Engine swappage!!

Good day folks

I have ridden my little kwakker all over Norway this summer, and despite good times and contagious smilage everywhere I've been, her heart just can't take much more.
Stripped the engine this winter, new 750 cams, gaskets, valve guide seals, the works.
Silly enough to disregard changing rings at the time though.

Anyhow, there is loads of smoke on startup (worn valve guides?) which disappears after warming up, and zero thereafter.
Oil usage is unfathomable, emptying the sump after hammering it, reckon it's the pressure in the crankcase blowing oil through the engine seals (leaks all over, not a drop when standing). I will fab a few extra vents in the rocker cover to try ease this so I can make the 23 hour ride home, but it's not looking great.
PSI across cylinders is 100-130-150-145.

What I would like to know is if a 750- 1000cc powerplant could fit easily in the frame, I am not after monstrous power- more interested in nimble handling, but what are the weight differences like? What other aircooled engines are worth looking at- mpg and power wise?

I was planning initially on doing the 750/650 hybrid, but the head on my machine looks to be very tired

Any tips more than welcome!

I am guessing you have the 650. If so then yes the 750 can be fit into the 650 frame.

Sure,

But I'd like to up the ante a tad, maybe go with a 1000.
Yet there doesn't seem to be info on engine weights around the net..

Do a search, someone else on here recently was looking into the same swap.

you can put a 1000 engine in a 650frame but you will have to spread the downtubes to allow the sump to drop in also it,d be a good thing to stiffen the whole frame up with some braces here and there but it is do-able -look up post entitled better than sex it might be of some use

when i said downtubes i meant the two cradle tubes at the front need to be spread

Hobo, the 750 was a bored out 650, therefore they are basically same engine with same external dimensions, and mounting points. A direct swap. The 900-1000 was a different earlier engine with slightly different architecture, so dimensions are not same and would require frame modifications. That's what they are trying to tell you;