2011 YZ450 White smoke from oil breather

I always get good answers here so i'm asking before i take it to a shop. i did search the threads and didn't see anything close enough to convince me it's my problem.

Did an oil change this morning and took the bike to the track. noticed white smoke coming from the oil breather hose. must have just started cause i was following the bike (this is my sons bike) and it was very noticable. It is not a big cloud but just a small puff so to speak when he is on the gas. we let the bike cool down and checked the radiator fluid it was still very visible but a little low. the oil shows no sign of fluid being mixed in. i had him ride it again for a short little bid and it continues to blow smoke especially when reved up. also notice fluid coming out, not alot but little splatters when reving the bike. looks like water to me not thick enough to be oil. doesn't have much odor to the smoke at all. Any help or ideas will be helpful. thanks in advance.

"Blow by". Combustion gasses escaping past the piston into the crankcase, and then out the breather. Entirely normal to an extent, but could be excessive, too. Does the bike use oil?

Does not use excessive oil at all, oil changes are done about every 3 rides so not sure we would pick up on that very easily. could some bad oil maybe be possible? we rode yesterday hard for about 4 hours and it didn't smoke at all. or maybe something else. thanks

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