I didnt use silicone, you dont have to but you do get a better seal and it stops air leaking back into the exhaust if you do, which means that your bike wont pop as bad on the over run when you shut the throttle.
I've got a curvy SV, so I dont know if the fitting instructions will be the same, I'll wheel the bike out the garage and take some pictures for you, I'll need to wash it first as its filthy
