Leaks from the muffler

[Soundplot]

I have search though a lot of the postings here and haven't found what I was looking for. I do admit that I am new to motorized bikes and so I might not be searching the key words needed to produce the results I was looking for but I do have a question. I have come to learn very quickly that these bikes do tend to require a regular amount of maintenance. I am OK with this fact and still greatly enjoy owning the bike, heck, I would get a second part time job just delivering pizza with the bike if I thought it would be reliable enough for that kind of mileage. I have had the bike for about two months and have already put more effort into fixing it then I have my last two cars (currently its in the shop to get new and better bearings put into the back tire.) But I have noticed something new. The engine has started to leak what looks like oil from the muffler after the engine has been running. Its not a large leak just a small puddle of like 10 drips. I fear that this is a sign of a problem I have yet to come into contact with yet. I'm sure it is more the likely caused by a bad seal of some sort or another and I plan on looking into that when I get the bike back, its about time to clean out the carb anyway. But I post it here because I am wondering if it was something that I did to promote or help this problem come along.

Leading up to the leaking I noticed that the bike was getting a bit slugish, nothing too bad but it was getting harder to cold start and it didn't seem to have as much zip. I did some research and ended up cleaning out my filters in the gas tank as well as inline. I also upped my oil ratio but not by much, (a splash or two over 20:1) I was told by a small engine mechanic that running it a little richer every once and a while can punch out build up and help with the motor overall. I put the bike back together and rode it around for a while, it seemed to be doing fine again but when I parked it, it was the first time it leaked. Are these two thing related? I fear I have just wait and see what happens I will have a larger problem on my hand. Any suggestions would be great! Thanks

Talk Hard

 

[Dave C]

These things are hi-matinence like an up-town blond The more reliable motors are the Japanese 4 stroke motors. Smoother running, better put together, longer lasting, just generally better all around.

It's really hard to say what's up with your 2 stroke. With the oil-rich fuel these things burn I'm not suprized there's drips from the exaust from unburnt oil. While it is a good idea to run like the first gallon rich when it's broken in I'm thinking of a ratio of 32:1 with the oil I'm using, XPS. A real clean burning synthetic oil ment for watercraft like jet skis. Because of enviromental concerns that type of oil burns more completely than most to lower polution in the water.

I've kinda wondered about the oil collecting thing on my bike because I have an expansion chamber.and I can't help but think there's a pint of unburnt oil in the bottom of it....but I hope not

 

[motorpsycho]

oil dripping out of the muffler is common on 2 strokes, especially if you are running it at 20:1.
think about it, you are putting gas and oil into the cylinder, some oil is bound to not get burned and it collects in the muffler. after awhile, it will drip some of this unburned oil out of the muffler.
Look at your 2 stroke weedeater muffler (if you have one) and i guarantee that you will see oil residue built up in and on the outside of the muffler. the way a weedeater muffler is, there's nowhere for a large amount of oil to collect to make it drip out like on the bike muffler.
Inside the stock bike engine muffler, there is a catylist cylinder that consists of a steel tube, with corrugated "steel" coiled up inside of it. This is a huge trap for oil, and it will build up over time and drip. Every 2 stroke will drip oil out of the exhaust or it will spray a very fine mist of oil out of the exhaust if the pipe and muffler are not very restrictive.
I'm running my 2 stroke bike engines at 32:1 and i still get a drip every now & then. I'm running a non restrictive expansion chamber and a modified baffle on one, and a straight pipe with a modified baffle on the other.
My exhausts are not as restrictive as the stock exhaust, and i still get drips of oil coming out of them on occasion.

your oil drip isn't like a bad seal because there's no oil contained in the crankcase (like a 4 stroke). the oil that lubricates the bearings is the oil that you are putting into your gas. This gas/oil mixture actually goes into the crank case to lubricate the bearings before it goes into the cylinder to be burned.