750 upgrade

It occurred to me that rather than re-ring a 650, I might do better going to the next displacement.

The easiest thing is swapping in a done 750 KZ motor, maybe. Is that a motor only proposition? Will it fit?

Another thought I had was;
pistons and cylinders, keeping everything else for now.

Hey it's only money, right?

Thanks in advance.

750 topend with 810 kit:evil:

Or a done GPZ750 (aircooled models only) motor

Add in a 810 kit, better clutch, oil cooler, shave the head, degree the cams, get in better carbs...

And away you go with tons of power and money sunk!


Plenty of good KZ750 motors you can bolt up for a quick, dirty, and easy upgrade. Only things I'd worry about on a low mileage motor is weeping seals, bad clutches, frozen timing advancers, rotten rubber carb-->engine seal.

It might be less hassle to just swap in the top end of a 750 engine (cams, head, pistons, the hole bit) if your bike is already a good runner. That way you won't have to worry about any bottom end trouble the donor engine might have.

Also, its a good time to change the camchain and make sure valve tolerances are correct.

I just reread your first post.

I would definately go the route of finding a donor 750 motor with low mileage rather than re-ringing your 650.

Probably cheaper and definately tons more power.