One of German tuning shops offers 5-staged tuning for engine, do not rememeber by heart but something like stage1 +10 bhp, stage 2 another 5 bhp on top, then another 7 bhp and full-scale is 130 bhp and 125 NM at rear wheel.
Chassis are not such a problem if you put some decent upgrades on, like front from Blade, JMC or Mechmatex swingarm or just bracing, heavy-duty mount for swingarm, and reat shock abosrber need change anyway.
Of course you can not expect it to be superb, but it'll cope - there is a lot of exaggeration about flexibility of chassis....while ago some tests were published where old OLD bikes chassis rigidity been compared to new New, and they found that difference was way less than manufacturers claim. Of course they did not compare Blade to VMAx, but old blade to new, old ZZRs and ZX to new etc.
I spoke to guys that put their RSVs and Hawks through this German tune-up - they say this company can even sell you complete ready-to-roll engine..but noitice that they do bore out cylinders to something like 1120 cc but: they even giving you 1 year warranty on their work!!!
Now - only problem is to find that URL they sent me...
Ah, here we go: http://www.thiel-motoren.de/Start.htm