JesseN wrote:
Tom, Great data, this starts to shed some light on what has been a murky but very important subject. Of the tires you tested my experience is limited to the GP4000S and the G-One 40's (close enough) and my perception of the extra load on the G-Ones seems to jive with what you measured.
I'm not sure I concur with the G-Ones being 'dogs' - they aren't a road tire after all. There is a price to pay for versatility in these tires and I think the G-One balances that better than other tires I've tried (Clement MSO, Kenda Happy Medium). I haven't done any offroad riding from the 'big smooth tire' approach so I can't vouch for how much knobbed traction matters, if at all (probably very surface dependent?).
One other interesting question would be the RR vs. pressure relationship for some of these tires. I know it's been well established in the smaller sizes for lower RR with lower pressure. FWIW I would never take my G-One 40's above 40 psi even on tarmac (lower offroad). I would presume that relationship holds here as well.
Coming from a long-time MTB background (bought my first MTB in 1986) I was quite skeptical of how well a "smooth" tire would perform off-road. But then experiences such as originally participating in the BWR on smooth, narrow road tires and then riding an Exploro 2 years ago using the WTB smooth tires on the Dirt Demo single-track trails demonstrated to me that they actually do quite well!
Those experiences had me setting up my original "Frankenbike" all-road rig with 50+mm wide Compass Rat Trap Pass tires.
The key seems to be using a flexible enough tire at a low enough pressure to allow the casing to conform over most off-road obstacles. About the only places I've found them to "fall down", is on relatively steep bumps that have loose gravel on them and in mud. Everywhere else, they do surprisingly well.
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