Which of two to rebuild/merge? - 1983 750 E and ES - Engine and rebuild questions.

[Andrew Vanis]

Which of two to rebuild/merge? - 1983 750 E and ES - Engine and rebuild questions.

Am wondering which engine/frame to concentrate on from two 83 750 E/ES bikes I got with the idea of making one good one out of. (see signature line)

1983 GS750E - bought in 2016 as a rough runner to use while rebuilding 81L and then to combine with ES to make one good one
1983 GS750ES - bought in Toronto in 2015 on a lark as a non-runner, missing front cowling and exhaust - If you have a 1983 750ES front cowling let me know! Blue would be nice

Engines – How do I determine which engine to focus on?

The ES 35K KILOMETERS (22mi) was raced in the past and sat for more than 5 years. I have not even attempted to start it.

The E 27k MILES (43km), though technically a runner, I can tell was treated hard….and it has pods.

Body – Which frame? What considerations around this?

The ES is from Canada and I did all the correct paperwork when bringing it into the country.

The E is local and I have title.

Thanks in advance for the advice,
Andy

[Carter Turk]

A friend had a beautiful W/R ES. There's been one on CL here for $2500.

Not sure if E frame has mounting threads for ES front fairing and possibly lowers if it's a Canadian EF.

Given the choice I would prefer using the ES/EF frame, so that if a front fairing turns up in the future it could be mounted, but run the E fairing in the meantime.

[kingofvenus]

E's had the fairing mounting lugs. The fairing bracket on that ES looks very bent. Use the best parts of both and save what you can for spares or, tradebait or sell...

[Sam 78 GS750]

Use the best parts of both and save what you can for spares or, tradebait or sell...

^^^^ This right here. I'm not sure if the engines are different between the E and the ES. If they're the same or have interchangeable parts, I would combine the 2 engines using the best individual components from each. Tear them both down, and use the gears in the best shape (down to 3rd gear is better on this one, but fourth is better on that one), the head with the best looking valve seats, etc.
...unless you weren't looking to tear into them that deep. In that case just try to get them both running as well as you can before you tear into them and pick the one with the least issues and use the other for donor parts that are an easy swap over.