raleigh Reynolds 501 opinions

Could only really find classified posts on these. Was looking for an opinion on whether they make a decent bike have seen a geared racer for £150. Was thinking would this be a suitable replacement to my carrea TDF?

Bless.if its in better condition than your current bike.
Specially chainrings and cassette. Could be a good buy.
Don't take any notice of 531 is awesome etc posts

My raleigh record sprint made from 501 weighs about 12kg (8 speed geared) the same as the carrera.

I find it very comfortable to ride though for strong riders it is probably too flexible, I have no concerns in that area.!!

I've just been given a raleigh reynolds 501 frame that I was thinking of using as a project, but I'm struggling to find much info about compatibility of flip-flop hub wheels, cranks, etc. The old wheels were 27 x 1 1/4, would 700c fit?

Any advice greatly appreciated.

Yes they'll fit, will be a bit of a gap tho as 700c is slightly smaller. The brakes might not reach the rims but chances are they will, if not you'll need a brake with a longer drop. 700c wheels in 27" frames just look fucking awful...
Bb threading on old raleighs is different to standard english so either use the old bb cups if they're in good nick or get it rethreaded.
Basically, its a cheap old bike, get it running and enjoy it, don't spend big money on parts unless they'll go on a nicer frame further down the line.
Sheldon has plenty of info on old raleighs iirc, go read and learn.