If you'd prefer a bike rack that's connected to the central seat post and not the frame, Blackburn has an Interlock Seatpost Bike Rack that installs two ways, depending on seat height. There are no frame mounts required, and it fits posts from 22mm to 32 mm in diameter. The Central Seatpost Bike Rack is constructed with aircraft-grade 6061 aluminum tubing for strength and durability, and it can carry weight up to 22 pounds. Special touches include light and reflector mounting loops. This Bike Rack works well with most trunk bags and panniers, but is designed to work with Blackburn's interlock bag system.