Here is the catalog of Dia-Compe (Yoshigai). The catalog is thick, has many pages. It means that Yoshigai was going well in those days.
Various products, such as the one which had been produced since Yoshigai had business tie-up with Weinmann, or the MTB parts which became popular recently were introduced in this page.
I show the English catalog (A5 size 32 pages) in this page.

This was the front cover. It was the simple design which emphasizes the brand mark.

Royal Gran-Compe which was the highest grade model of those days was printed on the backside of the front cover.

Here were the contents.

This was the highest grade model Royal Gran-Compe. RGC series of upper side equipped with the forging brake shoes.

New Gran-Compe and Gran-Compe are on upper side. Aero Gran-Compe is on down side.
NGC400 was first short arch model of Yoshigai. The quick release of this year was a type which you could stop at any position.
Aero Gran-Compe was very small model. The trait of it was adjustment of a brake shoe.

Here were so-called Compe G and the standard type side-pull models. The models that the cable was attached to the right side had been produced since business tie-up with Weinmann.

These were standard type side-pull models. Three models of the upper left have been used for general bicycle until now. The product life is very long.

These were the models for BMX. I've just noticed the centre-pull model.

The models of the down side were supplied for Bridgestone and Miyata of those days. Bridgestone had advertised it as a self-centering brake in those days.

I think Yoshigai already quit producing the center-pull brakes. Those were used for the high grade sportif bicycle of mass-production maker. GC had the most beautiful finishing work, G was second grade, and DC was third grade.

These were the cantilever brakes. The design of 960 series was almost same as CLB of France. It was very popular model.
Back in those days, people used to feel that they had become veteran cyclist after they exchange this brake for Mafac Criterium cantilever. I myself also thought the performance became good because of good function of Mafac. It was the matter of old days.

980 series was a early model which improved the clamping power for MTB. It was not the low-profile type yet.

These were popular models which were made of steel.

Various brake levers were introduced through 10 pages from here.
Royal Gran-Compe and Aero Gran-Compe were introduced in this page. Aero Gran-Compe was a built-in cable type which is popular now.

Here were New Gran-Compe and Gran-Compe. A number of cyclists must have used them.

Here were Compe-G and Standard. Various sorts of product were prepared in the lineup because of the combination of quick release, adjuster, and lightening hole.

The red shaft under the pad is nostalgic. It has been produced for a long time since Yoshigai made business tie-up with Weinmann. I suppose there must have been a lot of cyclist who had attached a lever pad to their first drop handle bicycle for upgrading.

These were new types which had thin bracket. 204QC which was not the built-in cable type is produced even now.

This is the nostalgic safety lever!
Back in those days, adult used to attach this lever to kids bicycle because they thought the drop handle is dangerous. When kids got used to it, they began to feel shame as cyclists because the safety lever was for beginner.

Here were the levers for flat handlebar. 135 was a Weinmann type.

BMX became popular in those days. The power lever which was strong and easy to grip had appeared with the BMX boom.

These were the short levers for BMX.

Back in those days, Guidonnet lever was often used for camping bicycle and mixte bicycle. The Reverse lever which was called "Opposite lever" was used for promenade bicycle.

These were stems. Gran-Compe which had triangular neck was one of popular domestic model in those days.

CF and DC was a general model.

Here were several small parts such as cable hanger, straddle cable bridge. 1243 was a reasonable pulley type cable bridge. It was one of easy-upgrade item.

Here were straddle cables, direct attached brake plinth, and pivot bolts.

Offset bolt was used when people use small arch brake to the frame which was made for large arch brake. I'm not sure how often it was used. Various brake shoes were introduced from this page.

Here were brake shoes and several sorts of small parts.

There must be a number of cyclists who are suffering about the lever pad because it became rare nowadays.

Here were the several tools and the outer cables.

This is the chart for the shoe stroke and suitable rim width.

This is the back cover. The address of head office of Japan and USA were printed on the page. Cane creek road in US address seems to relate to Cane Creek that Yoshigai had made business tie-up recently.