The Altitude is designed to fit up to a 27.5" x 2.5" or 26" x 3.0" tires. Keep in mind, there can be differences in tire widths between different tire manufacturers even if they are listed as the same size on the sidewall. We recommend checking the clearance before riding to ensure that you will not damage your frame. We recommend 6 mm of clearance between the tires and any frame members.