It'll take paint and decals off.
Heres how I do it.
pour nitromorse in small amounts into a bowl and then paint onto frame with a paint brush, leave the paint to bubble and take off with course wire wool pads or a paint scraper. I strip it in sections, rather than all at once as well. you'll probably want some medium wire wool to clean out the detail and just smooth it all out when finished. Doing it that way rather than all at once leaves you far more in control of what your doing and less fumes about the place.
WATCH YOURSELF, nitromorse isnt nice stuff you want the proper thick rubber gloves like you get from gardening centre, marigolds wont do, it'll melt them. goggles or the like too, its not stuff you want in eyes. plenty of ventilation as well for the fumes.
In all honesty if you know someone who will beadblast it for cheap enough do that, If its a pub bike and you can get it blasted/powdercoated for about £50. It'll cost you £35-40, stripping, priming, painting and putting lacquer on it and in the middle of winter its a bloody nuisance.
trust me, I did it last week.