Oil in air box on top of carbs

Guess I should have taken some pics, but I'll try to describe what I saw.

I had the gas tank off... replacing the handlebars and cables. There is an air box on each side on top of the carbs with a piece between the two with some foam between the pieces. The left side foam was oily with more oil toward the rear carb. I also noticed more oily dirt on the rear of the left box. I took the left side off to look inside. Both front and rear carbs looked the same. The rear might have had a little oily feel but if it did, it was not much. The box was more oily to the rear. I didn't see any oil up front, coming from the filter boxes. I keep my oil level about half-way up the site glass.

My gas mileage has never been very good and has been worse the last few months.

There are three vent tubes underneath on the left near where the center stand is mounted. Two are pretty heavy with oily dirt. One was venting a lot of gas fumes and an occasional drop of gas.

Any guesses? I sure don't won't to put it in the shop.

Don't know but I get oil around the carbs and necks also. Always has. I have just taken to cleaning them once a year. You run any Seafoam thru it lately ?

Oil in the air boxes is normally a sign that the crankcase was over filled at one time or another. These motors are not very tolerant of overfilling the oil. Make sure the oil is not above the middle of the window.

Since the RSV has a really bad lean angle when on the sidestand the oil tends to pool up in those airboxes, especially on the left side. Im guessing that the oil gets pulled up there while the bike is running while on the side stand. One cure is to only add 3.5 qts when changing the oil, not the 3.9 recommended. While it wont eliminate the problem altogether, it will reduce it. I just had my boxes off for cleaning. I had less of a mess than when I did it several years ago. My foam between the vent was also deteriorated so I gut out some gaskets from thick material and replaced it.

Buddy... I run Seafoam several times a year. I don't remember when the last time was which means its probably time to do it again.

Steve... When I first got the bike, I filled with oil almost to the top of the sight glass. Learned here that was the wrong thing to do. I haven't filled it past half way in the glass in the last 25k (or more) miles.

Jeff... I've never really measured how much oil I put in. I fill it half way up the glass, run it a bit to fill the filter, let the oil settle back for a bit, then bring the level back up to half way in the glass. I never really considered the lean angle and running the engine while on the side stand. I have the leveling links which increases the lean angle even more. While we have had a fairly mild winter, there have been some 30 and 40 degree mornings where I would start and run on the choke... usually longer than necessary. Could be that even though I'm only half way up the glass, the extra lean angle with high rpm warm up might be pulling a little oil.

Thanks all.

Had the same problem. When I bought the bike, I went through it, changed all the oils, plugs, etc. When I changed the air filters, noticed oil in the box on the left side and up in the airbox on top, again mainly left side. When I looked at the sight glass, noticed it was up to the top, I kinda figured that might be the problem (at least thats what I was hoping).