Guys, I was just out in the garage and happened to notice a oily trail on the right side of my rear cylinder chrome rocker cover. It appears to start up on top, but can't really tell because of the tank. It trails down and back along the cover. Not a lot, just a trail. Reason I noticed it is because I just cleaned the bike really good a couple of days ago and those covers were spotless. I wiped it off in order to see if it does it again. I also checked my oil and it's fine.

What could cause this and should I be concerned?

 

Gasket leaking most likely. Replaced rocker box gaskets on my evo a couple years ago. Haven't had to replace them on the twin cam yet.

 

The way it trailed down from the top, it looked like it was coming from the area of that one bolt that is up under the tank. Is it possible that bolt is loose and it's coming from there? It's the first time I've seen it, and like I said it wasn't very much at all.

Looks like I need to take it to the dealer.

 

When the gasket on my Evo started leaking it was on the rear left corner. It was a small seep but I got tired of having to wipe off the top of the transmission cover on the left side. It would put a film on it after a few days which was a dirt magnet. All my bolts were still snug but that paper thin gasket was brittle. I just figured the brittle gasket lost the ability to swell and shrink with heat.

 

That's what it was in my case. It only took about 1/8 turn to snug it up and solve the problem. Be sure to do it when the motor is hot, in case they were installed with red Loctite. Easy fix and nothing to lose by trying... other than a little time.

 

Thanks! I'll try that when I get home this evening. Will a box end wrench fit up in there? If not, I'll run it to the dealer as I do not want to pull the tank.

 

No need to pull the tank, at least on my street bob. You may need to unbolt and raise it up in the back, but not remove. A wrench probably wont work, but a socket may (depending on which bolt it is). But those fasteners have both a socket head and allen style head, so you can choose which will work the best (socket, socket with allen, or allen wrench). The bolt is recessed in the cover slightly if i remember correctly, thats why a wrench wont work.

 

Well crap. Thanks for the info. I thought maybe a box end, one with an angle to it, would work as the other two bolts that are exposed aren't recessed and a wrench will fit on those.

Thanks again for the info. I'll try that this evening.

 

Breather blow by?

 

I don't think so. Both the dealership and I make sure the oil isn't over filled. And there wasn't really enough to indicate that is where it came from. Plus, I think it would be in more areas of the engine.

This was just a tiny slug trail of oil coming down the side of the cover from the top, and trailing backward a bit. Looks like one good drop of oil and the trail it would leave as you're riding.

On a positive note, there wasn't anything on it when I got to work this morning. Maybe it takes a while to seep out. Either way, it'll be checked and fixed by tomorrow evening.