Lowering the gearing on a Bike Friday
My wife and I own are planning a multi-month tour of Europe, plenty of mountains. We would like to lower our gearing. We currently have the Sachs 3-speed hub with 44 x 11-30. Our convential touring bikes, Co-Motion customs, give us granny gears with 17.88 and 18.56 gear inches.
Any suggestions on lowering our Llama gearing to be closer to our Co-motion gearing?
There are two options for lowering gearing. The first and simplest is to change the front chainring. In your case, changing from a 44-to a 40-tooth chainring will lower your gearing to 91.0 gear-inches on top and 17.9 gear-inches on the bottom.
This can be problematic as lowering the gear inches by lowering the number of teeth on the chainring lowers the entire gear range. Perhaps a better solution is to change the cassette to an 11-34 which would lower the low end to 17.4 while leaving the high end as it is currently. The derailleur must be capable of shifting such a range–most mountain bike rear derailleurs will do so without any problems.