Cutdown

A cutdown is a customised scooter (usually an Italian Vespa or Lambretta) with parts of the bodywork removed or cut away. Cutdowns were popular amongst skinheads and scooterboys during the mod revival of the 1970s and 1980s. While the style-obsessed British mod youth subculture of the 1960s prized the glamorous, metropolitan image of scooters, many skinheads and scooterboys viewed their bikes as simply a form of transportation.

While some scooter enthusiasts have focused on the stripped-down look, with just a bare frame and visible engine and mechanical parts, some scooterboys put back almost as much hardware as they had taken off, by adding customized chrome-plated accessories and racks.

Many cutdowns have unneeded parts removed to improve power-to-weight ratio. Typically, the fenders, leg shields, floors, tail section and cowls are removed. Cutting away body parts is the easiest with Lambretta scooters, because they are built on a tubular frame, which means that the body parts do not have a structural role. Vespa scooters, on the other hand, are usually built with a unibody design, so the body panels give the bike its structure. This means that when Vespas are cut down, they cannot be made as bare-bones as a Lambretta. The body panels of a Vespa are modified by slimming them down or giving them a different shape, in such a way that the structural soundness of the bike is not compromised.

Cutdowns are often tuned – much like a four-wheeled hot rod – by overboring the cylinders to increase engine power or adding performance exhausts, modified carburettors, or aftermarket shock absorbers. Some enthusiasts replace the standard drum front brakes with hydraulic disc brakes or add water cooling radiators. Lambretta owners may replace existing parts with a Nikasil plated aluminium barrel with radical porting, large Dell'Orto or Mikuni carburettors and bespoke (custom-made) expansion chambers, hydraulic clutches, and modern low-profile tyres. Some scooterists use aluminum Fabrizi racing barrels, because they use a rotary induction mechanism. Stock gas tanks may be replaced with increased capacity tanks, which put the weight of the fuel further forward. Some riders install a small fairing to reduce wind resistance and enable higher speeds and stability. To reduce weight, some scooterists use lighter-weight aftermarket parts, such as carbon fibre sports seats and other parts made from carbon fibre, carbon kevlar and fiberglass.

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