were the bottom main tubes on the earlier diamondbacks smaller then the later models?i bought a set of old school stickers and had trouble getting the main tube sticker to wrap evenly.i got it as good as i could get but its bothering me because its slightly off.

What's earlier and later? The 70's to mid 80's DBs all had 1" down tubes. There are all number of dumb DB frame designs from recent years, emplying a number of dumb down tube sizes and shapes. Does yours have a gusset? as far as I know, all the DBs with diamond cut gussets had 1" down tubes. The properly sized decal for a 1" tube would wrap about 90-95% around the tube, but the two sides wouldn't touch.