Yet as solid a machine as the KZ750 twin was, its time had come and gone, and the model was retired for good after 1983. Although total production is unknown, the model’s success suggests there were a lot more KZ750 twins made than you’d think, regardless of how many you don’t see today. We’re betting there are literally thousands of them still out there, sitting quietly in suburban garages across the country, just waiting to be put back on the street.

Two-cylinder alternatives to the KZ750
1977 Yamaha XS650
- 53hp @ 7,000rpm/ 105mph
- Air-cooled, OHC parallel twin
- 5-speed
- Single-disc front, drum rear
- 428lb (wet)
- 40-50mpg
- $1,500 - $3,500

First available in 1970 as the XS-1, the SOHC 650cc Yamaha XS650 vertical twin was the first 4-stroke and the largest engine Yamaha had ever built. Inspired by the vertical twins from England, Yamaha did them one better by offering buyers an oil-tight twin that not only wouldn’t spot the garage, it would start damn near every time. Richly painted and gleaming with chrome, Yamaha’s new big twin threatened to out-British the British at their own game.

Until you rode one, that is. Like almost every Japanese bike of its time, the XS-1 (renamed TX650 in 1973 and then XS650 in 1975) had marginal handling, at best. Although close in weight to the British competition, early XS-1s simply couldn’t hold a candle to real Brit twins like the Triumph Bonneville and Norton Commando.

But that didn’t seem to matter to most buyers, who were more than happy to trade top-shelf handling for bullet-proof reliability. Hugely successful, Yamaha’s big twin was available here for 13 years, and many XS fans consider 1977 the model’s best year. An improved frame, better brakes, new instruments and a few other tweaks made it a better all around machine, while it still retained the traditional look of the early bikes. Cheap and reliable, the XS is possibly the perfect classic rider.

1977 BMW R80/7
- 55hp @ 7,000rpm/ 110mph
- Air-cooled, OHV opposed twin
- 5-speed
- Dual disc front,  drum rear
- 473lb (wet)
- 45-55mpg
- $2,500 - $4,500

Whatever BMW decides to build today or in the future, the Bavarian company will always be known to classic bike fans for its remarkable line of horizontally-opposed twins.

Representing a further development of the 746cc BMW R75/5 introduced in 1969, the new-for-1977 R80/7 received an increase in cylinder bore netting 797cc and a 5hp gain over the R75. Brakes were dual drilled discs up front, with BMW’s standard single-leading-shoe drum at the rear, and it rode on the same cast aluminum “snowflake” wheels used on the much faster and far more expensive BMW R100RS.