Originally Posted by
el forestero
I frequently climb long, steep hills and am trying to decide whether it's worth buying an 11-34T cassette for a bike that has an 11-30T cassette and a 34T small chainring. When riding up continuous grades of 10% to 20% for 40 to 120 minutes at a time, how noticeable would the difference be between running on 30T and 34T cassette cogs? Is each pedal stroke likely to feel significantly easier on 34T or does this feel like a subtle change?
I think you yourself are in the best position to answer this. If you've been doing these climbs, at what cadence are you pedaling with the 30T setup? Everyone is different, but typically it wouldn't be ideal to be lower than 70rpm. Your proposed gear addition would net you about a 10rpm increase at those ranges.
