I bought a mid-1990s rigid MTB. Really 'fugly' looking monster-of-a-bike . The FD didn't work when I bought it, so I removed it and just use the big ring up front (42T). The 42T ring is OK for commuting with a load, but if I wasn't regularly carrying stuff I'd probably jump up to a 48T, or change cranks to a 50/34 compact and add a new FD (the old-style MTB frame will work with a 50/34 road crank). Rear cassette is about 11-32, only use the smallest gears (11-13-16- 20 ?). Added some puncture-resistant 26 x 1.5 street tires, a rack in back & basket up front, and I put fenders on in winter - I'm a happy camper.