I'm planning to put together a touring bike built on a Salsa Vaya frame http://salsacycles.com/bikes/vaya/va...e_frame_build/ . I've settled on SRAM x.9 9-speed rear derailer and x.9 trigger shifters but am very confused about the crankset and front derailers.
First, I notice on many bikes, including my own, that the manufacturer specifies higher quality components for the rear than the front of the drive train. Does that indicate that the front components are less critical? Cranksets in particular seem to range vastly in price and I have no idea how to proceed. Component weight is not a big issue for me and ny advice would be welcome. Are chainrings and bottom brackets normally separate purchases from the crankset?
Second, I'm looking for a 22-32-44 crankset compatible with the SRAM 9 speed rear derailer but most cranksets i see say they are 10 speed. Does this refer to the spacing between chainrings? Will a 10-speed crankset work with a 9-speed chain and cassette?
Third, will another brand of front derailer work with the SRAM x.9 trigger shifters? The built Vayas come with a bottom pull derailer but I can't tell if it's high or low mount. How can you tell? What difference does it make?
Fourth and final question, how are "mountain bike" components different from "road bike" components? Is it only the size of tubes they mount to and the style of handlebar they are intended for?
I know it's a lot of questions and I wil very much appreciate any information you can provide.