Originally Posted by DMNHCAGrandPrix

I rode 27 x1 1/4 Serfas Seca tires for a couple years before recently trying the same nominal size Panaracer Paselas. The mounted and inflated Serfas were obviously narrower than their listed size (28 mm actual, rather than 1 1/4=32 mm listed). In contrast, the Paselas measured very close to the predicted/listed size (32 mm). The Paselas also ran higher off the rim, increasing the effective wheel diameter, and reducing fender clearance to the point of creating a problem of rubbing between tire and fender. I readjusting the fenders to the maximum possible clearance under the fork and rear brake bridge and was able to solve the clearance problem. So far I've been enjoying the ride of the wider tires, but wish all manufacturers were more consistent with their listed and actual sizes!