I am in the process of reworking my wife's mixte, which is a Coventry Eagle, a very nice light lugged steel frame made from Tubi Oria Cro-Moly. It currently is a five speed using mostly Simplex parts in the drive train, Maillard? hubs with no name 700C rims, and Wienmann brake levers and side pulls. I am not sure what year it is, but it is a very nice looking and handling bike.
I want to add a chain ring or change the crank set to have 2 chain rings up front. It has 120mm spacing on the rear, so I am not sure what the maximum amount of cogs I can get in that space. I want to use all Campagnolo parts, does not need to be from the same vintage as the frame or even all need to be a certain group. This choice is the result of me picking a bike up along side the road with Campagnolo parts. The frame is too large for anyone in my household but it does have Campagnolo Gran Touring Novou front and rear derailleurs with down tube shifters.
So can anyone tell what groups or vintages to look for that would allow me to build a high quality yet economical bike for her. There seems to be a huge array of groups, names and vintages out there. I planning to replace the parts in this order -
Drivetrain - I have the front and rear derailleur and shifters, need to find the crankset and freewheel. Can I fit a 6 speed in 120mm?
Hubs and rims - Need to source all parts. Since this is mostly a touring bike, what the best spoke count? Front & rear?
Brakes - Levers and callipers - need to source all parts
Also how difference is there practically between 170mm cranks and say 175mm?
Thank you for your time
P. Lynn Miller