[9] The SunTour derailleur cost less than Campagnolo, Huret, Shimano, or Simplex and it performed especially well shifting under load, as when changing to a lower gear while pedaling up a steep incline.

Although their system, called Five-Speed Click, worked well, it proved an idea ahead of its time and did not catch on with the riding public.

In comparison, SunTour chose to continue with its existing research and development staff of some 20 persons, and remained primarily a bicycle gear and shifter manufacturer.

[9] As Suntour derailleurs and shifters could be specified on many more low- and mid-priced bicycles, the company gained a reputation with the general public as a producer of only low-end equipment.

[7][8] This reputation would eventually hurt sales when Suntour introduced a complete high-end component group, Superbe Pro.

Next was the introduction of the Micro Drive 94/56mm BCD five-bolt compact mountain bike crankset, which saved weight, increased ground clearance, and permitted lower gearing for hill-climbing.

The first sign of trouble came with returns on SunTour's SR MounTech rear derailleur, caused by failures of the innovative spring-loaded jockey wheel that was fitted with a seal that proved inadequate to keep out dirt and mud.

SunTour no longer had the resources to debug prototype designs before introducing them to the market, which cost the company in returns, repairs, and damaged reputation.

It had to borrow additional cash to finance a transfer of manufacturing facilities to Taiwan, as well as begin development of new mountain bike components.

With two years of lead time, Shimano could afford to require that bicycle manufacturers equip their bikes with complete SIS shifting systems, minimizing problems with product compatibility.

[12] In 1988 the SunTour name was purchased and revived by Sakae Ringyo Company, (now owned by Mori Industries Inc.) with a capital investment of 45,000,000 NT$ in Tokyo, Japan, thus becoming SR-SunTour.

Mori Industries left the bicycle component business, selling off SunTour's Japanese facilities piecemeal and closing its U.S. offices in early 1995.

[6] In 2012, Junzo Kawai, former president of SunTour Japan, returned to bicycle component manufacturing with a new company called SunXCD.