Bike re-build question

Well not sure what bike / components you have now and what frame you are looking to transition to.

I just did this recently, and mostly everything was able to transfer to the other frame fairly easily.

The only things that had to be replaced, was the chain and the cables / housings for the brakes and derailleurs.

Mainly you need to make sure the bottom bracket is compatible with your crankset. There are different types such as the BBright, BB30, BB90, and 68mm Threaded (common). So you would want to match what you have optimally.

http://www.parktool.com/blog/repair-help/bottom-bracket-standards-1...

Your steering setup should transfer over, although you probably will need a different stem, also the stack will most likely need adjustment.

Brakes may work ok on the new frame, but depends if the frame is for standard side pull brakes or whatever you have. The mounting pins may need replacing since the frame thickness might be different.

Derailleurs, front derailleur most likely has a mount, and so does the rear derailleur. So those should transfer over.

The main issue after getting the parts over, is to (1) cut the housings, (2) run the cables for brakes and derailleurs, (3) alignment of derailleurs, and (4) brakes.

Then you'll have to adjust the bike for proper fit.