Originally Posted by
stapfam
Bought my last bike only a few months ago and a compact 50/34 with a 12/25 cassette. That is not a hill bike for me but will be when the Tiagra 30t goes on it.
Originally Posted by
Monoborracho
I run a compact double Ultegra 50/34 with an XT - 11/32 mountain bike type on my road bike. It draws a few looks and comments from people at the rest stops on hilly charity rides, usually of the variety of "why didn't I get that" ?.
These quotes bring up new questions. While searching I read some posts about swapping a Tiagra cassette for a 105 and even one that talked about swapping two rings from something (I think Tiagra) into an Ultegra cassette to build a custom set with a wider range. So, it sounds like there is a lot of flexibilty in these things. What are the actual differences between the various 10 speed cassettes (Tiagra, 105, Ultegra) other than tooth counts -- different materials? And does a degree of interchangeability extend to other brands or just within a brand? Going even further to Monoborracho's situation, does switching all the way to an MTB cassette require changing the rear derailleur and or the shifter or can you just pop a new one in?