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Sun Tour Bicycle Parts

by Sheldon "They're Gone" Brown

A Work in Progress

Most Perfects are limited to a 14 tooth minimum.

Some later 6-speed Perfects had an extra smaller diameter thread that would fit a 13. Sprockets up to 38 teeth were available.

There were 3 different 6-speed spacings used on Perfects:

• Standard (wide) six speed spacing (same distance between sprockets as a 5-speed.)

• "Ultra Six" narrow spacing to fit 6 sprockets where 5 used to be. This spacing later was adopted as the seven-speed standard.

• There was also an in-between 6-speed spacing used on some O.E.M. Japanese bikes, particularly Fujis.

Then there was the Winner, a short lived, high-end version of the Perfect. I don't know too much about this model.

Then came the New Winner, which used the most of the same sprockets as the Perfect, but was also avaialble in 7-speed. The same body could build 5- 6- or 7-speed clusters.

The New Winner had adjustable bearings, using a special pair of pin wrenches; there was a cone and a locknut, basically as with a wheel bearing. This would go to a 12 tooth sprocket in 7-speed or wide 6 versions.

Then came the Winner Pro, which went back to conventional shim-adjusted bearings, but was better sealed than previous models. The Winner Pro also had more splined sprockets and fewer threaded sprockets.

The Winner Pro briefly offered an 11 tooth option in the wide six format.

The Winner Pro also introduced the 4-prong extractor (previous models used 2-prongs.)

The New Winner and Winner Pro usually came with silver-colored sprockets.

There was also the Alpha series, basically a cheaper version of the Winner Pro.

Leonard Caplan wrote:

> > I have some NOS Suntour 8.8.8. Gold 5 speed freewheels. Where do they > fit is the scheme of things?

Those were Perfect variants. I believe the bodies were the same, but the gold finished sprockets were a cosmetic touch.

For those who care, here's more about old Sun Tour freewheels:

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

Sun Tour freewheels provided much better shifting than older designs due to the superior design of the sprocket teeth. The tops of the teeth were not squared flat nor grooved, as with older designs, but were asymmetrical, with a slant inward. This provided a sharper outside corner of each tooth for better chain pickup, and the slant helped the chain slide down sideways into good engagement if it was tending to run along the tops of the teeth.

It was possible (and not unheard-of) to assemble Sun Tour freewheels with some of the sprockets backwards, which markedly degraded shifting performance.

(European freewheels with grooves running along the tops of the teeth were prone to a semi-freewheeling mode as the side plates of the chain would skate along the grooves.)

I used to regularly modify Regina and Atom freewheels by re-grinding the teeth of the sprockets so that they somewhat resembled those of Sun Tour or Shimano sprockets...a treatment later known as "Sheldo-Glide."

Another advance pioneered by Sun Tour was in the area of freewheel removal. Although they still stuck with the traditional two-prong remover design, they provided much deeper notches and a matching tool that provided a considerably better fit. The result was a much lower incidence of damaging tools or freewheels.

Sun Tour also popularized the use of splined sprockets. Previously, the vast majority of freewheels used all threaded sprockets. Typically, the two largest would have left-hand threads and screw on from the back side of the body, while the smaller sprockets would screw on from the right. A freewheel would typically have 3 different threadings for sprockets in the different positions.

Sun Tour replaced the left-threaded large sprockets with a spline design using 4 splines. This made it possible to replace all of the sprockets without removing the freewheel from the hub. Traditionally, the largest sprockets were the most difficult to unscrew, because they would get screwed on the tightest during hill climbing.

Sun Tour did not invent splined freewheels. Cyclo previously offered a deluxe model called the "Pans" that worked the same way, but this was mainly offered to racers to facilitate gear changes to fit the requirements of specific courses. Sun Tour brought this design to the mass market, and made the all-threaded systems obsolete.

ultra wide range systems 34, 38 teeth

Barcons

Thumb Shifters

Slant-pantograph derailers Skitter vGT

Low normal

I've become kind of a Suntour afficionado and therefore have spent some time researching the various road components that the company produced. It's difficult to locate comprehensive information, so I am putting some of it down here. I'll focus on the higher-end road groups and also some of the interesting and esoteric parts I've come across. I'll try to do it chronologically. A useful source for me has been the article "Sunset for Suntour," although it is more of a historical overview:

http://www.users.globalnet.co.uk/~hadland/page35.htm

Another interesting part came in 1966, Suntour's Spirt (not Sprint, or Spirit) front derailleur. It was a "top normal" derailleur, in that you move the lever in the opposite direction to shift up or down. Thus both shift levers move the chain to a higher gear when pressed forward. Apparently the Spirt was produced for some time. Rivendell sells 1978 models for $15. http://www.rivbike.com/webalog/shift...urs/17107.html

Not much information is around from the late 60s or early 70s. I think the top model from around that time period was the Suntour V.

In 1975 Suntour introduced their Cyclone derailleurs, the new top model. They were quite a bit cheaper than Nuovo Record and shifted very well. 1975 Suntour Parts Catalog: http://www.wooljersey.com/gallery/v/.../SunTour/1975/

In 1977 the new top group was Superbe. This year also saw Ultra-6 spaced freewheels, which allowed a rider to run a 6-speed freewheel with 120mm dropout spacing. In 1979 Ultra-7 allowed 7 speeds with 126mm. Superbe remained top of the line until 1981. 1980 Suntour Catalog: http://www.yellowjersey.org/stour80a.html

Suntour Symmetric shifters were an esoteric piece of early 1980s Japanese engineering. They could be mounted on frames with a single DT shifter braze-on (like some of the Shimano AX components took) or with a supplied clamp-on belt. They are unique because shifting the rear derailleur automatically trims the front via a cam mechanism. Unfortunately, the trim only works as you downshift the rear derailleur, so as you go back and forth, the trim will eventually move the FD too far inward. Interesting nonetheless. http://www2.flickr.com/photos/slchang/35285580/

In 1981 Superbe Pro was introduced. Good stuff, the early to mid 80s Superbe Pro friction group is probably my favorite. Commands a premium price on ebay (I would know, I'm selling a group on there right now). Superbe was now second-best, with Cyclone below that. ARx, AR and BL (Blue Line, which featured interesting blue details on the components) were also introduced. Brakes and brake levers were rebadged Dia-Compes and I think the cranks and BBs were made by Sugino (all the ones I've seen come with a Sugino marked grease condom, in any case). A picture of the 1985 Superbe Pro group (bottom image, the top is Superbe from 1979): http://www.classicrendezvous.com/Jap..._sup_grp79.htm

Blue Line:

http://www.classicrendezvous.com/Jap..._blue_line.htm

A note on Superbe Pro BBs: Suntour used a weird taper for their Superbe Pro BBs of the time. The closest match other than a Superbe Pro BB would be Campagnolo square taper, from what I understand. I think this is the approach that Phil Wood recommends.

In 1985 Shimano introduced indexed SIS shifting. Suntour underestimated the necessity of a competing product and postponed development of an indexed system until 1986, at which point SIS had become quite popular. During that year, Suntour Accushift was quickly developed.

In 1986, the Sprint group appeared, a friction group placed in between Cyclone and Superbe (Superbe Pro was dropped for a year). The Sprint shifters included a ratchet mechanism (Suntour Power Shift) that disengaged the friction mechanism as you pull back. A lot of people like this design, and it is often compared to Simplex retrofrictions. There are Suntour barcons that use the same design. There had been ratcheting models on lower end Suntour groups previously, and future Accushift models would also have ratchet modes. You can buy Suntour LD-4850 Power Shift levers at Velo Orange. These are Sprint shifters. http://www.velo-orange.com/suldsh.html

In 1987 Accushift was introduced. There were technical problems. Further market share was lost to Shimano. Accushift groups included Superbe Pro, Sprint 9000, Cyclone 7000, α-5000, and α-3000. Non-indexed versions of the second- and third-best groups' RD and levers were referred to simply as Sprint and Cyclone. Superbe was dropped. The easiest way to tell the difference between the newer and the older Superbe Pro groups is the logo font. Newer cranksets used 130bcd instead of 144bcd. Aero brake levers were introduced. 1987 Suntour Dealer Catalog: http://www.wooljersey.com/gallery/v/.../SunTour/1987/

In 1989 the lineup was changed again. From top to bottom: Superbe Pro, Sprint, GPX, Olé, and Blaze. Olé was a response to Shimano Santé and featured white details. Didn't really take off. 1989 Catalog and additional scans from around the same time:

http://www.yellowjersey.org/stour89a.html

http://www.equusbicycle.com/bike/sun...tourscans.html

Most of the problems with Accushift had been cleaned up by 1990. Superbe Pro was still top-quality componentry, but Shimano had taken over the market. Superbe Pro sealed hubs were of course excellent. There was the famous hidden spring brakeset which functioned well and is now collectible. Suntour SL replaced Sprint in 1991. A bit from the 1992 catalog:

http://www.yellowjersey.org/stour92a.html

Superbe Pro BRS Hidden Spring Calipers:

http://www.yellowjersey.org/brax2.html

One last unusual piece of engineering was the Suntour Command Shifter. They were something like STI or Ergo and mounted just inside the brake levers on the handlebars. The front shifter had the ratchet system, the rear could do either indexed or friction modes. They worked well, save for the fact that you couldn't shift from the smaller to the larger chainring from the drops (which is when you would want to do so). If you were clever, though, you could solve this by using the Suntour Spirt derailleur I mentioned before. A picture of command shifters:

http://www.ivycycles.com/misc/Desktop-Pages/Image9.html

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

Some Japanese pages with pictures and information on Suntour parts.

http://members.jcom.home.ne.jp/suntour/

http://translate.google.com/translat...&hl=en&ie=UTF8

Suntour freewheels:

http://www.yellowjersey.org/stfw.html

Most of this has been cobbled together through online research, so it might not all be correct.