Monday, February 8, 2021

IBM Selectric Typewriter Cycle Clutch Hub Pulleys

 As many of you may know, I've been reproducing the Cycle Clutch Pulley, also known as the Main Pulley or Main Hub for IBM Selectric typewriters for a few years now. This grew out of a necessity to source replacement pulleys for the Selectrics that I reconditioned. The original pulleys were injection molded nylon that crack from age. Many of these pulleys are 40 years old or older, so you can't really blame IBM for a bad part since they lasted well beyond the design life of the Selectric. IBM stopped providing parts support for all typewriters when Lexmark was founded and Lexmark stopped supporting all typewriters, even Lexmark branded ones many years ago. Without a supply of replacement Cycle Clutch Pulleys, these typewriters are unrepairable and wind up in landfills.

At the time, I had over 100 Selectrics that needed Cycle Clutch Pulleys. There was no way I would ever find 100 good used pulley from parts machines, so I decided I needed to try to make my own. Making the drawing of the pulley was the toughest part as it is fairly complicated and needs to be highly accurate. I chose to make the part from aluminum so the part would last as long as possible. After a few tests and few revisions, I started installing them on Selectrics that I was refurbishing. They worked great and once I was satisfied they performed properly, I let other Selectric repairmen know about them. That's when I started selling them on ebay and directly to people who knew me.

After a few years, I've sold over a thousand of these pulleys and used hundreds of them myself. I've sold them all over the US and many foreign countries. If your Selectric has the dreaded "thump thump thump" sound, then you need a Cycle Clutch Pulley. Just contact me.



  1. How do we contact you? I have a 1930s Royal that needs cleaning. Appears to work but needs to be cleaned well. I don’t see contact info anywhere on the blog.