
Jim’s Tech Talk
By Jim Langley
Last week, I introduced you to my neighbor Jessica and her “mystery” flat tires issue. It turned out that the culprit was a too-narrow rim strip in a tubeless-ready rim. Here’s where you can catch up if you missed the story: “Mystery” Flats in Tubed Tubeless-Ready Wheels. Be sure to read the great reader comments because there are many helpful tips.
Today, I want to get back to a few folks who asked some interesting questions and made some good points. I’m starting with “Bike Fitness Coaching,” who wrote:
“Jim, So that we are all on the same page, please define (and the difference between) Tubeless and Tubeless-Ready. And while you are at it, Clincher and Tubular.”
Before I could reply, another reader, “Karl,” wrote up some definitions (thanks, Karl!)
I have edited Karl’s answer a little below and added photos.
But, first if you want to hop in the RBR time machine, you can go back and read the first ever review of Shimano and Hutchinson’s joint-effort, which was called Road Tubeless. Yes, we covered it here first on RoadBikeRider circa 2003: https://www.roadbikerider.com/shimano-dura-ace-7801-sl-wheelset-d1/.
Now for some definitions…
Tires
Categories
Clincher tire: Tire with beads that hold it onto a Clincher rim that has sides that hold the tire in place (see Clincher rim below). Standard tires (non Tubeless or non Tubeless-ready), Tubeless and Tubeless-ready tires are all types of Clincher tires.
Tubular tire (also called a Sew-Up): Tire with a round construction, like a giant skinny donut. There are no “clincher” tire beads to hold it on the rim. Tubular tires usually have a tube inside and the tire casing is sewed (sometimes glued) together around the tube. There are tubular tires without tubes inside made by Tufo. Tubular tires are only compatible with tubular rims and they’re held on with adhesives such as glue or tape.
Tubeless tire types
Tubeless tires: These have a butyl inner liner inside the tire so they do not leak air and do not require sealant. It may help to think of bicycle tubeless tires as similar to most modern automotive tires. They too remain airtight without any sealant.
Tubeless-ready tires: Also a tubeless tire, but without the butyl inner liner and because of that sealant is required.
Note that some Tubeless and Tubeless-ready models have bead locking technology to help seal the tire on the rim.
Rims
Categories
Clincher rim: Standard, Tubeless and Tubeless-ready are all types of Clincher rims. Think of the word Clincher and part of it (“clinch”) describes how the two sides of Clincher rims that have a U-profile give Clincher tires something to hold on to. The rim “clinches” the tire in place.
Tubular rim (also called “Sew-Up rim”): For Tubular (Sew-Up) tires only. These are box section rims with a flat concave surface that Tubular tires are adhered to with glue or tape.


Tubeless rim types
Tubeless rim: There are no spoke holes in the rim or the spoke holes are permanently or semi-permanently sealed so as not to need sealing with tape or a rim strip. Tubeless rims accept Tubeless tires and sealant is not necessary. You can use it if you want, but a Tubeless rim and tire will seal and work fine without sealant. That’s one of its advantages. Not using sealant saves weight and means no sealant hassles should you flat on the road and need to install a tube.

Tubeless-ready rim: There are spoke holes, which are sealed with special tapes or rim strips so that the air and sealant cannot leak out.
Note that some Tubeless and Tubeless-ready models have bead locking technology to help seal the tire on the rim.
These definitions are confusing so I provided some photos that I hope help explain.

Cutting to width Gorilla tape
Next up is “Doug’s comment.
“I’ve built and rebuilt several bikes, and still find your advice very useful. A question regarding Gorilla tape: how did you cut it down to exactly 23mm, particularly since as you write, the tape or strip width must be exact?”
Thanks for the kind words, Doug. Please see the photo. In it, I’m cutting a wide roll of Gorilla tape to 24mm wide. I measured a few things around my home shop and found that a roll of painters’ tape was exactly 24mm wide. I then put a utility knife blade on top and clamped it in place. With the blade held at the right height, it’s a relatively simple job to turn the wide roll of tape while pressing against the blade to cut the tape to the exact width needed. Of course, you’ll need to find the right width block to place the blade on.

If you happen to have 25mm wide rims, you can buy rolls of Gorilla tape in that width to save the cutting down. Here’s a link: https://amzn.to/32f26lZ.

Skip the rim strip or tape altogether
We’ll let “David” take the last pull. He commented, “I started using Veloplugs a few years ago instead of rim tape. It seems you then don’t have to worry about the rim strip creeping and it helps to make it easier to mount tires. Do you have an opinion about the use of Veloplugs?”
Thanks, David. Here’s a link to Veloplugs and a photo: https://www.velocityusa.com/product/accessories/veloplugs. I am a big fan of Veloplugs and reviewed them when they first came out. The one thing is that they don’t fit all spoke holes so you want to check that before buying them. If they fit, they reduce the effective inside diameter of the rim (since there’s no rim strip), which as you pointed out, makes it easier to install and remove tires.
Veloplugs are made for tubed tires, not tubeless. They don’t seal the holes so air and sealant can leak out through them. They should weigh less than most rim strips, too.
Thanks for all the great comments readers!
Ride total: 9,737
One issue that caused me to give up on Velo plugs years ago is that — in my case, with the particular wheel set — they would let water sneak into the rim through the spoke holes during rain rides. I would have to take off the tire and tube and work to drain out the water (during one memorable rain-soaked event, it seemed like several ounces!).
I switched back to tape on those and all my other wheels.
7801-SL one of the best wheels even made. We tested the wheels and between 2 of us, we HAMMERED on them. Never broke a spoke, only re-trued once and got 49,000 miles before they started severely cupping.
Here’s one for Jim, you talk of tubeless and tubeless-ready wheels, what are tubeless and tubeless-ready tires? Differences? Can you you only use tubeless tires on tubeless wheels and tubeless-ready tires on tubeless-ready wheels?
Hi Rick,
I explained the difference between tubeless and tubeless-ready tires in the story as follows. Below in another comment, I added a few more thoughts. But, here’s what I said in the story:
Tubeless tire types
Tubeless tires: These have a butyl inner liner inside the tire so they do not leak air and do not require sealant. It may help to think of bicycle tubeless tires as similar to most modern automotive tires. They too remain airtight without any sealant.
Tubeless-ready tires: Also a tubeless tire, but without the butyl inner liner and because of that sealant is required.
Note that some Tubeless and Tubeless-ready models have bead locking technology to help seal the tire on the rim.
Then, in answer to your second question, I recommend following the rim (wheel) and tire manufacturers’ compatibility requirements. In the early days of tubeless many people put regular clincher road tires on different types of rims trying to make things tubeless that weren’t designed to be tubeless. The result was rolled off tires and some bad crashes.
So, I stick with what the wheels and tires are designed for and if I’m not sure, I do the research contacting the makers to determine for sure that what I want to do is going to be safe to ride on. I know that’s not very specific, but it’s easy to get confused by the different terminology in wheels and tires. So, getting the facts and making certain the wheels, tires and setup are all right is very important.
Thanks for the question,
Jim
Jim, the tubeless rim that you show appears to be well used, looking at the valve hole. The hole appears corroded and no longer round. Was the metal corroded by the sealant?
Thanks for the question, Bill. That rim is a Shimano rim – the one from the original review I wrote here back around 2003. So, it’s old and well used both as tubeless un sealed and sealed. And with different types of sealants.
There is corrosion in the rim and it’s likely from the sealant. Some types supposedly contain ammonia (sealant makers say it doesn’t, but others say it does). Ammonia attacks anodized aluminum.
I had to stop using these rims as tubeless because I couldn’t get the valve area to seal any more. They still work great as tubed wheels. I had many great rides and a few podium finished on these hoops so they served me well for many miles even with the issues.
Great question. Thank you,
Jim
Would like to see what the butyl inner liner looks like in the Tubeless and Tubeless applications.
Thanks for the question, Paul. I’ve looked at a lot of the tubeless and tubeless-ready tires inside and out and to me, they look the same as the insides of any tire. A tire manufacturer could probably point out the difference.
But, mostly the way you know is that the genuine tubeless tires are heavier. The way Hutchinson described it was extra layers inside to seal the pores in the casing. They add weight. Also, the tires are stiffer when you handle them.
Maybe if I cut apart some different tires I could discern a difference. If I get to to do that, I will write about it.
Thanks again,
Jim
I have found that gorilla tape is air permeable. I stopped using it and now use tubeless tape.