Originally Posted by
scottfsmith
Thanks, this is starting to make some sense now. My regular rims are 21mm ID and I don't recall feeling any squirming at 60psi in front. I could probably go even a bit lower, I might try out 55psi in front given these 15% drop numbers.
Yep, some of the calculators factor in the internal rim width. Going from 17 to 21 mm rims on the sram calculator drops the pressures by about 5 psi. It applies that to both front and rear tyres, but it's the front I notice squirming too much at lower pressures.