GS1000 Motor in a GS750

[knotscott]

Hi gang - A GS1000 motor popped up on CL for $150. Condition looks a tad rough from the pics, but the price seems reasonable. Gonna look at it tomorrow.

If I pick this motor up, how big a deal is it to swap motors in my GS750? Also, are there any "gotchas" that I should be looking for on the used GS1000 motor?

[Steve]

You have a '79 750, which is a plus.

If the 1000 engine is from a '79 or older chain-driven bike, it's pretty much a drop-in.

If the 1000 engine is from an '80 chain-driven bike, you will have to be sure to also change the carbs and the ignition systems.

If the 1000 engine is from a shaft-driven bike, forget it.

.

[knotscott]

Thanks Steve. The GS1000 motor is from a '79. Not sure if it's from a chain or shaft drive, but will be sure to find out.

[Steve]

If it's a '79, it pretty much has to be a chain.

Unless it was one of the early shafties that was MADE in the last part of '79.

The 1000G (shafty) was introduced for the 1980 model year, but some places claim the year of the bike by the production date, and the first of the '80 model year production might have come down the assembly line as early as August or September of '79.

.

[knotscott]

Owner confirmed that it is chain drive. I'm going to look at it tonight, and will try to find out more about it's history.....like why it's out of the bike, when it ran last.

Another question - Will the Vance Hines headers on my GS750 bolt directly on the GS1000 motor, or will I have to modify them?

[unfocused]

It's not plug and play... I'm in the middle of this swap. Foot pegs, motor mounts, #whyamidoingthis LOL

10.16.2019 775.jpg

[RichDesmond]

I guess my question would be, why bother??
The suspension and frame on the 750 aren't any better, and the weight difference between the two bikes is largely in the engine.
Be far easier (and probably cheaper) to just buy a GS1000.