Please help me identify this 2 valve GS motor

[Jd Powell]

2 valve shaft drive GS motor. Crankcase ID: U701-103457 This is quite different from the engine #s I've seen on other GS's. Other oddities include 72mm bore in the 1074 block, but only 64.8mm stroke. Head has the asymetrical 19 bolt valve cover. Also the Ignition (Electronic) does not have a mechanical advance unit. Its not missing it just has a different kind of setup. The motor is not in a bike so the VIN is unknown. Any help would be greatly appreciated. I bought it as a spare for my '80 GS1000G. But it was missrepresented as a 1000.

[Steve]

Given those bore and stroke dimensions, it works out to 1055 cc.

You bought it for your G. Does it at least have a shaft output?


.

[Jd Powell]

Yeah itsa shaftie. I'm thinking maybe a 1000 bottom end with an 1100 topend. Though the weird ID # and funky timing set up makes me wonder.

[BassCliff]

If I'm reading this correctly...

Mr. Jd Powell,

According to the chart at http://www.gs-classic.de , the "U701-" denotes an '82-'84 GS1100G. If the frame # starts with "GU71G-C-" then it's an '82. "GU71G-D-" is an '83. "GU72G-C-" is an '82 1100GK. "GU72G-D-" is an '83 1100GK. "GU72G-E-" is an '84 1100GK.

You may want to see if I read that right. My German is a little rusty.

EDIT: Oops, no frame. Never mind.

Thank you for your indulgence,

BassCliff

[bwringer]

You know, a picture or three would really, really, REALLY help...

Sounds like you've got an '82 or "83 1100G engine there. If it was originally painted black, it's an '83.

It should bolt right in to your 1000G, too (as well as a GS850, if you have a spare one lying around), although the output flange where the driveshaft bolts on MIGHT be slightly different. Test fit the driveshaft and make sure the bolts go in before installing.

[Griffin]

You have an '82 1100G engine that someone has painted black at some point in its life. Your s.n. U701-103457 is a bit lower than my engine's s.n. of U701-104352. I don't think it's a 1000G bottom end, due to the ignition's lack of mechanical advance. My bike was assembled in December of '81. Suzuki's production runs usually went from about Oct. through late Aug./early Sept. the next year. I don't know if the engines were actually built earlier than that. I suspect they were probably about a month ahead of bike production, in order to ensure sufficient supply when assembly began.

Stock specs for this engine are:
Bore - 72mm
Stroke - 66mm
Disp. - 1074cc
Comp. Ratio - 8.8:1

[bwringer]

Most '82+ ignition rotors look like this, which I think is what you're describing -- the solid ignition rotor for an electronic advance:
(I've seen a few '82s with mechanical advancers)


From this page:

http://bwringer.com/gs/tdc.html

[Jd Powell]

Thanks guys for all the solid info. The motor is now positively identified as an 82 1100G. I remeasured the B/S @ 72/66mm. Looks like Ive got a bench power plant to build up while I'm trying to kill this one:-D
Any input on how the electronic advance works? Maybe use a Dyna 2000 ign with it?