how to damp a racing exhaust already fitted with a DB killer ?

[jihem]

Is your GB breathing free? Try to temper that sound first. Put some Unifilter or Pipercross filters (or alternatives) over the rampipes. Try to minimize that intake sound first.

 

 

yes, it has K&N filters as the engine wasn't breathing well enough with its airbox (the frame) with the Scola cam.

This said, it's obvious most of the noise comes from the exhausts

 

 

 

By the way, I don't think you got the way of measuring right.

They will use the new FIM method. db-meter is 2m away from motorcycle and you will have to rev it up from idle 'till red and back to idle! That is what the organisator says.

If they do it the way you assume there will be a tolerance of 2,9 db.

 

nope, the way we mesured it is unfortunately acurate. There's a 5000 rpm limit for 1100cc twins, it doesn't have to be run up to red.