Raleigh Chopper rear wheel, featuring a red line around the sidewall. In 1969 the Raleigh Chopper was launched in the UK market this was a triple launch for Raleigh, with the Chopper branded as THE HoT oNE, alongside the Moulton Mk3 (The Smooth One), and the RSW Mk3 (The Dolly One). The Chopper bike was sold as a "must have" item and signifier of "coolness" for many children at the time. The Mk 2 ("Mark 2") Chopper was an improved version sold from 1972. It had the rarely-purchased option of five-speed derailleur gears, and the gear lever shifter changed from a knob
Bicycle suspension Horst Leitner began working on the problem of chain torque and its effect on suspension in the mid-1970s with motorcycles. In 1985 Leitner built a prototype mountain bike incorporating what became known later as the "Horst link". The Horst Link is a type of four-bar suspension. Leitner formed a mountain bike and research company, AMP research, that began building full-suspension mountain bikes. In 1990, AMP introduced the Horst link as a feature of a "fully independent linkage" rear suspension for mountain bikes. The AMP B-3 and B-4 XC full-suspension bikes featured optional disc brakes and Horst link rear suspension very