Idle, bars and airbox removal

Might as well lump my three considerations into one;

I recently rejetted and put on new pipes.
Now she won't sit idle without the choke for more than a few seconds before cutting out.
I went from stock mains to 130 and changed nothing else, any thoughts?
(Went for a ride last night and she seemed to hit 90 and get really grumpy, the lad behind me said it sounded like a scream more than the normal roar, felt like I hit the limit of that gear but I'm sure I'd gone up to 5th..)

I'm also looking at some 8" chumps and am looking either for whether or not I'll need new cables, or.. Well, where to get new cables. Not had much look on the few webstores I know of! (alterate manufacturer parts that may fit instead?)

And finally.. I want to get rid of my airbox but have a mate who can play with steel.
I was wondering if anyone had built up their own brackets and boxes to do it and whether they had measurements handy? I'm not the laziest lad in Wiltshire but stripping the back of the bike down so I can make some cardboard mock-ups isn't how I planned my month off!

Thanks for looking!