http://www.thebikerweb.com/Blog/Entries/2010/5/7_Bio-Diesel_Harley_Davidson_Fatboy.html
Sounds a bit like an almost-beefed up Ford Transit. Certainly wouldn't want to hear that while riding.
This is Larry Spiderman Mcbride the fastest biker in the world on his top fuel bike.5.7sec
Him again on the world's fastest electric bike he build.7.5sec not the same without the noise.