While going through whole-bike rebuild on two new-gens, which started out as just changing oil in front-forks of my race-bike, I found pile of exhausts. Figured I'd document them.
FACTORY OEM EXHAUST
2.5cm = diameter at exhaust port outlet
52cm = left header length
45cm = right header length
3.5cm = diameter after merge
3.5cm = diameter just before muffler
Factory header consists of straight pipe that goes directly into exhaust-port with flanges welded onto it. Supposedly merge has mini catalytic converter. Pipe diameter after merge is 1.96x cross-sectional area as individual header tubes. A perfect match for 2x flow. Pipe stays same diameter all way to muffler