To shorty or not to shorty...

[dougl]

The OEM #1 has a curve, but you are correct in that #2 & #3 intersect at 90°.

Nearly all right angles. Maybe the curve on #1 helps push exhaust from #'s 2 and 3 even though they are right angles. It may not be the most efficient but it couldn't be ridiculously bad. The thing works pretty well.

 

[IMFASTTOO]

Nearly all right angles. Maybe the curve on #1 helps push exhaust from #'s 2 and 3 even though they are right angles. It may not be the most efficient but it couldn't be ridiculously bad. The thing works pretty well.

THEY use that exhaust to govern the power output and detune the BIG ROCKET to suit the average V twin cruiser owner who wants to step up for more power ,better brakes etc and they want the bike to be user friendly for the new riders that are coming off a 60 HP slowpokes

 

[barbagris]

Even a move to Jardine headers (which are (I accept) far from perfect) improve flow - it's a tangible difference. Proper headers ( and I like the sexy curvy look more) will certainly improve things.

One point that's not been mentioned. Whilst pipe effective length affects WHERE max torque is delivered - the Volume of the system affects how wide that band of torque is.
Shorties will almost always make the amount of torque FEEL more tangible because it's a peaky-er curve.
I have THUGS fitted on the end of Jardine headers - these flow well but are a bit short.
Fortunately though they are torque-y right where I generally ride - rpm wise. They'd be better a bit faster (more rpms) - but then my licence would be at severe risk.