Half Step plus Granny

mandie

I am led to believe that this method of setting up your gearing for a touring bike used to be quite common.
I think that the idea was to have two chain rings that were fairly close in size (possibly a 44 and a 40) so that flicking between the rings gave roughly half the difference between the gears on the rear cassette. And then a much smaller granny ring as a bail out.

Does any one still use it? and are there any advantages for loaded touring over using a 48-36-24 on the front and a ninespeed 11-32 or 34 ot the back?

andrew_s

It is rare these days.

a) the gaps between sprockets are smaller on 9/10 speed cassettes than they were on 5/6, so there isn't as much of a benefit.
b) modern front mechs have deep inner plates that wouldn't clear a middle ring that's only a bit smaller than the outer.

It wasn't ever a particularly popular setup as it means that most changes are simultaneous front/rear changes. Enough people used it that you could get front mechs specifically designed for it, but it was still minority.

rickhotrod

Half step gearing means a double shift every gear change.

However, if you've only got a 5 speed freewheel and a double crankset it's possible to get 10 closely spaced gears. eg. 14-17-21-26-32 freewheel matched to something like 53/48 chainrings.

You would need a 9 speed double eg. 14-15-16-17-18-20-22-24-26 matched to a 53/39 to get a similar selection of gears.