thanks for the response, i might actually pull out the one i bought off ebay, which when fitted still blew but was in worse condition than my old one so put my old one back on, and try sealing it with the silicon and give it a go for a while? so if it improves any?
Is it definitely the end can that's blowing ? It could have rotted out inside which would also give the rattle, I have dozens of standard cans. Also just get the bike running and get it warm then feel for the blow by running you hand around the pipe - WITHOUT TOUCHING IT. if the end can is rotting out then its a sure sign that your downpipes (if original) are not far behind just feel underneath on the 4-2-1 collector and make sure it's not blowing there.
Owner of Motorcycle Republic, Specialist in unfucking things that others have fucked up.
Deffer666 - yeah definitely blowing out of that gap where the black pipe goes into the end can. i have had a look over the down pipes and although not in the best condition they are pretty good.
The end also looks in great condition just this blowing from the gap in my picture. checked it last night before riding home from work and again when i got back.
With out actually being able to take it apart its hard to tell whats going on inside, although as i said before i know pretty much nothing about engines or bikes as such, so any advice or info is always greatly appreciated. bearing in mind it is a 98 model so its getting on a bit now and no idea how many parts are still original.
Have a look here as there is some extra info on rotting cans and a picture of inside
http://foc-u.co.uk/index.php/topic,15938.0.html
I don't do rain or threat there of. dry rider only with no shame.