Originally Posted by
redlude97
Interesting. I'm kinda surprised since the 38c GK weighs 320g which is lighter(and thus more supple?)
GK is lighter than the Compass tires because the tread rubber is thinner at the centerline, but it's got a bead-to-bead protection layer which stiffens the tire significantly.
I haven't actually ridden on GKs, but I wouldn't be surprised if the Compass tires roll better.
The Bon Jon actually did fairly poorly in that test IMO. It tested faster than most other tires in the website's
touring category. It is not a touring tire.
And the Bon Jon did
extremely poorly in Tom Anhalt's testing on rollers.
I'm interested in whether these small-drum tests accurately capture the relative impact of sidewall flex versus tread flex. Tom Anhalt thinks they do, but his confidence seems to be based on a fairly shallow study, and I'm not convinced it's been well-characterized for the general case.