Road and cyclocross tire performance and safety

Are tubeless clinchers better than tubulars?

Dear Lennard,

I’ve been reading your tubeless posts. Do you think road tubeless tires are unsafe?

Matthew

Dear Matthew,

If you have been following my posts this last month since Andre Drege’s death in the Tour of Austria, you know that I consider the combination of carbon rims and tubeless road tires to be less safe for pros to race on than tubulars. The same goes for riders who descend aggressively enough to crack their carbon rim if a pothole appears around a blind corner that they are going too fast to avoid. This is because hitting the rim hard enough to crack it will decrease its circumference, and then the one thing retaining the air and holding the tubeless clincher tire onto the rim is gone, namely the precise fit of tire bead to rim bead seat. The tire will instantly deflate, and its bead(s) will drop into the rim valley, allowing the tire to come off the rim with even the smallest of lateral force applied. This stands in stark contrast to a tubular, which can be ridden flat, remaining glued to the rim.

While rolling resistance tests I have done showed that some tubeless clinchers roll faster than current top-end tubular tires, it’s possible that may have as much to do with the lack of investment in tubular development as in an inherent difference between the designs. That road pros have largely switched from tubulars to tubeless clinchers has everything to do with their sponsors and their investment in tubeless technology, not with riders freely choosing.