Unlike a traditional geared bicycle the brompton can contain a 2 speed derailleur plus a 3 speed internal gear hub. Specifically the standard single speed has 12t rear sprocket and 54t front chainring.
When considering brompton gearing the options are a minefield.
Brompton gearing. A brief overview of how to use the 6 speed brompton to get the most out of the gears. 1 speed for flatland riding. The 6 speed version has 13t 16t rear sprocket and 50t front chainring.
How do you reach a suitably informed decision. Brompton folding bikes come in 4 gearing options including the single speed 2 speeds 3 speeds and 6 speeds. Standard gearing is achieved using a 50 toothed 50t chain ring the front cog.
The 3 speed version has 13t rear sprocket and 50t front chainring. Bromptons lightest gear option. On the left side was the selector that controlled the 2 speed derailleur.
You can choose from 6 speed 3 speed 2 speed or 1 speed and then fine tune your choice with or options. The brompton derailleur system is designed specifically to give optimum shifting on the short stays and small wheels of the brompton bicycle. Sturmey archer gears on a brompton they work reliably with a minimum of effortbut what if something goes wrong this short video explains how to adjust your.
The brompton standard gear range bsr provides three evenly spaced gears so you can climb hills cruise in normal traffic or haul ass when you have a tailwind or when being chased by your neighbor s dog. We offer several different gear options and dealers will make recommendations depending on your specific riding conditions. As the brompton tensioner is not designed for such a dramatic gear differential it barely provides sufficient movement to keep the chain tensioned and allow folding in either gear so a slightly worn chain might cause problems.
If you really hate hills and want your brompton geared lower than this the 44t will lower all your gears by 12. Brompton offer three levels at which you can pitch your gears high standard and low. The 2 speed version has 12t 16t rear sprocket and 54t front chainring.
This tiny hand brazed bicycle had a gear selector on both the right and left handlebars. The first time i test rode a brompton folding bike it was a 6 speed.