Harley-Davidson introduced the Softail chassis in 1984

Harley-Davidson introduced the Softail chassis in 1984. The original Softails used the small FX telescopic forks, but the FLST Heritage Softail with large FL telescopic forks was introduced in 1986. The FLSTC Heritage Softail Classic, with large front forks and retro styling, was in production by 1988.

Other Softails with big forks followed, including the 1990 introduction of the FLSTF Fat Boy and the 1993-only FLSTN "Cow Glide". The base FLST Heritage Special was discontinued in 1991.[14] The FLSTN was continued after 1993 without the bovine motif as the Nostalgia model until 1997, when it was replaced by the FLSTSC Springer Classic.[14] The Springer Classic is also designated as an FL despite using Springer forks instead of the large FL telescopic forks.

In 2000, all Softails, including the FL models, were switched from the Evolution engine to the counterbalanced Twin Cam 88B engine specially developed for the rigid engine mounting in this frame.

The FLSTN designation returned in 2005 with the Softail Deluxe. The FLSTN Deluxe, which was introduced in 2005, also came with an option of carb or EFI models.[citation needed] The year 2005 was also the last in which a carb was offered on all HD models.