When we purchased the bikes, we traded out the standard chain ring (with 28, 38, and 48 teeth on the three rings) and replaced it with a 22-32-44 chain ring. This has provided us with much lower "granny gears" for the hills. The cost of this change is a loss of pedal power at higher speeds. For those familiar with gear inch measurements, we changed from a range of 22.2 - 117.8 inches (standard chain ring) to a range of 17.5 - 108.0 inches with the chain ring we use. In practical terms, this tradeoff means that we are able to usefully pedal up steep hills at speeds as low as 2.5 mph. But on downhills, once we get up over 31 or 32 mph, we can no longer pedal - the pedals just spin, unable to do any work. Any speeds we have achieved faster than that have been due purely to gravity! For our touring objectives, this tradeoff has been well worth it, and has enabled us to say that we have never walked a hill on any of our tours (except for a couple of ridiculously steep driveways)! For others who are stronger riders and who like to hit the higher speeds, this choice of chain ring would not be for them.