Oil Dripping (THICK) from muffler exhaust connection

[Shredstar]

Hi guys just bought a KX250 2004 model, when i run it, it all seems fine and runs ok, i dont race i just ride for fun in fields/occasional jumps etc, but theres a problem with thick black oil leaking from the rubber connection where the muffler connects onto the exhaust pipe its dripping onto the swing arm and making a right mess, im not too bothered what it looks like, just bothered why its so rich and thick surely this is not normal, im just worrieds that if i removed the poor excuse for the rubber muffler to exhaust connection and put some 'propper' rubber connection on the thick oil will remain in the exhaust and eventually run back to the engine which cant be good thats why ive let it carry on dripping out (like an oil feature )
anyone got any ideas please? please bare in mind im very little mechanical minded.

[iamsofaking]

I have the same issue and I have been told that it is a jetting issue.  The bike starts right away and runs great, so I just wipe it and live with it.

[Shredstar]

Ye that's what I was thinking, but there's a lot of work (for someone like me) jetting my bike ha! U wouldn't have a clue where to start but I guess ill have to if I want to sort it out!

[sandblaster]

It could be jetting, it could be in need of a top end, it might even have a spooged up muffler, dirty air filter, or a combination of any of the 4.
The easiest thing to do is to pull off your carb and verify the jetting you have.
Then tell us what altitude you ride, what oil to gas ratio you run, and what type of oil you are mixing.
With that info we can start making some good suggestions on where to start.

[Shredstar]

Was worried about the top end.. I've heard that crop up on other posts, I've just cleaned my air filter it was like a Christmas pudding, jay waiting for it to dry out before I apply notoil spray, I run at 40:1, is it an easy task to remove the carb and what am I looking for when I do? I can supply pictures as I do this to aid this process
Thanks for your help by the way!

[Shredstar]

Just realized I only answered half them questions! Ill answer the rest once I get home and find them out

[sandblaster]

Christmas Pudding?
Was the filter black with oil or just dirty with dust and mud?
Removing the carb and pulling the jets is easy.
If you don't have a Clymer service manual I highly recommend that you get one.
It will save you a lot of time and some serious coin.

[KevinTwoStk]

I would also remove the spark plug so you can inspect it. That's one of the best ways to determine whether or not your jetting is in the ball park. Most manuals have a series of sample photos that you can compare your spark plug to.

No matter what the jetting, it seems that all two-strokes eventually fill the silencer packing with oily sludge, and any loose exhaust connection is prone to dripping.

[Shredstar]

Sorry for such a late reply!! Just had a graft on my ear drum..
Yeah when I said like a Christmas pudding I just meant dirty light brown but it's nice and clean now, and reapplied all the no toil air filter cleaner stuff,

I'm just about to strip the muffler and check the wadding for saturation and if needed re pack i take it this is necessary?

Then Ill start stripping the carb down bare in mind I'm a complete amateur at this so ill have my little gopro cam at the side so I know how to put it back together any advice would be great and what to look for

Does this all sound ok?

[sandblaster]

Take a look at how to jet your KX500 here:
http://www.oem-cycle.com/forum/viewtopic.php?f=5&t=109&hilit=SAFELY+JETTING
There are some pics there that will give you a good idea of what you are going to be seeing.

[Pmcg]

That's a great link!  Thanks.

[Shredstar]

That's a brilliant read! I've gained so much knowledge from this and will certainly give it another read tomorrow, would i be advised to purchase some sort of jetting kit? Is this necessary? I'm planning on stripping the carb tomorrow.

I stripped the rear exhaust (muffler) and the packing seemed oils but not saturated  but I think due to the oil mainly not goin up there more going onto my swing arm instead?

[sandblaster]

Jet kits aren't really necessary.
Just pull the main jet and the pilot jet and tell us what the numbers are.
Also, verify the needle number and the clip position.
Pull your plug and take a pic so we can see what it looks like as well.

[Charlie500]

How does the bike run at wide open throttle? does it blow out tons of smoke, spit and sputter a little bit? your main jet may be too big... Does it idle? Does it rev up clean and crisp off idle? that could be your pilot jet... Make sure your needle is in the second from the top clip then dial in your pilot. you can fine toon it with the needle clip up would lean it, down will richen it. The Main jet is pretty much for just wide open throttle.... I ride at 1000-5000 feet elevation and had to put in a leaner pilot and main jet. I also put in a leaner needle.... you can look up a thread on my carb tuning....Its pretty recent.

http://www.kxriders.com/forums/index.php/topic,11498.0.html

Correct me if i'm wrong guys...

[Shredstar]

Hi guys I've stripped the carb easier than I thought it would be!! Hopefully just as easy to go back in ha?!

These position you speak of

The main jet came out with the spring connected with the throttle cable I've disconnected the spring and the throttle cable so there's the needle still sat with what looks like an old flip lighter so I need to remove this if so how without damaging it?

If taken a few pics see if you guys make any sense of what I've done or where I go from here now f the carb apart please so far so good