550/650 and 750/850 interchangeablity?

[Guest]

I see several posts about putting a 650 top end on a 550, and some about putting a 750 top end on an 850. I'm just wondering why I'm not finding any about swapping between 550/650s and 750/850s. Are the bore centers different (the carbs all seem to have the same spacing), or are the studs at different locations, or are there other factors preventing this from being a relatively easy swap between those models, apart from possibly relieving the crankcases to fit the larger liners in a stock 750 or 850 block? Someone out here must have tried this at some time - what did it take to make that swap work?


Thanks in advance!
Mike

[Big T]

Actually, one puts a 850 top end on a 8V 750.

The smaller motors won't swap with the larger motors

[Nessism]

The 750/850 are a much larger engine than the 550/650. Totally different so parts between won't swap.

[Steve]

True, the 550 through 850 all use BS32 carbs, but the spacing is different between the two center carbs.

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