Questions about 650 motor

[7981GS]

Might be considering another project.

What size are the piston pins?
Do 650 and 750/850 barrels share the same stud spacing?
750 head work on 650 motor? (oil passages the same, etc.)

TIA,

Daniel

[TheCafeKid]

Don't think they're going to be compatable with 750/850 stuff at all or someone would have done it by now...
There are "big" bore kits available, however I think you'll find the stock 650 to be more potent than you might think. Weighs much less than the 850 and puts nearly the same power to the ground...

[Guest]

The cylinder spacing on the 550 and 650 are the same but different to the 750/850.

[7981GS]

Next question then...

Will a '79 850G or '81 1000G fit in an '82 GS650G frame?

Daniel

[1_v8_merc]

Don't think it will work.

The Large Inline's are about 21 inches long-frame to frame
The Height is about 18Inches Plus-for the motor

You will be easily hitting the gastank at 18 inches on the 82 650G
Guess you could raise the tank?

You might be able to cram the motor in there, but the mounts might differ slightly.

I'm not sure what your fab skills are?