Engine blow by

How much blow by is normal on these bikes? When it's running I can feel the air moving at the vent tube. After a ride it drips some oil out of the tube.

Is that normal?

Completely normal. Do a search, it's been covered many times.

Thanks for the answer. I tried the search but came up empty- probably not using good search terms.

Most of my engine experience is with cars and my street bike that are multi-cyl and have crankcase recovery vents. This open venting is a little new to me.

It can be a little messy if you have a skid plate. Some guys run them back so it drips on the chain while others run them to their airbox because if you stall during a water crossing it can suck water up while kicking it. One guy ran it up in front of the gas tank and put a breather on it.

Mine does exactly the same...when I bought it, previous owner had run it up over the airbox...oil everywhere! I ran it down to the skidplate, finally rerouted so it aims at my chain, might as well make use of the drips. Just noticed today how much air shoots out of there, too!

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