What kind of oil.

[Anonymous]

I recently bought a 1983 GS750T and would like to change the oil in it. I don't have a manual for it (finding one for a 1983 GS750 is not the easiest thing). What kind of oil and how much should I put into the bike?

[focus frenzy]

a motorcycle specific oil would be best, especialy a motorcycle synthetic oil, but regular automotive oils will work fine as long as it is not a energy conserving rated oil.
modern automotive oil has aditives in it for reducing friction and this is not compatable with motorcycle wet clutches, it causes them to slip and fail.
this aditive is in almost all 10w40 automotive oils, you will need to look at the bottle, oils containing this aditive will have a star like emblem printed on the back or front of the bottle.
most 20w50 oils don't have this additive, but depending on the bikes mileage and you location 20w50 may be to heavy a grade oil.

Valvoline and a couple other big oil companies produce oils formulated for use in motorcycles, Autozone carries valvoline motorcycle oil as well as mobil 1 synthetic for motorcycles.

auto parts dealers who don't have it should be able to get it for you, and it would be WAY cheeper than getting your oil from a motorcycle dealer.

some people do run regular automotive oil with out any trouble but most do have problems.

[whodatpat]

You did it now. This link should provide hours of reading. If not then just search on oil. You can read this stuff for days. Basically do what the manual says, or what is stamped on your engine. Keep it fresh. Change it as often as you can. These bikes predate anything synthetic, so the Dino Juice should be fine, and cheap enough to replace twice as often.

http://www.thegsresources.com/_forum/viewtopic.php?t=11855&highlight=synthetic+oil

Patrick

[Pete's GS]

Hey, that link was a rip! Anyways, I use 20W-50 Exxon in my 1980 GS550E. $1.29/litre. Bike runs and shifts just fine. Less seepage and oozing from the valve cover gasket (which I need to replace but I can't get the %#@*^ off) than with 10W-40. I also like full-synth Castrol Syntec, which I use in my 1980 XS650. That bike is notorious for having dragging clutch plates but I get good shifting with the full-synth Syntec and regular cable adjustments and lubes. Otherwise, honestly, GS motors are built like brick &$#@*houses. Just change the oil every 1000 miles and ride the bike into the ground.