Thanks to Daniel den Hartog for his PDF of the 1982 Bridgestone Bicycles catalog, now online from the Bridgestone table of contents page along with all the other catalogs from 1985 through 1994 and a wealth of other information.
Isvan on Power Management
Osman Isvan has written a paper, Power Management for Lightweight Vehicles, and has been kind enough to send it for posting on sheldonbrown.com. Isvan gives special attention to how to make the most efficient use of electrical-assist power. His conclusions are probably not what you expect!
Sachs Elan/SRAM E12 Internals
John has posted a new article about the mechanism of the Sachs Elan/SRAM E12 12-speed internal-gear hub; the largest, heaviest, most complicated internal-gear hub ever marketed — flawed execution of a brilliant design concept. The unusual way this hub establishes its ratios carries an important lesson. In connection with that article, John has updated his article about the history of the Elan, his main page about Sachs/SRAM hubs and the internal-gear calculator.
More about Sachs/SRAM hubs
John has prepared a new page about the Sachs Orbit hybrid-gear hub and added information about this hub to internal-gears.html and sachs-internal.html; also links to Karsten Stielow’s very interesting Web pages about Sachs and SRAM hubs.
Shimano Internal-Gear Hubs
John has made major updates to the pages on Shimano Nexus and Alfine internal-gear hubs — 3-speed, 7-speed and 8-speed; also a page with general mechanical information.
Bicycle Video How-to
John has posted an article on how to synchronize video shot at the same time with more than one camera, and another on image stabilization. These are meaty technical articles.
Helmets
John has written an article about helmets and helmet issues. It includes a blast from the past, John’s photo of Sheldon in 1978 wearing a pre-Igor the Eagle helmet, and photos documenting changes in helmet design since the 1970s.
Assembly of Shimano 7-speed Hub Axle Unit
Shimano’s service instructions for the Nexus 7-speed internal-gear hub assume that you will replace the entire axle unit. Taking disassembly past the point where instructions are available is all too easy. You might also want to cannibalize parts to assemble one axle unit that works from two or more which do not. Reader Keith Lang has provided instructions in two PDF files. You may go to John’s introduction with links to those files..
Internal gear theory
John has posted his article on internal-gear hub theory, history and some practical advice. This article describes the internal workings of all the newest hubs including those with compound and multi-stage gearing.
Frayed cable
John has added a photo of a frayed cable to the article on cables.
