Engine oil level incorrect - mysteriously disappears, then reappears.

[Guest]

I've had a 1979 GS850 for about a year, and recently it has been exhibiting a strange behaviour. The oil level stays at the full line consistently over weeks, then disappears suddenly. No leaks. When I put more oil in and ride, the next level check is way above the full line.

Note:
I'm checking on level ground, and always when the bike has sat for several hours.

I read an old forum that BikeCliff wrote about a similar experience, but it doesn't explain the phenomenon:

https://www.thegsresources.com/_forum/showthread.php?108671-Oil-Indicator-Question&highlight=oil+level

Is it wise to get an oil pressure gauge for these bikes?

Thanks.
RJ

[redbobrob]

Accidentally deleted the previous post.. here's a great reply from
Nessism..


Here is the message that has just been posted:
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The oil level should be measured per the method detailed in the factory service manual: cold engine, bike parked on level ground and up on the center stand, start engine and run for about one min., shut down engine, wait one min. or so and then check the level.


Most of the time oil level inconsistencies can be traced to an inconsistency in the way the level is measured.


PS: your bike already has an oil warning light. That's all you need. I'd skip any accessory gauge because it's more likely to cause a problem than prevent one.
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[TxGSrider]

Ive wondered what the effect of my little oil cooler has on those measurements.
It looks like the factory installed coolers have the fittings on top to, I assume, keep it from running back into the engine, but the little aftermarket one on my GS has the fittings on the bottom.

[Steve]

If you do decide to get an oil pressure gauge anyway, make sure you have one of the proper range.

When you fire up the bike cold, you <might> see 10 psi. Warmed up and going down the road, maybe 3 psi.

These bikes work on volume, rather than pressure, due to the roller bearing cranks.

.

[redbobrob]

Thanks for the advice.