Keep your 620 and uprate it to an 800 as you will lose less than buying another bike Paul.
Youd need barrels & piston and maybe an upgrade on the computer tho you can prob do this with a power commander. cheaper way to go mate.
I dont know what happened to the bb kit that geoff used at the beginning of last year went to but that would be ideal for your needs
you could even try & get an 800 engine (or a 900 for that matter) & swap it in and flog the 620 engine to a dd'er and get your dosh back.
can also buy fairings to put on and off as the mood takes you for trackdays, sportsbike one week and monster the next
hope this helps muddy your waters even more
