I have a GT Aggressor 3 which I really like but is getting worn out. Want to keep this frame and have the chance to buy a Scott g zero fx 2 which has a broken frame. Is there any point trying to build a bike from the 2? Budget and limited knowledge are big factors. Is there any chance the likes of forks and cogs etc are compatible? Thanks.
Most things on a bicycle are fairly standard and can be swapped between frames, but there are a few things you need to watch for:
Brakes, obviously you can't fit disk brakes to a frame without disc brake mounts or V-brakes to a frame without V-brake bosses.
Forks come with different diameter steerer tubes and different crown heights, threaded and un-threaded. Most MTBs made after about 1995 have unthreaded 1 1/8" steerer tubes, but you need forks with a similar axle to crown height, if you wish to maintain a similar steering geometry, so if your exchanging suspension forks they should have a similar amount of travel.
Seat posts come in a wide variety of diameters and obviously the seat post has to match the frame.
Bottom brackets have two different threads, English and Italian, nearly all are English now, and two different widths, 73mm and 68mm, most are 68 and modern external bottom brackets can fit either and are adjusted by means of shims.