oldbobcat

Thanks for bringing that one up. I was searching for it online and too lazy to measure the crank on my old Masi. Oh, for the good old days, when we could complete the first half of a club ride using just the small chainring.

Duragrouch

Not for me. Looking at gear calc, with the old 52/42 I had 5 duplicate gears. With my current 50/34 applied to that same road bike, I would only have 3 dupes, and would not have needed to upgrade to a triple when I moved to hill country. (Although that triple low ring, is still 50% higher gear than my current lowest, shows how much lower my gearing has gone, on 20" wheels with a 30 cog low. It's the higher gears where I lost a lot of range, but 85 is enough.)

Camilo

Apologies for contributing to the recent veer off topic....

I've never understood why duplicate gears are a bad thing. That just means you can get the same gearing on either ring in some cases. Why is this bad?

Duragrouch

It's not the duplicated gears per se that is bad, but the lack of other gears that they squeeze out. My 14 speed with 5 dupes only has 9 actual gear ranges. Thus, the advantage of 1X gearing (no dupes), or wider steps between chainrings (many have done 20+), or the pinion bike transmission which advertises 18 speeds with no duplicates; In all cases you get more actual gears so finer steps between them. Right now I'm running 2X with 5 dupes, because it's cheaper than a conversion to 1X and better ground clearance, and I avoid IGHs because of maintenance that I cannot currently do, unless it's a Rohloff with all-oil lube, but that option costs 3X what my whole bike costs.

Having said that, if you are very careful with 2X gearing selection, you don't get dupes per se, but instead differences of half-steps, no perfect dupes, if you want to be switching the front ring all the time. This was the idea with old 3X touring gearing "half-step plus granny", like 52/47 with a bailout low of like 30 or less. I actually have this on my road race bike because I needed a triple for hills where I relocated, swapped my 52/42 with it from a bike that I would sell.

grumpus

It's mainly important when someone says "my bike has n gears" and 'n' is more gears than you have - you then inform them that actually they have fewer, because of all the duplicates.