Tag: speed

Sturmey Archer S3X Fixed Gear 3 Speed Hub

Sunrace Sturmey Archer have published details of a new fixed-gear 3-speed hub, which is currently at the prototype stage.

The details are as follows:

  • Overall gear range is 160%.
  • Direct drive is 3rd gear, with reductions of 25% and 37.5%. This translates as gear steps of 20% and 33%.
  • This The hub will feature a "much stronger aluminium hubshell".
  • No details are given about shifters, but a "bar-end style shifter" looks a possibility.

The new S3X is a new interpretation of the Sturmey Archer ASC hub, which was a Fixed Gear 3-speed hub produced from 1946 to the late 1950s.

The S3X has a wider ratio than the ASC, which had an overall ratio of 133% (-25%, -10%, Direct).

Some links for information on the ASC hub:


The Sturmey Archer ASC 3-Speed Fixed-Gear Hub, from Sturmey Archer Heritage

The full Sunrace Sturmey Archer blog post is below.

Tuesday, September 2, 2008
S3X Fixed Gear 3 Speed
So I know there are many of you out there that are very interested in the little bit of info I recently got my paws on.

The first batch of prototype Fixed Gear 3 speeds is finished. The new hub will be called the S3X. The hub will be made using a much stronger aluminum hubshell. Overall gear range will be 160%.

* 1st Gear -37.5%

* 2nd Gear - -25%

* 3rd Gear - Direct Drive

* Gear step gear 1 to gear 2: 20%

* Gear step gear two to gear 3: 33%

Shifters are still up in the air but we have had many requests for a bar end style shifter. Also we are still planning on the possibility of doing some anodized colors with laser etching instead of screen printed graphics. Please comment on what you would like to see in the way of shifters or color choices.

Rusty old bicycle!

From Times Online

A rusty old bicycle expected to raise just £1 for charity was sold on eBay for more than £500 to a collector in Japan who identified it as a rare British classic.

The yellow bicycle was given to Bruce Symes to raise money for Dart Sailability, a charity for disabled sailors. Mr Bruce, of Galmpton, Devon, gave it a guide price of £1 but bids were soon placed from the Far East – including Taiwan and Korea.

Collectors noticed that the bicycle was a Moulton Speedsix – the first six-speed bicycle made in Britain, with only 600 produced in the 1960s. It was sold for £537.

New "Silent" Hubs from Shimano

From VeloVision Online...
Alfine and Nexus 8 hubs get 'smooth' roller clutches instead of pawls...

Shimano have announced a change to their 8-speed internal gear hubs. Previously, like most such hub gears, they used a freewheel-like system of pawls to ensure one-way rotation of various internal parts:

This does of course create a clicking sound...

Now they've moved to roller clutches which are near-silent in operation:

These also offer, they say, quicker engagement, which should make shifting a little faster. This final image shows how the new hub internals use three of the roller clutches:

The 'smooth' hubs have new part numbers:
- for roller brake SG-8R31 (std), SG-8R36 (premium)
- with coaster brake SG-8C31 (std), SG-8C36 (premium)
- Alfine (for disk brake): SG-S501

Betcher!

I found this video, from 1971, quite by accident. It's a film made for the Department of the Environment, to promote the National Cycling Proficiency Scheme. There are a few Moultons to be seen, with children from both groups riding them.

Experts will be able to identify the exact Moulton models, and spot a few Moulton suspended cars, apart from the obvious Mini Moke!

My observations:

  • Pity the Moultons weren't more central to the plot, but it was nice to see the Chopper (or at least its rider) being taught a lesson or two.
  • It was nice to see the "prize" was a sporty, but also functional bike. It had mudguards, mudflap, lights, bell, etc.
  • I was struck by how calm the streets were. The traffic was relatively light and moderate in speed, very few parked cars, and no inappropriately over-sized vehicles.

If that's got you in the mood for some nostalgia, have another look at these old CTC videos

Obico: The Ultimate Bike Computer?

The Open Bike Computer, or OBiCo is a fascinating new bike computer project.

It can be used as a normal bike computer, of course. But it can also be used as a heart rate monitor (taking input from Polar and Sigma brand chest straps), a music player (it plays OGG as well as MP3) and a GPS receiver. It takes an external memory card (the widely available micro-SD card), has a high quality TFT screen and a USB interface for connection to a PC.

The USB connection can be used to charge the internal lithium ion battery. Alternatively (and this deserves a drum roll) a hub dynamo, such as the Schmidt Original Nabendynamo (SON) can be used to charge as you ride.

You may at this point have noticed that it's very unlike a typical commercial bike computer, lacking proprietary accessories and software... well it gets better, much better.

The Obico will come with a custom API for software development. So if you're not happy with the software that comes with the device, you can write your own.

It will also feature the Embedded Linux operating system to the Obico could be used just like a regular computer, in so far as any Linux computer is regular!

The main features of the Obico are:

  • No batteries required! A hub dynamo will be used to charge a li-ion cell.
  • Easy to use.
  • Audio interface, so you can listen to your favorite music while cycling.
  • High quality color tft-display, that adapts automatically to the lighting conditions.
  • Visualization of:
    • speed
    • heart frequency
    • odometer
    • audio data
  • Logging your tour data like GPS coordinates, heart frequency, speed and other parameters to a MicroSD-Card.You can synchronize these data with your PC lateron. The amount of logged data depends on the size of your SD-Card.
  • GPS support is planned as an option. Location plans are scheduled.
  • New program features for this computer are for free and can be downloaded from this webpage.

The main processor is an ARM9 derivative. It is supported by a second processor, which controls the peripherals and assumes the tasks of the power management. The obico board has the following features:

  • 32 / 64 / 128MB Mobile SDRAM
  • Micro-SD Interface
  • AC97 Audio Interface to play MP3, OGG, ...
  • high quality, background lightened TFT-color display
  • HRM - Receiver (Pulse band receiver)
  • GPS - Receiver (optional)
  • 3 axis gravitation sensor
  • ambient light sensor
  • Lithium Polymerakku, that is loaded per USB or dynamo

It's still at the prototype stage, but if this project were based on genuinely open standards and free software, and received good development community support, this has the potential to be truly groundbreaking and revolutionary.

http://www.obico.de/