South Salem Cycleworks Online
(503) 480-2001
We have a huge stock of vintage and modern parts. Contact us!

Vintage Components - Simplex Alpha rear derailleurs

On this page: Simplex Alpha T Version 2

We do not have an on-line shopping cart at this time. Please call us: (503) 480-2001 or email:

Simplex founder Lucien Juy owned a bike shop in Dijon, France, when he began making his first derailleurs in 1928. His innovative designs were a hit and by 1933, Juy said he was making 40,000 derailleurs a year.

It wasn't until 1961 that Simplex adopted the deforming parallelogram that Campagnolo had popularized with its ground-breaking Grand Sport derailleur a decade before. But Juy's Simplex derailleurs had a sprung top pivot, the way all derailleurs are made today. At the time, that Simplex Export 61 was probably the best-shifting changer made.

A year later Juy decided to make Simplex derailleurs out of an acetal resin (OK, plastic) made by Dupont called "Delrin". It was a terrible mistake. Juy took what was the best derailleur in the world and turned it into a flimsy, delicate changer.

In the early 1970s Juy again began producing superb changers when he came out with the alloy Super LJ series. They were nicely finished, well-designed, good shifting derailleurs.

No amount of innovation or quality improvement could stem the Asian onslaught, exacerbated by association with those delrin derailleurs that came on so many bike-boom bikes. Simplex ceased production in the 1990s.

Simplex Alpha T rear derailleur, Version 2. Used, $40.00

Part# 75305

  • The Alpha was made in the early 1990s, making it one of the last derailleurs Simplex produced.
  • This derailleur is made of Delrin & steel. The top and bottom pivot parts are Delrin and the rest appears to be steel.
  • Simplex kept fussing with the Alpha derailleur design. There appear to be four versions of which this is the second.

Simplex Apha T rearderailleur

Not very many of these derailleurs left.

Simlpex Alpha T rear derailleur

And from the back