We always used rockwool for the 540 and 580 KTM(the green insulation wool ) that got us past the Decibel meter in Europe and worked a treat . Most others did the same ( exept a few trendies ) and never hade a problem to this day .
That reminds me of little Hans . He was selling apple seeds in the street . 3 for a Dollar .The Teacher walked past and said " What are you doing little Hansi ?" " I sell apple seeds , they make you smart " was his reply. "Well I will take 3 then " the teacher said , paid and walked a few Meters chewing the seeds.
He then turned around and confronted the boy and said " I think you ripped me off , I could have bought a kilo of apples for that money" " See " little Hansi replied " its already working !!!"
I think that goes for a few things in motorcycling ......
