Originally Posted by LWaB
Half-step is a better system for touring but can't be set up with more than 6 cogs. Modern front derailleurs don't cope well with triples AND 4-5t differences.
While modern gearing set-ups work well except for really wide ranges (think tandem), there are still the problems of excessive dish in the rear wheel and short-lived chains and cogs. Personally, I'd like to run half-step on my touring and tandem bikes again. The drivetrains used to last much longer.
Today's narrow chains and fat crank spiders prevent half-step gearing, because the chain will tend to fall between the rings or to ride up over the top of the smaller one.
I like half-step gearing because one can obtain relatively large ratio ranges while making the superior rear derailleur do most of the work. If does not absurdly high gears (anything over 100 gear-inches, in my book) or super-low gears, a 2x7 or 3x6 setup provides good coverage and excellent shifting performance. The other trick I used in my 10-speed days was to have two different inner chainrings, giving me a tight 50-47/14-16-18-20-23 half-step for fast, level rides and wider 50-42/14-16-18-20-23 1.5-step for hills. I have the same setup today, but with the welcome addition of a sixth cog, a 26T grannie.
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Capo: 1959 Modell Campagnolo, S/N 40324; 1960 Sieger (2), S/N 42624, 42597
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