Potential 650 c engine swap?

I have a 77 650c that has been sitting a while (years). To get it running I think a rebuild is in my future. I was wondering if swapping the engine would potentially be a cheaper and easier solution.

Assuming my theory is correct, what years/models 750's will fit into my frame without modification? I did a quick search in this forum, but didn't find the info.

Nobody? Is my question a silly one? I assumed I could swap a 650 for a 750. I realize I may be trading one set of problems for another.

Should I just dive in and see how bad the situation is? I am a bit leery about doing engine work. I am somewhat mechanically inclined, but by no means a gearhead.

If the engine is just seized at the piston rings do I need to pull the pistons or can they stay in place after I pull the cylinder block?

What is a decent price for new cylinder rings?

Thanks guys.

Why not dig in and learn a few things while amazing yourself at your resolve and powers?

Good point. I guess I need to grow some cajones.

Does it make any sense to stick with 650 cylinders?

I can put a 750's cylinder block and head onto my bottom end can't I? If that's correct, what model years mate up with my 77?

What is involved in making that switch?

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I am pretty sure that reborn650 did this with his. I think he got 750 barrels bored to 810 and I know he used his original 650 head as I saw it one summer evening in his garage and remember he had the 650 cam chain rather than the hyvo chain used on the 750.
That was quite the bike - a 650 with 810 displacement. I cant remember what he did for carbs. He may have used the Mikunis from the 650 and jetted up. I can remember velocity stacks. He has'nt been here in a while. HOpe he ws'nt arrested. That thing was a screamer
Try a search. There was a big thread on this about 2 years back.


Do forum search on "reborn650" to find links to some good threads related to this subject.

Good Fortune!