Join Date: Dec 2006
Bikes: lots... even a Raleigh twenty !!!
Some R20 owners use the original SA 3 spd hub with new rims, others use either a SA 8 spd or a Shimano Nexus 8 spd IGH, those 8 spd hubs are not light, so there's not much weight loss there. If you're prepared to tinker then, some guys have converted to a 6 or 7 spd cassette hub and RD set up and shaved weight off that way.....(you might find that the smallest gear on a 7 spd will be too close to the frame and will rub)
The best weight loss for the drive train would be going to a single speed or fixed gear, a very pure form of cycling...hope you don't live/ride in hilly areas.
Using lighter materials for the seat post, head stem, brakes etc etc will shave some weight as well.
If you have a UN72 BB then make sure it's 73mm wide and the spindle is approx 113 or as close as possible, any longer and you will have trouble achieving a straight chain line. If you don't have one yet....good luck finding it, they getting hard to find!!