In some cases, due to the shortness of tube butting etc. Tube replacement can be expensive, therefore, retrofitting may sometimes be impractical. Painting isn't a factor on a new frame since paint is part of the manufacturing process with or without couplings. Step through refers to your ability to, literally, step through the middle of the frame of the bicycle. The longer the spoke is the more leverage can be exerted against it. Since then owner Peter Stull has been working with senior engineering students at Alfred University , local engineers and machinists utilizing available technology including computer FEA testing to improve their recumbent bikes. For framebuilders , it's simpler to build a new frame because they install the coupling in a tube in advance, then they miter the tube assembly to fit the frame. Some builders can change the profile of an odd shaped tube to make it accommodate a round coupling so check with your framebuilder before ruling out the possibility of fitting odd shaped tubes with S and S Couplings. Folding bikes available specifically designed for travel, leisure, commuter, or sport. A Bike Friday consultant will promptly reply to serve your individual needs. The UCI no longer considers the bike Chris Boardman rode for his record to be in compliance with its definition of an upright bicycle. Bicycle performance Over distances recumbent bicycles outperform upright bicycles as evidenced by their dominance in ultra-distance events like 24 hours at Sebring. Well, the same is true of bicycle spokes- the longer the spoke the more flexible it is, and the more likely it is to bend or break. Recumbent commuters often add flags, lighting, and reflective material to their bikes and gear to enhance visibility, and many refer to being able to see eye-to-eye with the automobile drivers as an advantage. Various types of Mochet-designed derailleur gears were fitted, with a single gear for the track models.