Like its main competitors SRAM and Campagnolo, Shimano has a hierarchy of groupsets with levels offering different weights, number of gears and – of course – prices!
It’s important to remember that while each groupset name maintains its place in the hierarchy, they are usually updated every few years. So, for instance, when Dura Ace – Shimano’s top-of-the-line groupset – was launched way back in 1973 (as Dura Ace 7100), it was 6-speed; it is now 11-speed (Dura Ace 91xx).
I will try to keep this list current, please give me a shout if I mess up!
| Weight | Brakes | Rear sprockets* | Chainrings | Low sprocket max teeth** | Electronic | |
| Dura Ace R9170 | 2389 | Disc | 11 | 2 | 30 | Y |
| Dura Ace R9150 | 2051 | Rim | 11 | 2 | 30 | Y |
| Dura Ace R9120 | 2355 | Disc | 11 | 2 | 30 | N |
| Dura Ace R9100 | 2007 | Rim | 11 | 2 | 30 | N |
| Ultegra R8070 | 2627 | Disc | 11 | 2 | 34 | Y |
| Ultegra R8050 | 2353 | Rim | 11 | 2 | 34 | Y |
| Ultegra R8020 | 2512 | Disc | 11 | 2 | 34 | N |
| Ultegra R8000 | 2266 | Rim | 11 | 2 | 34 | N |
| 105 R7025 | Disc | 11 | 2 | 34 | N | |
| 105 R7000 | Rim | 11 | 2 | 34 | N | |
| Tiagra 4700 | 2585 | Rim | 10 | 2 or 3 | 34 or 32 | N |
| Sora R3000 | Rim | 9 | 2 or 3 | 34 | N | |
| Claris R2000 | Rim | 8 | 2 or 3 | 34 | N |
* the more spockets, the smaller the jump between adjacent gears.
** the more teeth, the easier the bottom gear will be.
