Is there any difference between the old 4XV ones and the newer 5PW ones.

I've got a 4XV one fitted to my 08 R1, and it seems to still be very loud at high RPM, and am worried it will fail even a 105db trackday.

Are the newer ones quieter?

Cheers

The standard 4xv can is considered to be one of the quieter bike cans out there. It is quite restrictive in standard form and many have had the baffles removed and made them straight through. Are you sure it's standard? mine went through iva with one on, think the figure was 97db. Mine is a 4xv lump tho. My post iva can is now straight through with accoustafil and it is a fair bit louder.

Not sure on volume differences but the 5pw Can is titanium and can be tricky if needing adapting to fit.

It's possible, how would I check? Will I need to drill out the rivets and pull it apart?

Yes pop one of the end caps off. I would say if you think it's 105+db then it's definitely been messed with.