Oily Residue Under the Gas Tank

[malenurse13]

I pulled the gas tank off yesterday to install the 2nd Gen RSV Ignition By-pass Relay from djh3.

First time I've had the tank off. What I noticed was a TON of oily residue on the left side, under the tank. Any idea where this is coming from and what I need to do to keep it clean??

 

[malenurse13]

Just so you know... I wiped off most of the oily residue before taking the picture. But you can still see how wet it is on the left side.

[videoarizona]

I went looking in the parts diagram and couldn't find out if that large hose in the middle that connects to the bridge between the two halves is the crankcase vent hose. If it is, then I would say the oil is coming from the crankcase from being slightly to full and running down the freeway at high speed. Or the vent system is blocked some how. The reason for more on the left than right is probably due to the bike being on the side stand and the oil from the hose is moving with gravity to the left.

Edited June 30, 2018 by videoarizona
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[Great adVENTURE]

Some will say too much oil when an oil change was performed. I have wiped clean and have been meticulous on my oil fill level and still seems to collect there and on the left side carborators. I’ve checked all boot connections and hose connections and all are snug. Good to know I’m not the only one who suffers this left side residue. Someone will chime in with the answer for sure.

[steamer]

This has been covered several times in the past and everyone seems to agree that it is from oil level being to high. the general concenses is to fill the oil to half way between the high and low marks. The kick stand theory is also on the top of the list as to why the oil collects at the left rear carb. However, my bike is a trike and the oil still collect at the left rear carb??? I don't think anyone has ever found a good answer as to why this happens.

[vzuden]

I keep my oil level about 1/4 up from the bottom of the sight glass with the bike level. Anymore than that and I have to pull all the plastic air inlet and clean the oil film. Same with my last bike (RSTD)

[malenurse13]

So if this means there's too much oil... Do I need to drain a little? Or can I assume any extra oil has already came out and leave it till the next oil change??

[bongobobny]

The answer to that is to look at your oil level at the site glass with the bike as level as possible when the bike has been sitting for several hours. Yes, quite possibly the excess has already been blown out already. The level wants to be just about halfway up the site glass...

[Sylvester]

I have the same issue ever since the bike was new in 02. Used to think it was the K&N filters that need cleaning and oiling but put that notion out of my mind. I keep my oil level at 1/2 site glass but still have the issue. Good point is that it won't rust!

 

[vzuden]

So if this means there's too much oil... Do I need to drain a little? Or can I assume any extra oil has already came out and leave it till the next oil change??

By its nature, a little oil goes a long ways and it spreads easily. It is hard to say, but I suspect you may be better off draining a little.