Gearing Choices

Posted: 2011-06-16

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Question
What kinds of GEAR CHOICES are available on a Bike Friday travel bike?

A Bike Friday can be equipped with any standard gearing system available on the market, and no, you don’t have to pedal more.

You can choose from a wide range of cassettes to give you up to 27 speeds. If you know all about “gear-inches” click here for a gear chart calculator, otherwise our Sales Consultants can help you work out what kind of gearing you need.

Here is a selection of the most popular options:

* Chainrings This is the traditional setup: single, double or triple front chainrings in conjunction with a rear cassette of 7,8, or 9 cogs. The number of chainrings depends on how many gears you think you need, which in turn depends on your fitness and the terrain, but as a general guide, use single for flattish commuting, double for sport, moderate hills and light touring, and a triple for loaded touring, big hills, mountain biking and tandem touring. In combination with the right 7,8 or 9 cog cassette in the rear, you can achieve up to 27 speeds.

The advantages: simple, light, and can be repaired anywhere; it is a standard system the world over.

The considerations: fairly large chainrings need to be used to compensate for the smaller 20″ wheel diameter, typically 53-62 teeth. In addition, the front derailleur is yet another piece of equipment that can be knocked out of alignment during travel, a problem which is completely eliminated by the SRAM Internal Hub system if you choose that kind of gearing, described below.

* SRAM Dual Drive 3 speed INTERNAL HUB: This is an innovation that works particularly well with the Bike Friday’s 20″ wheel diameter. The system looks like this: single front chainring (no front derailleur), and in the rear wheel, an enclosed, planetary gear system that performs the same function as the front chainrings, in combination with a standard 7,8, or 9 cog cassette to give a total of 21-27 gears.

The advantages: Wider gear range than a triple chainring, robust, bullet proof casing which makes it great for touring. If you climb really steep hills or like really low gears, this is it! Unlike earlier editions of this hub, you can shift it while pedaling.

The disadvantages: generally a pound heavier than a typical chainring setup, and though it is a reliable component, it is not as easy to repair on the road in the unlikely even that it fails. However, it is designed to be a fully enclosed, relatively maintenance-free system.
* ROHLOFF SPEEDHUB: A completely internal gearing system: single front chainring, no front or rear derailleur, no cassette, 14-speeds evenly spaced (no overlapping) gears, yet with as wide a range as a triple chainring. Operated by a single grip-type shifter. Was developed for mountain bike downhill competition.

Advantages: Bulletproof, wide range of gears.

Disadvantages: Heavy (typically almost a pound heavier than the SRAM setup), expensive, more drag and a whirring noise which is music or menace to your ears depending on whether you’re a fan or not. Needs to be run in: after the first 500-1000 miles, the oil should be changed out – a simple procedure.

* CAPREO: This 9-speed cassette, usually found in 9-26 speeds, allows the use of standard chainrings (eg 53/39). The Capreo is made from 105-quality parts.

Advantages: It shifts better than other cassettes. Replacement rings are easy to find. It is a lighter option than dual drive.

Disadvantages: There is only one hub, freehub, and cassette available, and each is unique to the Capreo. No lightweight Dura-Ace version is available, for example. In addition, replacement cassettes or hubs may be difficult to find.