a 52/36 with GXP Di2. I have no idea how he worked that out. Do I need to measure something like chainline or q factor? From my understanding, the Q-factor is 150mm on SRAM crank and the GXP would measure out to be 151mm.

Can you please confirm if this will work without issues?
— Jonathan

Dear Jonathan,
That crank should work fine with your drivetrain.
― Lennard

Dear Lennard,
I have a carbon road quick-release fork where the spacing measures around 104mm. It has a few chips in the paint but has never been in a crash and has no structural damage that I’m aware of. It’s from a 2014 Cannondale that I recently bought from a trustworthy seller.

Do you think it’s safe for a 110lb rider? In normal times, I’d just buy a new fork but they’re hard to come by like everything else in 2021.
— Josh

Dear Josh,
I of course cannot comment on the safety of a fork that I have not inspected. That said, if the fork is indeed in good condition, the fork flexing 2mm on each side to pull in to meet the ends of the 100mm front hub should not be a cause for concern, particularly for a 110-pound rider.
― Lennard

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Lennard Zinn, our longtime technical writer, joined VeloNews in 1987. He is also a custom frame builder (www.zinncycles.com) and purveyor of non-custom huge bikes (bikeclydesdale.com), a former U.S. national team rider, co-author of “The Haywire Heart,” and author of many bicycle books including “Zinn and the Art of Road Bike Maintenance,” “DVD, as well as “Zinn and the Art of Triathlon Bikes” and “Zinn’s Cycling Primer: Maintenance Tips and Skill Building for Cyclists.” He holds a bachelor’s in physics from Colorado College.

Follow @lennardzinn on Twitter.