My 1970's Mistral has Campy Rally gear. 54/39 up front with 6 speed cluster in back. So it's a 12 speed. I want to go to about at least 18 speed and preferably 21 speed. What's the best way... cold stretching rear frame to 130mm ? find a Campy triple chainwheel ? or both ? BB width would also be an issue I guess. Any suggestions/ideas appreciated.

Thanks. cankiwi6@telus.net