No Oil in Sight Glass

[Jim R]

Hi - 1982 GS1100G - I have a very small engine oil leak and am waiting for the riding season to be over to change the gasket so I have been keeping a close eye on the oil level. Parked the bike after a 15 minute ride. Looked at the sight glass 10 mins later and it showed no oil. I mean zero. Left it alone for 90 mins. Checked again and still no oil. Bike ran fine and there was no indication of anything leaking more than the regular few drops. Oil pressure light functioning and turned off when cranking engine. Ran the engine a few seconds and shut off. Oil then filled up the sight glass. Anyone have any idea what happened?

[Nessism]

Is the bike on the centerstand while checking? If not it needs to be. Anyway, what you describe sounds like the oil over the sightglass. Check oil from a cold start, run for a minute or two, shut down and watch the level as it drains back to the sump. If it goes to the top of the sightglass you have the answer.

[Jim R]

Yes. Always on the center stand. I only park it on the center stand because I am frequently checking the oil. I'm not sure you understand what I was describing. After riding, the oil didn't drain back down. It showed zero oil even after 90 mins of sitting (on the center stand). When I started it briefly and shut it off, THEN the oil came back down and showed in the glass. I can't figure out where it was hiding.

[Rob S.]

I'm not sure you understand what I was describing.

I do - oil that's so clean you don't see it, particularly if it fills the glass.

In any case, I've frequently sat on the right side of the bike and tipped it toward me to see the oil.

[Jim R]

No. The oil has about 1500 miles on it. It is dark brown. I promise you. The glass was empty.

[storm 64]

What type of oil is in it? Conventional or Synthetic? Because that Synthetic oil is some mysterious stuff... 😉

[Jim R]

Regular Quaker State 10W40

[Steve]

Check the API seal on the back label. If the bottom half says "Energy Conserving", drain it and put something rated for a motorcycle wet clutch in there.

Not too many 10w40 oils have that Energy Conserving rating, but they are starting to show up.

Either way, most automotive oils are not rated for use in a motorcycle, mainly because a lot of the additives that make it work in a motorcycle have been legislated out of the oil. Some are gone entirely, most are greatly reduced, either way, it's not good in a bike.

.

[Gorminrider]

Very Peculiar,JimR! I havent got an 1100G; just a 650G and not sure how similar they are excepting the sight glass and MAYBE yours shares sump oil in the shaft's output secondary gears?...some bikes keep this oil separate, I think.

But on mine, it's a matter of not-much oil to show or not-show in the sight-glass so it's not much that's getting held somewhere..There's diagram in my manual of the oil's circulation...which might help inspire someone's idea..though, again, this isn't your bike...still, it'd have to be above the sump screen if it's getting held back and that's where my imagination ends I'm afraid...the vanes of the pump don't seem likely-they can't be such a tight fit ..the bypass? is a springpressure thing...hmmm

I hate the sightglass altogether. It's there because the design puts the clutch right under the fill hole and a straight stick can't be inserted but I wish they'd made a better effort.
oilcirculation-small.jpg

[Gorminrider]

Do you have an oil-cooler on this bike? that would do it maybe.

[Jim R]

nope. 100% stock.

[Cipher]

15 mins ambient temp? oil never reached correct operating temp.
try it with synth be amazed

[gbw]

I had this issue on and off with my 77 GS750. Sometimes it wouldn't show oil on the sight glass. I always made a habit of checking it 5 minutes after a ride. It would always show up then. Not sure where it went to hide, but there was always enough oil in there.

[gustovh]

Happens on occasion to both my 1100’s and my 850. It always fills back up with an engine restart of about 30 seconds or so. My theory is that it is being held in the top of the engine some how.

V

[Cipher]

the volume of the passages above the pump not draining back
a good thing probably
is oil light off with key on when oil is hiding? some senders are at the filter cover some behind cyl bank