The tubeless transition: How big of a mess is involved?

Previously I wrote a short introduction to tubeless tires, and how they’ve slowly made inroads into the world of road cycling after becoming dominant in the mountain bike world. Now I’m going to be putting all of it to the test. Today I’ll walk you through the process of converting to tubeless, as I did it.


Much like hydraulic disc brakes, tubeless tire technology is its own animal with its own unique needs, tools, and supplies. For the best chance of success, you will need to prepare the necessary items as much as you can.

Theoretically, both the wheelsets I use on my TCX Hyro are tubeless-ready. That said, for this job I am using only the custom H Plus Son The Hydra wheelset I got second-hand in 2020. I found quite a bit of corrosion inside the rims of the stock Giant S-X2 wheelset, so I’m repurposing that as an indoor training set instead.

The other items and sundries required for tubeless, I slowly collected over months and years. The very first ones were the 35 mm tubeless Presta valves and tubeless rim tape, both from tubeless tech pioneer Stan’s NoTubes. Next was a big bottle of Orange Seal’s Endurance tire sealant – a favorite of many gravel and MTB riders – and KOM Cycling’s sealant injector kit, which includes my second valve core tool. I also availed of their tubeless tire repair kit for on-the-road repairs.

Last of these were tires from an unexpected name: American Classic. The brand better known for seatposts, hubs, and wheelsets closed up shop in the mid-2010s, but was resurrected under new management and specializes in an entirely new product category…for now. As most of my riding happens on the road, and I like tan sidewalls, I got their Timekeeper tubeless-ready tires in the 700C x 28 mm size. The most striking thing about them, and the brand’s tire offerings in general, is the price. At $35 apiece, sold direct by Amazon, these are half the price of their rivals.

If I was going to fool around with road tubeless, I might as well keep the point of entry as painless as possible, at least in price. The Timekeepers were practically begging me to try the technology with them. I am very interested in how they hold up against Continental’s Grand Prix rubbers, a long-time favorite of mine.

The final piece of the puzzle was a way of seating tire bead against wheel rim. The best way of doing this is with an air compressor, but I didn’t have one at hand, and decided to go the route of the fancy charge-chambered floor pump.

My weapon of choice is the Bontrager TLR Flash Charger 2.0. A refined version of the popular original, the Flash Charger’s charge chamber can be pumped up to 160 psi, which can then be let loose in one huge slug of air to blow tubeless tire beads outwards to seal into compatible wheel rims with the signature “pop” of success. Yet another piece of experimental tech for me.


Most tubeless-ready wheelsets, and those that are built custom like mine, still have spoke holes drilled into the rim bed for inserting spokes and nipples into them for wheel building, spoke replacement, and truing purposes. For a tubeless application, these have to be made airtight, and this is where the tubeless tape comes in.

I stripped out any old non-tubeless rim tape (any cloth tape from Zefal or Velox has to go), then cleaned the rim bed with rubbing alcohol and a shop towel. Then, starting from a slight overlap with the valve hole, I started laying down my tubeless rim tape, making sure to keep it taut and adhered to the rim bed with as minimal bubbling as possible by running my thumb over it. As I plan to run more than 45 psi, I laid down at least two layers of rim tape as per Stan’s instructions, ending at the valve hole with another bit of overlap. I then pierced the tape at the valve hole for fitting the tubeless Presta valve in.


Next, I fit the tire to the wheel, much the same way as I would a tube-type clincher. One bead first, then the other.

On the Hydra rims at least, the Timekeeper tires went on pretty easily and with little struggle. I remember Continental and Panaracer tube-type clinchers being much tighter and harder to fit when new. These went on practically tool-free.

Hard to tell from this photo, but unseated and with no air, the tires are a baggy fit.
Note the rim-to-tire-bead gap around the valve stem.

You’ll note that, without an inner tube in place to push the tire beads out, these tires will be a rather baggy fit on the rim bed. That’s just for now.


This step is where American Classic’s instructions step in and become slightly out of sequence compared to how many people do it. The company recommends you put in some sealant first before trying to seat the tire beads.

Giving in to more popular methods, I tried dry-seating the tires first without any sealant. It didn’t work. Three times I inflated the Flash Charger to 160 psi, and three releases later, exactly zero tire seating happened. This was when I decided to follow the instructions, plus add another step.

Speaking of sealant, American Classic has to be applauded for citing a recommended amount of it per tire. For my 28 mm tire application, it told me to bring in 35 mL of goop. I made it a round 40 mL of Orange Seal Endurance, since I’ve found more is usually better for the initial mounting. At least the company isn’t leaving you to your own devices and making you guess, like many others do.

Remove the valve core and inject the sealant into the valve, then slowly roll the tire to distribute the sealant. Stop after two rotations.


The optional added step is to sponge some soapy water onto the tire bead and wheel rim. This allegedly acts like a lubricant, assisting and encouraging tire bead and wheel rim to meet, making sure the tire bead doesn’t catch on anything before that point when your slug of air enters the rim. It’s repeated very frequently as constructive feedback for when tubeless tire installs go wrong.


With everything in place, it’s time for the Flash Charger to come into the picture. With the left switch set to “Charge” and the bigger right switch flipped down to “Fill Tank,” I pressurize the charge chamber to 150-160 psi. Watching the digital gauge as I go, each full stroke adds about 3-4 psi. There’s quite a bit of resistance as you start getting to 130 psi and push to the limit, though. Fine on your first go-around, but after a half-dozen attempts, the unexpected upper-body workout can get pretty tiring.

Hooking up the pump chuck to the wheel, which is kind of hard on a 35 mm tubeless Presta valve just because it’s so short, I flip the switch from “Fill Tank” to “Release Pressure” and make sure the pump chuck is firmly against the wide-open valve stem. Removing the valve core increases the chances of the tire bead sealing against the wheel rim and yielding those satisfyingly loud dull pops, as there is less obstruction in air flow. In this case, you’ll also know you were successful when the pump chuck itself requires hand pressure to stay in place against the valve stem as it tries to blow itself off.

As you remove the pump chuck, jam one of your fingers against the open valve. Ready your valve core in the other hand. From here, it’s a matter of quickly inserting the valve core and twisting it into place before enough air escapes from the tire…undoing your hard work. Congratulations!


After successful mounting, you’ll want to clean up the mess you made, especially if you spilled or lost some sealant in the process. The latex in tubeless tire sealant is sticky and can attract dirt to it; you don’t want it on your rug or carpet. It will wash off a tiled floor easily enough.

Inflate the mounted tire to a pressure close to the maximum, then spin the wheel and shake it vigorously to get the sealant inside the tire distributed all over. Wobbling the wheel while holding it sideways seems to be the preferred technique for this.

If you’ve got time to spare, leave the wheel and tire overnight. Take note of the air pressure and check it the next day if it retains its sealing and successfully holds air over a prolonged period. Once it does, you can now deflate the tire to your desired riding pressure.

Did I run into failures? Sure I did.

I had to build up more layers of tubeless tape than I initially thought. Fine if you’re still playing around with a dry seating job, but once sealant has been injected into the tire, it’s a right old mess. Attempting to suck the sealant up with the injector doesn’t get all of it either. The photos just don’t show it. If you’re doing this the first time, buy more tubeless rim tape than you think you need, and get the right width for your rims.

When I bought the tubeless Presta valves many years ago it was purely on a whim. Just in case, I said. Well, I wish I could travel back in time and tell myself, “buy something else; they’re too damn short.” These 35 mm valves are for mountain bikes at best. Using them on a road bike or gravel bike wheel, you risk the pump’s valve chuck not having sufficient purchase. Get longer tubeless valves, at least 40 or 45 mm long, and maybe get some spare Presta valve cores too because they will clog up with sealant over time.

The important thing though is that this (tiring) job was a success after roughly three hours. In the next installment I’ll go out for a ride and give my initial impressions of these tires.


2 thoughts on “The tubeless transition: How big of a mess is involved?

  1. Seems to have gone quite well! Interesting point about the valve core, I always struggled with it – with the core in, the tyre just wouldn’t seat, but with the core out, there was the faff about losing pressure. I think Topeak launched a new charger pump recently which includes a core removal component, but your approach seems worth a go!


    1. I can’t take credit for it; it was something I picked up from JOM aka Gravel Cyclist in his review video of the original Bontrager TLR Flash Charger.

      I tried looking for that Topeak pump (JoeBlow Tubi 2-stage, I believe it was called) but never saw it on sale anywhere, so I went with the Flash Charger 2.0.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.