Re: more power suzuki
I know someone who fitted a racing exhaust from a XR2 to his 200hp 2 stroke, no idea on the make though.
getting the right prop could improve it.
there are also companys who can ramp up your engine. superchargers,air filters,advanced timing.
find a company on google who does this and find out what they can do with your engine, i have a feeling it's not cheap though.