Synthetic oil in a 78GS 1000

[Pete Logan]

I did however leave the Amsoil in the transmission

Dan.

Slightly confused. If you still have the Amsoil in the transmission, why would it be the culprit for hard shifting ?

Pete

[Canada Dan]

I hope I didn't make a fool of myself here - I'm guilty of that from time to time, but I think the clutch runs in engine oil...

Dan.

[Pete Logan]

If it's the same as my 82 GS750E, it does. Which is why I was slightly puzzled by a reference to 'leaving the trans oil'

Pete

[Canada Dan]

Ok, so I'm confused now.

I should say at this point if it isn't already obvious that I'm not much of a mechanic.

The way I thought the bike was configured was engine / clutch in one section. Transmission by itself (drain accessed by removing the cover on left side) And the rear-end by itself.

So am I messed up with the what I think is the transmission? Maybe what I think is the transmission is something to do with the front end of the shaft-drive?

To be honest, the bike works so well that I haven't taken the time to learn some of this stuff.

Dan.

[redliner1973]

Engine/tranny share common sump. Both use engine oil, both are serviced at the same time via the oil filler hole on the right side of engine. The 'middle' drain plug on shafties contains 90w Gear lube and lubes the secondary gearing system (what you refer to as the "front end of the drive shaft'). Finally, the differential, located on teh rear wheel assy, also is lubed with gear oil. do NOT use regular motor oil in the secondary or differential assy.

[Canada Dan]

Thanks guys, long way around this I guess. Bottom line is once I went back to conventional oil in the engine/transmission the hard shifting went away. Sorry for the confusion.

Dan.

[Pete Logan]

I was just as confused as you, Dan, being totally unfamiliar with the GS1000 series

But it's all as clear as mud now

Gotta get me one of them shafties

Pete

[Jethro]

So yes, the mineral based oils DO break down faster than synthetics - this has been proven in thier molecular structure alone.

100% correct statement here propflux, couldn't agree more. Synthetics definitely resist break down at higher temps than mineral oils- temps that conventional internal combustion engines never, ever encounter.