i think it makes a lot of sense to upgrade an old bicycle if it has a quality frame. i have two raleigh super

course mark 2s from 1975. these frames are not the the cats meow, they are reynolds 531 straight gauge in the main tubes only. while i have nicer bikes (all 531 db holdsworth pro & a klein team super) i feel the money i spent on my super courses was well spent. this was raleighs least expensive quality bike, it came with alloy rims & without the raleigh propriatery threading, & i really like those bikes. the raleigh model below the super course was the grand prix & this was raleighs best selling bike boom model, it was all steel except for the alloy brakes. the competitor in peugeots line was the uo-8 & i believe peugeot sold ten of thousands of them, they were nice too.