Should You Go Tubeless? Within the cycling industry, some companies have fully committed to road tubeless with multiple models while others dispute the claimed advantages. There are divergent opinions on BICYCLING’S test staff, too. Read on to decide if this new technology is for you Pros Cons Flat Protection Anecdotal evidence from our testers suggests that tubeless systems incur fewer flats than tubes. But, current road tubeless tires are thicker and heavier than high-end, nontubeless clinchers, making a comparison difficult. Also, almost all of our riders use sealant inside their tubeless tires, but not in their tubes. Still, we’ve found that road tubeless is a solid choice for rough pavement and gravel roads. Limited Selection There are currently 25 tubeless road wheels and 10 tires on the market. More options are on the way, but nothing like the breadth of products available for cyclists riding standard clinchers. Only one tubeless tire is wider than 23mm (Hutchinson Intensive, a narrow 25c) and just two carbon wheelsets—Corima’s Aero+ Tubeless (also sold as the Hutchinson RT1) and Mad Fiber’s clincher. Lower Pressure Road tubeless was designed to work at lower pressures than most road clinchers. Hutchinson, which developed road tubeless with Shimano, recommends that cyclists use as much as 13 psi less than they would run in a tube. Running less pressure means the ride quality will improve; some riders claim the ride is as smooth as a tubular tire. Lower pressure also boosts traction when cornering and braking, because softer tires stick to the ground better. But some claim that the ride isn’t as supple as high-quality, traditional tubulars or even the best open clinchers. More Maintenance Working with road tubeless wheels and tires isn’t as simple as handling a regular clincher. You have to be patient when working stiff beads on and off rims—a process that often requires soapy water. You have to be careful about choosing tire levers, repairing punctures, and installing valves, rim tape, and strips. You also need an air compressor to properly install many tires. You have to remember to refill the tire with fresh sealant every few months—and if the sealant can’t fix a puncture out on the road, the repair is much more time-consuming and complicated. Security Hutchinson says that its road tubeless tires, built with no-stretch carbon beads, cannot roll off the rim, but we’d hate to be the unlucky ones to disprove this claim. Assuming Hutchinson is right, the tire will stay on the rim should you flat. Sloppy If you ditch tubes, you should use sealant. But putting it into the tire can be messy, and inserting a tube in the event of a bad cut will be even messier. You’ll also need to strip the old goop from the rim when it’s time to add new sealant. OUR TAKE Switching to tubeless won’t save you a lot of weight the way swapping to tubulars can, and setup and maintenance are a little harder than normal. Once everything is together, the system requires a little more vigilance, but and the ability to run lower pressure offers a smooth ride and good traction. We don’t foresee tubeless exponentially gaining popularity until a more varied lineup of wheels and tires is available—especially lighter, more aerodynamic wheels and fatter, lighter tires with more efficient casings. Eventually, we could see tubes relegated to jersey pockets and seat bags, coming out only when a tubeless tire fails catastrophically. How Does Tubeless Compare? Lab tests comparing tubeless road tires with standard clinchers have not been conclusive—perhaps partly because they’ve been conducted in a lab instead of out in the real world. The only consistent finding we can draw from existing studies is that companies making and selling tubeless products find them to have lower rolling resistance than tires with tubes. Companies not on the bandwagon say those claims are bunk. To help form our own opinion, we performed one of the oldest evaluations in the cycling industry—a roll-down test—on tubeless tires from Hutchinson and Maxxis, comparing them to a standard tire from Michelin. It was a basic experiment: Starting from a dead stop at a specific spot on a hill, we coasted down until the bike stopped, then measured the distance traveled and quantified speed via GPS. We controlled as best as we could variables such as rider and position and used equal pressure (100 psi, front and rear) on the same wheels (Giant P-SLR-1) mounted on a Pinarello Prince test bike. We completed all testing in a short time span to minimize any effect from changing weather and did six trials with each combination to try to average out variables beyond our control, such as gusts of wind. Tire Distance (meters) Average Speed (Km/H) Maximum Speed (Km/H) Michelin Pro4 Service Course w/ latex tube 200.05 21.35 34.20 Hutchinson Fusion 3 RT 195.63 21.28 33.54 Maxxis Padrone 194.03 21.26 33.54 Michelin Pro4 Service Course w/ butyl tube 193.99 20.68 33.18 Conclusion Although we don’t advise that you consider the results of our limited test completely conclusive, we think the broader findings are interesting and more than likely reflect real-world use: With a latex tube, a top-of-the-line clincher was fastest; the tubeless tires were grouped tightly, reflecting, we believe, the current lack of variety in products; heavier butyl tires with clinchers were the slowest combination; and, most significantly, the differences in speeds are not yet so great that a rider can’t compensate for it in other ways. http://www.bicycling...beless?page=0,0