Senior Ryder 00 

Hi folks,

Just curious, are special rims required for a tubeless setup or will thenproper tape work with tubeless tires, bolt-in stem and sealant? I have several vintage bikes that I would like to switch to tubeless, but really don’t want to redo the wheels.

Thanks & regards,

Van

Barry2 

True tubeless rims are "hooked" in order to retain the tire.
Clinchers don't require that same hook.

Ghetto tubeless setups, well......... it's up to you.

Barry

unterhausen

I wouldn't do it. There are significant differences between older rims and tubeless rims. The most important one from a safety perspective is probably the bead retention lip.

People have done it, that's how Stan's got their start since there weren't any tubeless rims.

masi61

Could you post a picture showing the retention hook that you are referring to? I have tubeless ready DT Swiss R460 rims and I don't believe they are have "hooks". What they do have though is a clearly defined "shelf" that has a specific square geometry to the outer part of the interior of the rim. To me this works with the square bead of a full tubeless tire to promote an airtight seal.

unterhausen

I think I have some DT road rims in both tubeless and not tubeless versions. The hook that's important is at the edge of the shelf near the center channel. My newer rims have it, the older one I have doesn't
I think the older rim would work fine tubeless for the most part, but losing air could be a lot more rapid. I have it taped for tubeless, and it's a rear wheel, so maybe I will run it tubeless.

Seems like companies are making "hookless" rims again. I don't really pay attention to that sort of thing. In this diagram, the part that stops rapid air loss is the "hump"

Senior Ryder 00 

Thanks for the feedback.
I forgot to mention that all these wheels have hook bead rim, just not “tubeless ready”.
Cheers,
Van

Barry2 

Be aware, clinchers do have a tire retaining smooth cornered bump around the edge of the rim.
This not to be confused with the more square cornered hook on a tubeless ready rim.

Barry

cxwrench

Wrong. Almost all normal clincher rims have a hook. What they don't have is the little lip on the edge of the shelf that the tubeless tire pops over when it seats. See the diagram that someone else posted. There are more hookless tubeless rims than hookless clinchers. That's why nearly every clincher tire says something like: 'For use on hooked rims only'.

Barry2 

Try some, you’ll like it!

cxwrench

What, are you such a sensitive guy you can't deal w/ being corrected? How was my post not tactful? Because I use the word 'wrong'?

masi61

thanks for posting this. Do we know which specific rim extrusion we are looking at? Could it be a HED Belgium?
I purchased a couple extra DT Swiss R460's since they were super cheap during pre-covid times. I may have a close up look when I get home using my magnifier.

ThermionicScott 

What rims do you have? There are enough stories of trouble here with wheels that are tubeless-compatible that I no interest in trying it with regular rims. Most new rims are tubeless-compatible, so that problem is working itself out anyway...

unterhausen

I think it's just a generic diagram. Apparently some tubeless rims have wider humps, but the ones on the DT rims I have are this size or smaller. They do keep the bead from dropping into the center channel fairly effectively though.

Senior Ryder 00 

First, I’d like to do the 29er disc wheels on my townie. Hubs are labeled Marin, no labels on the rims. I got them used at our local co-op. Next, I’d like to do the rims on my 2013 Ridley CX with Alex rims.
Cheers,
Van

ThermionicScott 

What I'm getting at is that some rim models may be more able to do tubeless than others. Without any useful information, it's hard to advise either way.

tFUnK

If you're going ghetto tubeless, one factor is intended use. Will this be for road or mountain? Ghetto tubeless works better on mountain (or just low psi applications). For road or high psi use, better to get rims and tires that are marked tubeless ready.

adamrice 

I'll add my voice to those advising against doing this, at least for road riding. I've read a horror story about a guy who was using tubeless tires on tubeless rims, but the tires were slightly wider than the rim maker specified for that rim, and had a catastrophic loss of pressure (and ambulance ride). Basically road tubeless is finicky enough that I would not mess around with an experimental or out-of-spec setup.

Tubeless tires interface with the rim differently than regular clinchers. Clinchers are retained by the hooks at the tops of the sidewalls. Tubeless tires are supposed to be snug against the rim bed, and those "humps" (as shown in underhausen's diagram) hold the beads in place so they can't squirm inward and burp out air. But there's even some debate within the industry about this: There are some tubeless rims that are hookless (operating on the assumption that if the tire is properly snug against the bed, the hook is redundant—this simplifies carbon rim fabrication and supposedly gives the tire a more aero profile on the rim)—I believe Zipp's current tubeless rims are hookless. But there are some tubeless tires (eg Continental) that say they require hooks (which may simply be a CYA belts-and-suspenders policy).

oldbobcat

It's got something to do with the shape of the hook. Since they don't have spoke holes, I tried setting the bead on my Mavic Ksyrium SLs tubless. Big fail. Glad I found out before using sealant.

cxwrench

If it's the shape of the hook can you explain how hookless tubeless rims manage to work? I'll wait.

oldbobcat

You win. I just looked up hookless tubeless rims. I didn't know there was such an animal. Got any more?

Eric F 

I recently converted the 26" Mavic X517 rims on my 20 year old MTB to tubeless, using the recipe recommended in a YouTube video. Old rim tape was removed, the inside of the rim was thoroughly cleaned, and wiped down with alcohol. Rim was sealed with 1 layer of electrical tape, plus 2 layers of Stan's tape. Tires mounted fairly easily, and inflated just fine with a standard floor pump.

I have had 1 flat where the tire burped on fairly hard impact after a stair-step drop-off. I was unable to get the tire to reseal on the trail (probably needed more sealant), and finished my ride with a tube. Being that I'm on an old bike with rim brakes, I suspect the rim may have gotten warm to the point of softening the sealant at the tire bead on a long and steep descent section, and the impact was just too much for it.

Other than that one issue, they've worked just fine for me, and are getting used about twice a week.

I'm not sure I would try this with old road rims.

ThermionicScott 

Mavic X517 looks like it was a good candidate. Mavics are often a tight fit, and that rim has a nice flat shelf for the beads with a well in the middle.

cxwrench

Any more what? Things I know about and you don't? Given enough time I could probably come up with a couple hundred. You learn about a lot of things after almost 30 years of doing it for a living.