i am riding rvf.....
micron is gd for 400cc bike caterory and some higer cc bike,
the muffler when slip onto it,the bike setting also must be done to suit the muffler,i
think yr friend just slip on the muffler and never do setting for the muffler and thats why he will heard sound but no power,
with proper setting of the bike and the muffler
,the bike pick up will be much faster and the sound is sweeeee
.....when high gear at high speed then drop down gear
,,,there will be like a pong,pong,pong like back fire like that
songzzzz..i saw a 954 also use micron
,,,,,the sound,,,sweeeee.....
ask yr friend did he do anything before putting on the micron muffler??
did he redo setting and change main jet and some other things??
if not,even u put also not much use