Go Back   Motorcycle Forum > Manufacturer Forums > Yamaha

Thread Tools
Old 08-26-2007, 10:24 AM   #1
John Chambers
Join Date: Aug 2007
Posts: 1
Default Oil in my air filter?

I have an '01 V-Star, is it normal to have oil in my air filter? It's not running to good, so I decided to replace the plugs and noticed this. I haven't noticed this before. And why would I have this issue? Please can someone help me with this. John
John Chambers is offline   Reply With Quote

Sponsored Links Remove Advertisements
Motorcycle Forum
Old 08-26-2007, 06:51 PM   #2
Founding Member
pplassm's Avatar
Join Date: Nov 2001
Posts: 3,875

This is a common problem with Harleys. Perhaps it's common on large capacity V-Twins.

Check the crankcase ventilation hoses/system.
pplassm is offline   Reply With Quote
Old 08-28-2007, 08:56 AM   #3
Founding Member
Join Date: Jun 2007
Posts: 540

A fair number of bike's will have crankcase ventillation hoses which connect to the air box. If the bike is overfilled with oil, or perhaps some other condition exists which is causing oil to be sent through the crankcase breather into the air box. If it's not a lot, I wouldn't worry too much, if it is a lot I'd check the oil level first.
bbtowns is offline   Reply With Quote
Old 12-01-2007, 03:59 AM   #4
Join Date: Dec 2007
Posts: 1

I know this is an older post but oil in the air filter on the 1100 VStars is the result of overfill. Excess oil is blown out through the air filter.
Redogs54 is offline   Reply With Quote
Old 01-14-2008, 11:55 PM   #5
Join Date: Jan 2008
Posts: 4

This is totally normal on these V-Twins. In fact Yamaha has run the crank vent hoses to little nozzles on top of the throttle bodies on the latest bikes like the Roadliner and the Raider. That way the oil mist from the breather gets sucked back into the engine.
Yes when you overfill, there will be more oil coming out of it, but even at normal levels you will always have some oil mist come out of it that over time builds up a layer of stinky gui oil.
fxstein is offline   Reply With Quote
Old 09-27-2009, 05:45 AM   #6
Registered Member
Join Date: Aug 2009
Location: Lake Helen, Fl.
Posts: 4

You say that the bike isn't running well and that there is oil in the air box. If it were me, I'd do a compression check on both cylinders. Reason being, if you were to have a bad compression ring, head gasket, or valve guide problem (does it tick, tick, tick?) the excessive blow by caused by that problem will manifest itself through the crankcase vent, which in your case is routed into the airbox, thus oil in the airbox. For your sake I hope that it is just overfilled with oil.
Good luck.

Bananas! is offline   Reply With Quote

Thread Tools

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off