Converting to tubeless question
 

I have UST tubeless wheels and tires and will be converting from tubes to tubeless. Internal rim width is 19mm and seeing conflicting info as to whether I should use 21 or 25mm rim tape? Also...should there be one layer of rim tape or 2?

If it is a UST rim, isn't the rim bed free of holes? A feature of UST is that it is supposed to be able to seal without tape. If this is not the case, depending on the tape used, one turn with about 4-6" overlap should suffice. To account for the channel in the center of the rim bed, your tape needs to be 2-3mm wider than the internal width, in order to ensure the tape is wide enough to touch both sides of the rim while also conforming the contours of the center channel.

Just curiosity, but why does tape need to be that wide and/or be done at different widths for different rims? That is, why can't tape just be the same width for any TL rim width, presuming spoke hole diameters are pretty uniform, plus some extra as a safety margin. For argument's sake, why can't a 15-18mm width tape be used for any TL rim?

The tape serves two purposes, as was explained to me a few years ago. Assuming the rim bed is drilled (as nearly all are), it needs to cover the spoke holes and, secondarily, promote a good seal between the tire and rim. To do that second part it needs to go right up to the edge of the rim bed. You may actually see some folks here talk about "building up" the rim bed to get a better seal.

That said, I have a set of rims that are not UST, but also do not have a drilled rim bed, and they are not taped, and they hold air just fine.

Good question! I’ve never really considered it; all my wheels came full-width factory taped, and I just replicated the tape width when replacement has been needed. If I had to guess, I’d say that going full width tape avoids issues where the tape might terminate awkwardly and not lay flat, like at the crest of the bead lock hump, and be prone to failure. Similarly, if the bead is sitting on the tape, it’s less prone to pull at the tape when the tire is removed.

Try it and get back to us.

Thanks. Yeah, I've seen reference to rim bed sealing being a reason, but as you mentioned, there are rims that are hole-less where somehow this isn't a factor, which brings into question the necessity of tape extending up by the hooks (eg. UST, Fulcrum/Campy 2-way, and eg. Lightbicycle who provides hole-less as an option when ordering).

Which UST rims do you have? I have Ksyrium Pro UST's and tape is not needed. If you do need tape 4mm wider than ID and doing a double wrap is what I do.

That's how I got mine without holes...and they hold air beautifully

Cool. Would there then be reason to think if you had ordered the same wheels instead drilled with holes, you'd need to use tape wider than the center channel? I wonder if LB adjusts the hook/shelf distance or something when going undrilled, though that seems unlikely.

Yes. In addition to what I stated above, chaadster makes the point that if the tape doesn't go all the way to the edge of the rim bed, there will be an exposed tape edge that could work it's way up causing the system to not properly hold air. As I said, I don't know the exact reason that we tape edge to edge, just that I was told by someone who was pretty good at it already a few year ago that it's the proper way to prepare the rim, and I've never seen anything that contradicts that (when taping is required).

Cosmic Pro Carbon SL from a year or two ago. They arrive today and I know are setup with tubes, so assuming (maybe incorrectly) that they won't have rim tape..or that I should probably replace.

Related question. I have an old set of shamal 2-way-fits that I have always run with tubes. What would it take all-in to convert these to tubeless? Tires, valves, sealant, is that it?

That'd be all that you need, but I'd also recommend a sealant syringe (10-12 bucks on Amazon), which will allow you to add/remove sealant through the valve, which makes set-up and maintenance much easier and cleaner. Unfortunately, some valves don't have the ID to pass the syringe tube, so you might need to do a little research on that point before buying valves. I use the aluminum Muc-Off valves, which will pass the tube, if you don't want to be bothered with the leg-work of other options.

Maybe start here?

I also have an older set of Campagnolo Shamal 2Way fit wheels that I have always run tubeless. They already had the valves installed when I bought them brand new. The Hutchinson Fusion 5 tires I am using will hold air without sealant and I often don't bother using any. Right now, I have sealant in one tire and none in the other. I can't even remember which one has the sealant and which one doesn't

Because air and sealant will get under the edge of the tape. If you use the proper width tape for the rim this won't happen.

Thanks WhyFi , Sy Reene & alcjphil Very helpful.

Any recommendations on specific products for tires and sealant? The user manual says to use campy valves only, which I don't have but looks like won't be that hard to source.

I'll probably set them up with 28mm tires if that makes a difference.

I'd recommend Orange Seal (regular, not Endurance or anything else) for sealant, but others have had good experiences with different sealants - just stay away from Stan's for road bike use.

In terms of tires, there's a lot of good ones out there. No need to rehash it here, but take a look through this current thread for some ideas - https://www.bikeforums.net/road-cycl...ess-tires.html

My LBS advised the same thing to me. They recommend Orange for road bikes. It' a little more expensive, but I guess It's worth it.

If you had to pick one to recommend favoring price and durability over speed. I'll still use wheels with tubes for brevets so this would just be a training tire for 2-6 hour mostly-solo rides.

Sorry, that's not exactly in my wheelhouse, so I don't have any first-hand experience. I'm tubeless because I want fast and supple and was tired of changing tubes on the side of the road every few weeks. I think that Pirelli has some decent offerings along those lines, though.

I'm curious, is the rim bed drilled or solid (no nipple holes)?

Yah... to me it’s comfort and speed with the “durability” of puncture protection that comes from being tubeless. I feel like even gator skins are going to wear out after 3000 miles so might as well get something comfy.

OK. Relax the price/durability preference. What tire would you recommend for someone who rides long distance and is looking to convert one of many wheelsets to tubeless to give it a try for the first time? I normally use cheap tires for training miles, but I can treat myself for this experiment.