That 'chopper' he's doing his charity ride isn’t a proper chopper. It has a raised, padded gel saddle and the gears have been moved up to the handlebars. He might as well be doing it on a Brompton. Still, I couldn’t do 300 miles in 4 days on one of them. I’ve only done about 200 on a bike I’ve had for ten years and approx 125 of them were done after I converted it to electric!