Yeah, curiously, he seems a bit undergeared. At 120 rpms assuming 27 inch wheel size he'd only be doing 83. According to the article he had to do 180 rpms (three rotations per second) to hit his top speed. That's consistent with his pushing 220 gi, since he'd be doing 42 mph at 60 rpms and 42*3 is almost 130. (gotta love Sheldon's calculator!)

Edit: After reading tfa it says he was pushing 225.