The 1980s and 1990s: improved engineering and aftermarket suppliers

   In 1984 Harley-Davidson, who had been using chopper inspired styling for a number of years, released the 'Softail. A design that hid the rear shocks under the engine creating a profile that looked a lot like a hard-tail. This frame was initially offered in the Softail Custom, a bike that took many styling cues from choppers, including the narrow 21" front wheel. Buyers looking for the chopper look had a plausible factory alternative, and interest in choppers declined.

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With some time out of the limelight chopper builders seemed to work on craft more than wild innovation in this period. While individual builders still built long bikes, the trend was towards more moderate geometries, and the basics of how to build a good handling but still great looking chopper became more common knowledge. In this period it became possible to assemble a complete chopper using all aftermarket parts, companies like S&S built complete Shovelhead style replacement engines, frame makers such as Paughco offered a variety of hardtail frames and many bikes were built using these new repo parts. Super long girder and springer forked bikes were less popular in this era, while the use of telescopic forks grew, and builders upgraded to larger diameter tubes in both forks and frames to gain more rigidity.

Japanese bike builders offered a dizzying array of new bikes, including full-faired racing styled machines as well as many 'customs' that picked at chopper styling in a random way and rarely achieved the powerful integrated style that more and more custom chopper builders in this era seemed able to consistently achieve. As materials, fabrication and knowledge improved the performance of the better choppers improved. More powerful engines drove the need for stronger frames, brakes and bigger tires with more grip. These trends worked together so that as the 1990s closed the modern chopper was larger looking, more powerful machine. The widespread use of CNC made it possible for even small shops to fabricate out of block aluminum, and billet components became a signature item often replacing stamped and chromed steel components of the earlier eras.

                                                                                                                                en.wikipedia.com