Bicycle Mechanics - Compact Crank for 7 speed Shimano 105

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atwbiker
12-29-07, 11:00 AM
I have an older Giant Cadex 980C with a shimano 105 7 speed drivetrain. I want to put a compact crank on this bike. Is it possible? If so, what do I need to look for when purchasing the cc? I assume some will and some wont' work. Will I need a whole new drive train or can i just retrofit the cc? What info am I not considering that I should?

Thanks for your feedback!

DieselDan
12-29-07, 01:13 PM
You should be able to switch out without too much trouble. If you have a triple crank, look into 110BCD touring cranks.
Gonzo Bob
12-31-07, 06:25 AM
If you are going to be reducing your big ring, check if the front derailer can be lowered enough. You will need to lower it by about 2mm for each tooth you decrease - i.e. if you go from 53T to 48T, you will need to lower it by ~10mm. Some frames (esp carbon) have bracket mounts that don't let you lower them much.

roadpig2001
12-31-07, 06:49 AM
No problem , you will probably also have to change the BB . I assume you are currently using a square taper . If your current cranks have 110bcd just change the chainrings .I have seen some deals on sram cranks with outboard bottombrackets on ebay.