SunTour Fahrradbauteile: Unterschied zwischen den Versionen

In the early '70s, Sun Tour freewheels were a revolutionary development, markedly superior to their European competition (Atom, Cyclo, Everest, Regina etc.)

[Bruce Dance reports: All SunTour freewheels are date-coded using the two-digit date code system as described on the Trek vintage and velobase sites. The oldest 'Perfect' I have is a 'Q' so probably 1974; it is also marked '8.8.8' and 'Maeda Industries' but not marked 'Sun Tour'.]

First SunTour freewheel to hit the US market was was the "Perfect", mainly a 5-speed system, though 6-speed versions are not rare. The Perfect used 2 or 3 splined sprockets, and 3 or 4 threaded ones.

There were 3 different 6-speed spacings used on Perfect and Pro Compe freewheels:

See the spacing cribsheet on this site for more detail on this topic.

Perfects usually have a bronze or gold finish on the sprockets; Pro Compe, a silver finish, but the sprockets otherwise are interchangeable. Sun Tour 8.8.8. Gold 5 speed freewheels were Perfect variants. The gold-finished sprockets were a cosmetic touch. There also was a Pro Compe tandem version with a black body, wider pawls, a 16-tooth ratchet and better-finished bearing races. This was only ever sold in a 5-speed version.

Sun Tour Winner, New Winner and Winner Pro freewheels usually came with silver-colored sprockets, like the Pro Compe.

Bruce Dance offers the following observations:

When the 'Winner Pro' and 'Alpha' series were launched they also (confusingly) launched a middle model which they called the 'Winner'. So there are two SunTour freewheels called the 'Winner', separated by about ten years.

WP/W/Alpha bottom sprocket body splines were intended to accept an 8-spline version of the bottom cog. However none of the freewheels I have from this period have anything other than the original 4-spline sprockets as per the 'New Winner' freewheel fitted. I don't know if they ever made 8-spline cogs in any numbers.

Sun Tour's innovations in shifters paralleled those in freewheels and derailers.

Derailer-equipped bicycles in the 1960s and early 1970s usually had downtube shifters, which required removing one hand from the handlebar. Some low-end bicycles had handlebar-stem mounted shifters, which looked good to newbies but which offered no way to stabilize the hand against vibration. They also posed the risk of injury to sensitive pars of the body. Sun Tour had answers to these problems.

Sun Tour Barcons (handlebar-end shifters) were the favored shifters for use with drop handlebars from the mid-1970s until the advent of index shifting in the late 1980s. These shifters allow precise control by wrapping the thumb and index finger around the handlebar end, operating the lever with the palm of the hand and the other fingers.

Traditional shift levers held their position against the cable pull by friction of the cover plate against the lever body. Friction was controlled by screw, sometimes with a D-ring handle so it could be adjusted during riding. Tightening required a hard pull against both the friction and the cable's tension. The Barcons had a patented feature, a ratcheted assembly so the friction only counteracted loosening of the cable.

What Barcons did for bicycles with drop bars, the Sun Tour thumb shifter, which mounted just inboard of the handlebar grips, did with flat bars. It conquered the mountain-bike market in the early 1980s.

by Ashok Kumar

Sun Tour stopped producing components in March of 1995. The name was bought by SR, but the component designs did not survive.

Using SunTour Perfect, Pro Compe and New Winner freewheels

Sun Tour Freewheels article on Yellow Jersey site

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