BIG OLD WAIST OF TIME...... 748 is a dog, might bolt in maybe, but why???
If the frame you have is a rolling chassis, I mean complete, then find a newer 749/999 engine to put back into it, otherwise you will spend a boat-load of money to do it with a older-style engine, and it will be worthless when done.....I just recently acquired an 03 999 frame for cheap, and also found a 748 wrecked bike for cheap. Would all the parts from a xx8 bike fit on a xx9? I know that there are frame differences but would this work out for a track bike?