I picked up an 87 Sprint the other day at a yard sale in near new condition. Paid 15 bucks. Being an old school weight weenie, I threw it on the scale and it came in at 33#. I noticed the Made in Taiwan sticker, and figuring it is probably a Giant frame, thought I might change a few things. After replacing the steel wheelset with Weinmann alloys, the steel cruiser bars with aluminum, took the springer seat off and replaced with a Schwinn "racing" seat, (no changes to rd fr or crankset) reweighed complete at 25#. Rides really nice.
It's a lot more components than frame that dictates a decent ride.