A Racing setup is a bit different in that the bike stays at a much higher rpm. Open headers will allow for more horsepower at very high rpm ranges. However, for daily riders who need torque, the 2-1 setup is typically better. As we live in that 2500-4500 rpm range. Open headers rob low end and mid band power a bit.
Could you expand on the stepped theory? Wouldn't expanding the space the exhaust flows into, cause it to slow down? Seems like you'd want the exhaust moving as fast as possible.
Yes, but no. The stock header mashes the front and rear headers together into a single pipe, but it’s not designed to function the way a collector on a 2-1 system is. We believe the stock headers are only designed that way to give a place for the catalytic converter, and performance doesn’t really enter into it. Also, routing of the stock headers makes the rear header significantly longer than the front, leading to an imbalance of backpressure. To really make power, especially torque, a collector needs to be able to provide a quick path for exhaust coming out of the motor, while also equalizing backpressure.
Why do most True duals come from front cylinder down under and out the clutch side and the rear comes out and down Throttle side and only a few put the rear cylinder to the clutch side.
If you’re looking at back pressure, why not the lollipop solution to equal dual exhaust coming out another words the pipes are equal if you stretch them out the same amount right to the same spec as those sides get your look still, but adding a lollipop sells them you get your back pressure by placing the correct one into it I wonder how that would work to make the two doors give you what the 2:1 give you?
We don't recommend "lollipos" or any kind of inserts. In theory, they may help provide back pressure but they have a negative impact on exhaust scavenging and are also prone to coming loose and falling apart.
True dual is alwayse the better way to go, It removes more heat, each cylinder breathes better and every real race bike runs straight headers for a reason. if 2-1 made more power thats all you would see at the track