This sled has the original big 760 JLO engine, twin-cylinder and air-cooled. Model #:760 JPA. It came from the factory with the twin chrome side pipes. In recent years these have been called "montana pipes" however I do not recall hearing that term back in the day. This sled was purchased new by a family friend right here in central MN and is still very original. This sled also has accessory electric start, speedometer and tachometer; all of which are still operating.