I took my XT600e to the Circle last Sept/Oct and it was pretty cool to tick that one off, although not a major adventerous trip but still pretty cool!
I got the ferry from Hull to Stavanger (overnighter) and basically headed straight north stopping off in Bergan and Mo-I-Rana for hotels etc. Be aware EVERYTHING is expensive in Norway! Some campsites wanted 25 quid to pitch a tent, 40 quid for one of the little 'huts' and everywhere was 7+ quid a pint!! and no selling of alchohol in supermarkets after 9! I suggest to make freinds take a couple of bottles of the hard stuff and you'll become really popular! The ferry unfortunatly drops off late in the evening so it can be a bit daunting turning up at night with no campsite for miles. I pitched my tent at the first available 'field' out of town and set off proper in the daylight.
As for bikes, anything with two wheels will be fine as the roads are good all the way up to NordKaap, the most northern point of Norway and the scenery is beautiful and very similiar to the Highlands of Scotland. It pissed down for a couple of days and raged with myself for not taking a rainsuit, the heated grips came in handy and the iPod was a godsend as apart from the lovely scenery and the odd Elk there's not much else the further north you go. There's quite a few Roll on - roll off ferries you need to take to get north at a few quid a time and the longest tunnel in Europe (27kms ?) which looks cool as heck inside as it's lit up like an ice 'palace' inside. Some of the other tunnels were closed due to roadworks but made the trip as the views were spectacular from the tops. If you like your scenery mate, you'll love it!
If your just going to the Circle, I suggest you stay in Mo-I-Rana which is 100+Kms south of the 'dotted line'. As I left my luggage in the hotel and rode the bike up, did the touristy thing and headed back. There's a couple of good live music pubs there.
The 'Circle' hasn't really got much there apart from a couple of signs, a tourist shop/cafe and the wooden dove (?) statue so I bought a keyring, sticker for the bike and took a few pics. I returned via LilleHammer and Oslo to the ferry at Stavanger.
You might want to send an email to the "Norweigan Community" as I had a good response form both Norweigans and expats who were looking for a good ride out or offering advice and sometimes a bed for the night (thanks guys!).
If you've got any questions then email me firstname.lastname@example.org
'Security is a product of one's own imagination, it does not exist in nature as a rule, life is either a daring adventure or nothing.'