Foam Can Get You Home?

By Dennis Santopietro

Q: Hi, I’m stumped. I’ve got a 2006 Harley-Davidson Fatboy with the fuel injection. I bought this bike new. I have Red Line synthetic oil in the engine. The oil level is correct. I ride an hour to work in the morning. I check the oil before I leave. By time I get to work, when I check the dip stick, it’s super foamy and is all the way up to the cap on the dip stick. When it cools, it looks normal and is back at the correct level. Any idea what’s going on here? It makes me worried I’m doing damage.
Thanks if you can help.
James

A:The “foam” is caused by air. The oil system is vented so this is normal. Air can not cause damage to your engine. Some bikes will foam more than others depending on the type of engine or engine oil. Some bikes will not foam at all. If your oil level is all the way up to the cap on your dip stick your m/c is overfull. The level should never be this high when your bike is hot or cold.

Related Video: Softail Oil Change

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3 Responses to “Foam Can Get You Home?”

  1. colin

    Signs of abad solenoid clicking sound

  2. Angelo Morales

    I have a 2006 vrod, I would like to change the rear tire for a fatter one, without any modifications, any suggestions?

  3. Rick

    The oil is drawn from the crankcase of the engine and stored in the oil tank. On Softails the tank is considerably higher the crankcase so as the motorcycle sits oil can seep from the tank back into the crankcase. When you check the level before riding it maybe low, you top it up and as soon as the engine is running it puts the oil back into the tank. Your oil level is too high. Another factor is that oil "grows" as it gets hotter. A practice that I have adopted is when I get home from a ride and while the bike is still hot, I pull the dipstick. This way the oil is still in the right spot and at the operating temp. As soon as I lock the ignition I check my oil. And I know the bike is ready to ride for the next time.