Milky Residue On My Sight Glass.

[mikeee]

Hi, I'm Michael.
I'm hoping that I've posted this in the right section, sorry if i haven't. well I'm posting because when i first start my bike up especially in the morning, i get a milky residue on my oil sight glass, now i know that if the oil is milky then its more than likely the head gasket has gone, but the oil its self isn't milky at all, plus i did a oil and filter change about 1000 miles ago and the old oil was just very dirty . so i was wondering if this is residue i get on the glass is just some sort of condensation that occurs and that there is nothing to worry about, or if there could possibly be a problem with the bike (1999 ZXR400 L9).
Thanks in advance

Michael

[CaNsA]

Go for a nice 100mile blast on some twisty roads or hoon it up the motorway for a couple of hours.

You'll be reet

[mikeee]

Thanks for the quick reply, and yeah i will do
Michael

[Tirpitz]

It's nothing to worry about if it goes away after a good long run Condensation gets into the engine when it's stood, it's not hermetically sealed. When the engine gets warm it boils off and condenses again on any cold surface. If there is a film of oil on that surface the oil turns milky - that's what you are seeing. If you get the engine really hot for long enough the hot, moist air in the engine will exit through the breather and what will be left in there will be hot, oily air and all the milky residues will have disappeared along with the water vapour.

This is why short runs ruin engines - they just encourage condensation to settle all over the engine internals.

As CaNsA says, a good run will clear it. A ZXR400 engine won't get properly hot under 10 miles.

If the oil itself is a milky mess like frothy milkshake, that's when you've got a HG problem.

[mikeee]

Thanks for the replies CaNsA and Tirpitz, it makes sense that short runs encourage the vapor to settle, as this only occurs on the Sunday morning, the day after i drive a very short 5miles to work, whereas during the week i have a 21mile journey to school. but yeah went for a good long hour and half ride earlier, and the layer of white has disappeared .
Thanks Again

Michael