I haven't even delved into it yet.
It will require 61mm pistons. I can have mine made in 61mm but with the dome they'd be about 60,000:1 compression.
Evidently some Euro spec Kawi pistons come in 61mm with 14mm wrist pins. I think they are the right deck height too, or close anyway. My castings may have the meat to take the dome off, I guess they could be done up in 61mm then I could just mill off about a quarter inch of dome.
Jugs will have to be hogged out for new liners, cases bored to take the new liners. Something would have to be done to narrow down the chain tensioner so it will fit between the cylinders. You'd have to find 5mm in there somewhere. It's possible CB200 jugs would have to be used, I don't know if 175 jugs can take liners 5mm larger.
Different wrist pins would probably be needed (longer), and maybe some crank work to balance the heavier pistons.
Top end HP wouldn't increase too much without good porting and oversize valves but you'd pick up quite a bit in the lower rpms.
Yeah it should have some good torque.
It would be for sure worth a two or three seconds off laps times. And good to be competitive in 250gp. But if someone wanted to keep up with a bike like Ruffo's Ducati, or Phil's Bultaco it would require working the whole motor.