Engine replacement

[Sergio]

Hi, is it possible to fix a new engine (from gixer 750 for example or some other Suzuki 750-1000 cc) on Kat 400 frame with minor changes?

[Katgeezer]

Well....the basic answer is yes as it's been done. We have a guy with a gixxer1100 engined 400. Having said that it's a lot of work. However,I've got a GSX600 engine to go in a 400 and from my basic measurements it'll go in (just).
As I'm sure you're aware the 400 engine is tiny and there's not a lot of room in there. I personally think an oil-cooled gixxer750 will probably go in, it's just that I got the 600 real cheap.
I know your prices are pretty steep over there but you could fit a 600 with a big-bore kit (a bandit 600 can go to 840cc) but financially that would be expensive.

[Pedda]

You also mentioned 1000 cc engines. These are quite small, so maybe they fit better than the oil cooled lumps. But I don't know of anybody who did that job yet.

[lomsavage]

the 4/11 (its the orange one)

[bobster]

Harry had to cut, widen and weld extra metal to modify his frame to fit the oil boiler motor!

So not a straight forward job...........