Shimano has new models of their groupsets every year but the lines generally keep the same names. This makes it difficult to figure out what year/version a particular bike has. Is there an easy way to figure this out and also determine which components/groupsets are better than others?
For instance, if I have Tiagra derailleurs from 2009 would they be better than Sora derailleurs from 2010 for a road bike?
Typically the majority of their yearly R&D is spent on their top of the line group, then they will trickle down it's technology to the next lower group, and continue that way, so usually, this years tiagra is close to last years 105, etc. The major thing to look for is # of speeds in a group, weight, and finish.
I believe the 2010 Sora(3400) set is a 9 speed, where the 2009 tiagra is a 9 speed - the major difference is the thumb button of Sora(3400) versus the finger paddle of Tiagra(4500), a substantial difference.
the quality goes 2200 < Sora < Tiagra < 105 < ultegra < dura Ace
