After 12 years of publication, more than 10,000 stories and countless roadside adventures and Top Rides it’s still our tech reviews that get the most interest here at PEZ. Fan mail, follow up questions, photos of readers’ bikes with equipment bought after reading a review or tips followed – sometimes the PEZ inbox overflows but never so much as when we’ve run reviews on Tubeless wheelsets.
It seems that many readers out there are intrigued about the technology and love reading about it but still have seemingly a million questions to ask on the subject. To get some answers we went straight to the source, American Classic’s head designer, engineeer and a man known in the industry as just a wheel guru – Bill Shook.
The man himself, Bill Shook
Ok let’s start with the basics Bill – why tubeless?
Tubeless wheels benefits road riders for many reaons;
* Self-sealing of punctures due to the sealant used in the tubeless tires.
* Tubeless wheels have lower rolling resistance which translates into more speed. There is no friction between tire and tube because sealant replaces the tube. This reduces weight. The ride quality is smoother.
In the American Classic tubeless system, you can ride a smaller lighter tire because the tire spreads across my wide rim design. It improves the tire contact surface with the road.
Tubeless technology has been around for a while now – how long have you been working on tubeless?
And what lead you to believe that road tubeless was a solid format?
I have a great deal of experience with MTB tubeless in our American Classic line-up. MTB riders have embraced tubeless so it was only natural that I needed to bring this great technology to road bikes. For road bikes, tubeless has lower rolling resistance, lower weight and puncture resistance with sealant inside the tire.
Bill at last year’s Eurobike where his wisdom on all things tubeless was constantly being mined by media and industry types alike.
What do you feel are the better tires available currently?
At American Classic, we personally ride on our AC tubeless road bike wheels IRC Pro-Light or Schwalbe One’s. We like the way these tubeless ready tires install, they have a reasonable weight and fit well. There are other tubeless road tires on the market, but these are two we currently like. We do not recommend using tubeless tires with carbon beads for any reason as the carbon fiber beads can be damaged by bending or folding them so they may not stay on the rims securely. Carbon fiber beads are very tight and inflexible so they do not install easily. We do not recommend heavy or inflexible tires for the road because it decreases performance. Tubeless road tires are often too thick because the tire makers are still thinking they need to supply a protective layer under the tread, not necessary because you install tubeless sealant inside the tire.
As the head honcho at a wheel company Bill could ride anything he wants of course but on his personal bike at the moment it’s AM Classic’s tubeless wheels with Schwalbe tires.
The AC wheel looks like it has a “short” rim sidewall (when it’s really just that the bed sits a little higher). Does this have an advantage? And conversely is there any disadvantage?
Looks can be deceptive. Other makers on the market have even shorter sidewalls and to achieve this, their rim is a smaller diameter which can cause the tires to come off.
The advantage of the American Classic sidewall design is that the tire fits tighter and in conjunction with my bead barb design, it holds the tire bead in place. There is no disadvantage that I can think of. It works well.
Are there differences in the types of raw material (rim) that make some more suitable to tubeless?
Currently road tubeless rims are aluminum. Any rim material could be developed into tubeless ready rims if the design is correct.
What are the elements of a ‘correct’ tubeless design?
A correct rim design for tubeless must work for both standard tire tube setup and for tubeless tires. The tire must fit tight on the bead seat diameter to seal the tubeless tire. I designed in a bead barb keep the tire from burping or coming off the bead seat.
So carbon tubeless could be possible?
There will be carbon tubeless someday…
So is magnesium suitable for tubeless then?
It will take development of a non-corrosive special sealant as magnesium is damaged by ammonia.
Is there an optimal rim width now versus “wider”? (relative to air pressures and typical road tire sizes).
My design for American Classic tubeless road rims is ideal. It is 22mm wide with an inside width of 19mm and is combined with my curved bead seat design. The inside width is what is important on in road tubeless because you can use a lighter, smaller tire and it stretches to the desired tire width. For example, most road tires are 23mm wide and on an AC road tubeless rim a 23mm tire becomes 26mm wide. So the result is you have a lighter tire, and an improved tire patch meaning it hugs the road and corners great without rolling around on the rim. You can even use a 20mm wide tire and it becomes a 23mm tire great for racing use. My bead seat design is important because the tires do not burp on AC rims, a bad problem for many of our competitors’ road tubeless wheels.
I designed the first modern, wide road bike wheel on the market in 2004 called the American Classic Hurricane which was 22m wide and 19mm inside. At the time it was a revolutionary concept for road…and it was often poo-poo’ed by riders and the press back in the day who said it was a MTB wheelset since they favored narrow road rims. Now wide rims are becoming a standard and everyone is claiming it as “their idea”.
Is there a magic number for tire pressure and tire size? (based on rider weight)
Tire size and pressure are determined by several factors including rider’s weight, rough/smooth/wet/dry road conditions, desired comfort level and intended use such as racing, climbing or training. We recommend you do not go below 90 PSI/6.2 Bars to avoid burping or sudden air loss. The maximum tire pressure is 120 PSI/8.2 Bars or whatever the tire is rated for.
On our American Classic wheels, the desired combined wheel and tire qualities are achieved by stretching out the smaller tire casing on our wide rims and effectively making the tire bigger. For example a 23mm tire becomes a 25mm tire. The advantage is a smaller tire is lighter but you have the large contact surface of a wider, heavier tire. Also, smaller tires on wide rims reduce tire roll on the rims. Using a wider rim with a smaller tire minimizes float for improved handling, confidence and control.
Do you have a favorite sealant?
There are some good ones, Joe’s comes to mind foremost and Orange Seal. We use these in our personal bikes because they have fewer harsh chemicals that may attack the rim and they seal up holes from punctures well.
Will sealants eventually degrade the rim?
Some sealants say they are “eco-friendly” but they are not and contain harsh chemicals in them such as ammonia. You can smell the chemicals when you open the bottle. Some smell like ammonia window cleaner. These sealants can eat the tape adhesive and inside of the rim. American Classic seals the rim with our protective AC tubeless tape set (1 fiber layer and 2 layers of tape). The tape protects the rim.
You will need to add more sealant periodically if you get a puncture or if it dries out. You will need to clean sealant out completely and re-install new sealant approximately every 3-6 months (3 months in hot weather conditions).
Is Tire tech better now? How so?
The tubeless ready road tires are slowly improving. They have not caught up with MTB tire technology yet.
Can you run a disc wheel at different pressures given there’s no friction at the brake track / sidewall?
No. The road tubeless technology is about rim width, shape and tire interface. It is not about the disc.
What could make tubeless better?
Do tubeless road tires wear any differently given the larger surface contact?
No they do not wear faster.
Should Tubeless lose air when left stored?
Yes, same as tube tire. Thinner tires will lose air faster.
Is the AC valve design any different than others on the market?
The American Classic valve is special and works really well. The AC valve seals on the surface of the rim, not the edge of the hole because of it’s functional cup-shaped bottom contour. It uses Two “O” rings to seal tight and has a removable valve core. It is an established design for both road and mountain bikes.
Is there a Max pressure that people should be aware of with the rims?
For American Classic road wheels, our maximum recommended tire pressure is 120 PSI/ 8.3 Bars or whatever the tire is rated for. It’s the same for road tubeless or tire-tube applications.
What’s the best way to mount tubeless tires/sealant on an AC tubeless rim?
We have some great directions on our website but some tips are;
* If you have never installed tubeless ready road tires on road tubeless wheels, you need to take your time and follow directions. It is not as simple as popping in a tube until you get the hang of it.
* Our AC tubeless ready road wheels come pre-taped, required to seal the system. Our wheels come with AC tubeless valves and you need to install them next.
* You will need tubeless ready road tires without carbon fiber beads, tubeless sealant, liquid dish soap and 2 small towels.
* Mountain bikers are familiar with soaping the rims. This is how you do it. Use soap instead of tire levers to install the tires. Wet a small towel and pour a lot of liquid dish soap on the towel. Rub the towel on the rim and tire beads inside and out, all over so that it’s sudsy and slippery. Use a lot of soap and re-soap the towel as needed.
* Start installing the tire by hand opposite the valve and work the tire on moving towards the valve. The last bit of tire installs at the valve and you use the dry towel to help you pop it over at the end at the valve. Tip: if you use carbon fiber bead tires they are really tight and do not install well even with soap so do not use them.
* Put air into the tire to seat the tire beads and deflate. Then remove the silver valve core by hand and pump sealant into the tire through the valve stem. Use the quantity of sealant recommended by the sealant maker. Clean excess sealant out of the valve stem so it does not clog. Screw the silver valve core back into the valve stem by hand, and make sure the valvestem is screwed down tightly against the rim.
* Pump air into the valve (easier with an air compressor). Listen for the popping noise which means the beads are in place. Check that the beads are popped up on both sides. Ride the wheel for 1 mile/2 km so that the sealant disperses inside the tire and seals up any small holes.
When inflating using a CO2 are there any considerations to take into account?
It depends on the type of sealant you use. CO2 cartridge inflation can cause some sealants to harden. If your sealant hardens, then you have no puncture protection. You don’t want your sealant to get hard especially on the side of the road when you are depending on it to work!
Thanks for your time Bill!
A pleasure, anytime.
For more on tubeless wheels and the rest of the American Classic range check out their website, amclassic.com and to re-read just a couple of our previous reviews of tubeless wheelsets check out Jered’s look at tubeless from 2012 and Chris’ review of the AM Classic Argent Tubeless from last year.