I reckon you could probably use something like VFR400 NC30 springs (or look for a set of complete forks - although you will need the bigger discs too then) to stiffen the front a little. A little more/heavier oil than standard will probably help too.
You are basically running into an issue us "fuller figured" types have with import suspension... it's just that your motor is putting the stress on the forks rather than our body mass!!
Try mixing 10W and 15W fork oil 50:50 (12.5W), and adding a little extra over stock.
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Andy.
NSR-WORLD.COM
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