SRAM Force crank set with 9 speed Tiagra group/105 RD?

Jeovany Thomson in LA wants to know if you can mix Shimano 9 speed 105/Tiagra gears with a SRAM Force 53/39 chain set and what difference this might make over the original 50/36?

Question:
Hi, I have just purchased a 2010 Masi Vincere Road bike. It has a 9 speed 12-25t cassette and Tiagra shifters/FD and was wondering if having a SRAM Force crank set is compatible with this set-up. The original stock crank set is a 50/36 tooth while the Force is a 53/39 tooth. I don’t know if that would make much of a difference.

Hi Jeovany.

The SRAM Force chain set is probably for 10 speed, but should work with a 9 speed chain and your other 9 speed kit. You will notice a difference between the two chain sets as there is quite a jump between the 53 and the old 50. You will have quite a higher gear ratio, which is handy to have, 53 x 12 is a big gear, but has its uses.

The difference between the 39 and the 36 will also be noticeable; you will lose some very low gears. Personally I find 39 x 25 ample for most nearly any climb. If you are considering riding in the Alps or the Pyrenees then the 36 chain ring can get you up anything.

The 36 is good if you are in a hilly area and don’t want to push a hard gear, or if you have or are getting over an injury. You could find that you build up more power as you will have no choice but to use the bigger gears for climbing. In the end climbing hurts, with a lower gear you are slower and it takes longer, with the bigger gear it also hurts, but you get it over with quicker!