Exhaust Diameter

[hackers2r]

I am looking at having a custom exhaust made for my S2R 800 but have an important question.  All the systems for my bike are 2-1-2.  If I were going to do a 2-1 system, what would the optimal size for the pipe to be?  My natural assumption is that since both header pipes are 45mm, the collector pipe should be 90mm.  Am I correct? Close? Completely wrong?  Thanks.

[Raux]

if something is to have the same flow suppose it would have to have the same cross sectional area... right?

Pipe Diameter   # of Pipes   Cross Sectional Area   
45mm                 2   3179.25mm2
60mm               1   2826.00mm2
62mm               1   3017.54mm2
63mm               1   3115.67mm2
63.63962mm   1   3179.25mm2
64mm                1   3215.36mm2
65mm               1   3316.63mm2


Not sure you'll find a 63.63962mm dia. pipe... but it would be the same cross section
this is just a pure mathematical approach, i'm sure in practice it is much different.

[hackers2r]

Well that solves that question, mathematically speaking of course.  If anyone else has any insight, it would be greatly appreciated.

[hackers2r]

In addition, there was a link to a crossover pipe calculator posted on here once.  Anyone have it or know the proper distance for this motor?  Thanks.

[greenmonster]

Spaggetti systems, like SilMoto f e, has same diameter in crossection as rest of the tubing.

[hackers2r]

An additional question, does anyone have the inside diameter of the exhaust port on the S2R 800?  Thank.

[Howley]

You do if you have an S2R 800 and a ruler.