Need help to ID engine year

[flyingace]

I have a spare 850 engine, probably a '79 or '80. It did not come with carbs, so no help there. Is there a way to identify the year of this engine? I'm trying to determine what pieces are and aren't swappable with my '83.

Thanks.

[bwringer]

A '79 engine will have screws for attaching vacuum gauges built into the cylinder head.

On a 1980 or later engine, the sync screws are built into the rubber intake boots.

[bwringer]

Also, a '79 GS850 engine will have a kick starter, and the later models do not.


Functionally speaking, the 1979 model also has points (instead of electronic iginition), a 12-pole stator, and the cylinder head is different to accommodate slide carbs instead of CV carbs.

[flyingace]

Thanks Brian.

I was told it was a '79, but evidence points to '80. It has elec. ignition, a tubeless type rim, no kickstarter. The vacumm outlets are built into the metal intake 'manifolds'? - intake rings that are attached to the head, but not part of the head itself. I wonder if this was an '80 engine still mounted with the older carbs.

I'm trying to determine if I can use the old head/valve cover on my '83 engine.