Mavic's Speed City wheels, disc-brake-compatible 700c wheels with the 135mm rear-axle spacing common to mountain bikes, allow riders to put easy-rolling skinny tires on their disc-only-equipped mountain bikes in a flash, far quicker and easier than removing knobbies and putting slicks on your 26-inch mountain bike's rims. The Speed City's larger diameter rim, combined with a low-profile road tire, should drop into most disc-equipped mountain bikes, even full suspension, with no clearance problems.