howaboutme

Curious how the tire is secured on the hookless?

base2 

The bead doesn't stretch. Well, it will, but by some imperceptible insignificant amount. Once is is forced onto the shelves, there isn't enough slack to allow any movement towards the rim edge. Old Skool BMX rims (SkyWays, etc...) needed careful incremental inflation and several steps of readjusting the way the tire sat because the shelf idea hadn't been invented yet and with the support of a tube it was a non-issue. Now that we don't use tubes another solution had to be found. That solution was the shelf keeping the tire mechanically centered.

Kontact 

There aren't any. Specialized had a line of wheels that looked like they were tubeless (and were probably designed to be), but they weren't approved for tubeless. Why? Either they weren't strong enough for the violence of seating the bead, or they found that the bead crept.

What's going to happen is that enough people are going to convince you that the rim should be tubeless compatible, and then you're going to decide that means it is tubeless compatible. But it isn't really unless the manufacturer says it is, because it may have a small design problem like Specialized had that could end up with your wheel coming apart at high speed.

Tubeless started as a way to adapt alloy MTB rims, but those were super low pressure. Treating a questionable road rim as tubeless is like making your own brake cables.

NVFlinch 

Sure, go ahead and set 'em up tubeless. What are visiting hours at your hospital? Be sure to write your next of kin contact info on your forearm in black magic marker.

base2 

There is a lot of unnecessary doom prognostication going on here. The OP already confirmed the rim in question was the middle option of the 3 shown in the picture above. The odds of brand "x" rim in question being specifically tubeless compatible are 50/50. The odds of a successful set up are probably pretty good. Nothing a few extra precautionary layers of rim tape wouldn't build up to the shelf to interlock with the bead.

Because tubeless actually has greater hoop stress than tubes it is probably wise to use no more pressure than absolutely necessary per the various tire pressure calculators and maybe reserve it for the rear.

It might be worth thoroughly inspecting the rim for provenance and checking with the manufacturer if available. Maybe taking actual real measurements to compare against a known known. Then make calculated risk from there.

Does anyone remember when "ghetto tubeless" was a thing? This is surely better than that.

Kontact 

What is the calculated risk/reward?

On the one hand, I might be crippled or killed, but I may get fewer small punctures?

Totally worth it.

NVFlinch 

Not to flog a dog, but look at your assumptions, after all this is a guy's life were talking about. "Odds are...50/50...Odds probably pretty good"

Let's do the math:
Cost of certified tubeless rims ~ $300 (generic carbon rims)
*** Versus (pick one or many)***
Ambulance ride ~$2500 (and hey, $30 per mile from scene to hospital, ask me how I know that! And no, not from tire problem.)
Emergency room and all tests ~$5000
Each hospital room day + tests+meds ~$7000
Cheap funeral with plot $15,000 (No, no, no - I'm still here!)

Fortunately, the 'odds' are pretty good, but even that is only 50/50? Use the parachute riggers' motto, "Be certain, ALWAYS"

OP - geez, we don't want to read about you, so get some tubeless rims, OK?

choddo

I keep forgetting you guys have to pay for all that stuff

but yeah, this isn’t worth the risk on anything that’s doing any speed.

razorjack

sealing humps (not only flat area)
and sometimes a bit deeper inner groove.

Yan 

You're counting on the tire itself being tight enough so that it doesn't come off. Hookless also has a much lower max allowed tire pressure.

DaveSSS 

Great image of the different rim shapes. The ledge diameter is critical and so is minimal stretch of the tire bead that must be a tight fit. One major difference between the drawing of hookless rims is that carbon models often don't have any hump to help hold the bead. I have BTLOS and Zipp rims without any hump. Both have straight ledge/shelf areas.

I would like to find the tire bead diameter recommended by ETRTO, compared to the rim ledge diameter to determine if it's an interference fit with minimum rim diameter and maximum tire bead diameter. I used early model Michelin tubeless tires that were not hookless approved. The beads eventually stretched so much that letting air out caused an immediate release of the bead, so reinflation with a floor pump wasn't possible, but they still never came off at 55 psi and 50+ mph.