Tuesday, June 10, 2008

On Rolling Resistances of Wide Tires

"Wide tires do not roll slower at lower pressures. In fact, testing indicated that a wide tire at lower pressures rolls faster than a narrow tire at high pressures, if all other factors remain the same. Even narrow tires can be ridden at comfortable pressures with only very small concessions to performance.

Perhaps the most important result of the test is that tire pressure does not significantly affect rolling resistance. Wide tires in particular do not need high pressures to roll fast. But because many current wide tires are designed to handle high pressure, they have strong casings that lack suppleness. This results in higher rolling resistance than necessary."

- Road Bike Rider Newsletter (2006), based on Vol 5 No. 1 issue from Bicycle Quarterly http://www.bicyclequarterly.com. The test included nine 700C tires, seven 650B tires and two tubulars. The protocol and results were reviewed by industry experts.

Courtesy : Velo Chimp


thePig said...

Wow that surprises me. I always thought that fatter tyres had more resistance.

hmmm....now I am going to need to find a new excuse as to why I go so slow.

Brucemeister said...

Years ago I had inside info that Cyril Guimard (at the time Bernard Hinault's DS) instructed his team mechanics to inflate the tubs up to 110 psi, not beyond. His idea was that the lower psi resulted in a more comfortable ride with no compromise of rolling resistance, with the result of a fresher rider at the end of the day. Looks like he knew something....

Anonymous said...

I really respect and miss the issues of Bicycle Quarterly. They had some very sound technical articles.

Anonymous said...

This is why tubeless makes so much sense. Low pressure, but not risk of snakebites. Great cornering grip. No increase in rolling resistance.

BTW - I have the new Dura Ace 7850SL wheels with Hutchinson Fusion Tubeless tires and they are sublime. I've sold all my tubulars except for a nice set of Mavic Cosmic Carbone Pros with Vittoria CXs.

Anonymous said...

The tires were difficult to mount dry. However, a little soapy water on the beads and it was a snap.

True, I can't tell a difference in rolling resistance, but so long as they are not SLOWER, I find the other advantages are significant.

I agree that at speed aero means everyhing. But, the tubeless are great for my training, group rides, rides in the mountains with lots of hard cornering, etc.

I've never flatted them and they lose about 10psi per night.