HI,
I've got a intermittent problem which has been plaguing my mind for a while, and after various searches, investigations, readings on this board, I have yet to come to a conclusion which satisfies .... so:....
Here's the story.
I have a '01 bandit 600. 40,000 miles on it.
Everything is stock (as far as fuel, oil, exhaust is concerned).
About 2 months ago, I added some oil, and I think I overfilled the level.
Started noticing some sluggish running on some days. The engine felt like it was running much hotter than usual.
The problem would go away sometimes after letting the bike sit. I had even done a couple long runs with the bike and no problems. However, sometimes it would take only 10 mins to get sluggish.
I decided to drain some oil, and ended up losing it all, so replaced with non-motorcycle specific oil.
Rode the bike like this for another 3 weeks, and I am still riding now. The problem has persisted, for the most part.
NOW,
I've pulled the plugs, and the 2/3 plugs are wet. They are wet on the threads and near the spark gap, and as well, it seems like there is some wetness on the ceramic and a bit in the chamber where the wire goes.
I say wet, and not wet with oil or fuel, because i'm not sure. I suspect it is oil though, from its color, viscosity, etc.
Also, there has been oil in the airbox. From reading earlier posts, i expect it came from the breather overflowing. This oil in the airbox happens after the sluggish riding.
So, I have a few conjectures:
1. Overfilling the oil increased pressure in the crankcase, letting oil past the piston rings to the combustion chamber. This caused wet plugs, and also increased pressure led to oil in the airbox.
- problem with this is, wouldn't the issue be solved once I have rectified the oil overfill. But, now that the oil is at a proper level, plugs still seem wet.
2. Blew some seals/o-rings when the pressure was high in the crankcase. This leads to the constant problem of oil in the airbox or oil leaking into the spark plug holes.
- Specifically, i'm directing attention at the gaskets which seal the spark plug holes between the valve cover and cylinder head. There seems to be oil leaking from the cylinder head gasket in front, but I have read that there is an oil overflow drain from the spark plug holes to the front of the engine at the cylinder head, which could be mistaken for a cylinder head gasket leak.
3. Engine is old, piston rings are questionable, and overfilling the oil exacerbated the problem. Oil is now running past the piston rings into the combustion chamber.
- Don't want to believe this, but seems more likely.
4. Oil i'm using now is the wrong grade, or improper, and by changing it I'll be alright
- Direct rationalization for not believing no.3
Lastly, I had recently cleaned the air filter. It hadn't been cleaned in a long time, and seems to have given the engine back some power.
I hope some light can be shed on this problem. I'm planning on a long road trip within the week, and I'm becoming nervous about the piston ring leaking.
I would appreciate an estimation of my problems and reasonable solutions. And suggestions of weather a long road trip is advisable given the different possibilities.
Thank you..!!!!