'05 R1200ST - do I need a new oil sight glass ?

'05 R1200ST 93K miles. I changed the oil recently and a few days later I noticed that the oil level wasn't showing in the sight glass. I thought it was because of the nice new clean oil. But now after a few hundred miles it seems like the new oil should have darkened a little. I am now pretty sure that I am seeing only the gold-ish colored back of a dry sight glass. I loosened the drain plug bolt and confirmed that there is oil in the motor.

Looking around the Forum I see lots of threads about leaking or weeping sight glasses, but nothing about a completely dry sight glass with no oil level showing in it.

So do I need a new oil sight glass?

TIA.

ranbush said:

'05 R1200ST 93K miles. I changed the oil recently and a few days later I noticed that the oil level wasn't showing in the sight glass. I thought it was because of the nice new clean oil. But now after a few hundred miles it seems like the new oil should have darkened a little. I am now pretty sure that I am seeing only the gold-ish colored back of a dry sight glass. I loosened the drain plug bolt and confirmed that there is oil in the motor.

Looking around the Forum I see lots of threads about leaking or weeping sight glasses, but nothing about a completely dry sight glass with no oil level showing in it.

So do I need a new oil sight glass?

TIA.

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No you do not need a new sight glass. Either the oil level is too low so no oil is showing in the sight glass or the oil level is so high that it fills the sight glass and appears there is none. The first thing I would try - with help from a friend or two - is to tilt the bike to both sides while observing the sight glass. Leaned toward the glass oil should appear if it is low. Leaned away the level should drop in the glass allowing the top of the oil to be observed

If for some strange reason this fails then I would drain the oil into a spotless clean drain pan and measure it. I would then add the correct measured quantity back until visible in the sight glass.

PGlaves said:

No you do not need a new sight glass. Either the oil level is too low so no oil is showing in the sight glass or the oil level is so high that it fills the sight glass and appears there is none.

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Thanks, Paul. You are of course correct; I had it overfilled. Adding the right amount of oil makes the sight glass functional again.

I have always thought that BMW started using a sight glass instead of a dipstick to make sure that their customers have to get down on their knees on a regular basis. I have an extendable inspection mirror in the tank bag on my ST and one on my K75S, but since the sight glass is down so low on the motor, the light has to be just right to be able to see the level of oil in the sight glass.

Thanks again.