Originally Posted by badger_bike
Tentatively in the market for a new bike. Unfortunately, the brand/model (Kona Smoke) I'm most looking at is only sold in a few less-than-accessible locations in my area, *and* I don't know what size I need. So: I'm wondering how much difference there is in the sizing of bike brands, and if it's fine to get sized on some random brand (say, a cannondale or specialized) of comprable model so I have a general idea of what size I need on the bike I actually want. (my current bike is a 15" framed specialized hardrock, and is too small for me, but I suspect I only need the next size up --on specialized that's 17", but on Kona that's 18").
Find the right size in said "random brand." Then go to the web sites of that brand and of Kona and pull up the geometry specs for each bike. Compare standover height and top tube length to match up the proper size.