finally, I've fitted a right looking exhaust to my TT2 - it came from Mario Sassi
http://www.oldracingspareparts.com/twin ... tt600-tt2/and fits nicly with only minor adjustment
With some internal modifications I was able to obtain a sound pressure level of 103 dB(A) @ 4500 rpm at a distance of 0.5m / angle of 45° at the exhaust opening.
Funny thing is, that the exhaust is still street legal (theoretical) for my motorcycle but not allowed on most of the race tracks
Cheers
Wolf