I'm considering the Nashbar compact crankset to upgrade my 1976 chrome-moly road bike (already has 700c wheels, 7-speed cassette and other upgraded components). The Nashbar compact crankset comes in 170mm, 172.5mm and 175mm lengths. How do I know which to choose? I'm a 155-pound man who stands 5ft 10, and I'm 50 years old and doing about 100 miles/week on rolling, hilly roads and some bike paths. No racing for me.
Also, I was planning to take apart, clean and rebuild the bottom bracket anyway, with new BBs and cups if they show pitting, regardless of whether I change the crankset. When I do this maintenance on the bottom bracket, can I simply pop the new compact crankset onto the existing old bottom bracket parts? The original crankset is an alloy double 130 bcd made by Takagi, in 170 length.
Would there be an advantage if while I have it taken apart I change it to a cartridge system instead of the loose bearings?
Please advise on what I'll need to install the nashbar compact crank. I've already bought the appropriate tools. Thanks.