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so having read most of that, for a 12 and bit stone rider on GP4000S2's in 25c guise, I should be at about 90 PSI both ends...i think ?
I go about 80psi on Michelin Pro 4s.
Similar weight.
There appears to be much more margin for error anyway, I've had no flats at all since I went 25c.
again, people are confusing rolling resistance with speed - from Macavity's link
Dear Lennard,
Before I go out and buy myself some fatter tires, what testing have you done with aerodynamics? Does the increased wind surface area with the larger tires cancel the positive effects of lower rolling resistance?
— BradDear Brad,
Very good question. As you’re probably aware, the aerodynamic data put forth by Hed and Zipp in support of wider rims for improved aerodynamics shows that it definitely depends on the rim. In general, if you ride very fast, the aerodynamic drag of the fatter tires will cost you more in speed than the rolling resistance benefit will gain you
If you're fast you'll be faster on narrow tyres, if not then go for the a fatter tyre
hilldodger - Member
again, people are confusing rolling resistance with speed - from Macavity's link
Not all of us. Few of us ride fast enough for aero to be everything. Comfort (and suspension losses, what do Zipp say about those?) and resulting fatigue are relevant, if psychosomatic.
23mm Vittoria Tubs - 140psi
25mm Schwalbe Ones - 100psi
not sure i can tell the difference
I used to find anything below about 100psi was too puncture prone for riding on normal roads - commuting say.
80psi seemed low even for a race in the wet a couple of weeks ago
Noooo, fat tyres and low pressures is the way to go - a mountain biker told me on the internet 😆