Brand: Royal Enfield
Model: Constellation
Years: 1958–1963
Engine: 700 cc twin
Notes: Originally with 52 bhp with "R" cams and single TT carburetor in 1958 and 1959 and twin carbs for 1960 to 1962; Weak bottom end proved unreliable and was progressively detuned to 40 bhp to make it more reliable. Unique scissor-action clutch operation. In 1961 and 1962 a "bathtub" model with a unique fiberglass rear end was also sold.[7]
Source: Wikipedia