I own a 05 Kawasaki ninja 250r. I was riding down the highway one day when I noticed a burning smell. I stopped the bike to see what it was when I noticed some thing black dripping onto my exhaust right about where the exhaust begins from the motor. I took it to the shop and the mechanic said he thought it was oil leaking from my shift shaft because it might have a bad seek because it had been sitting for a long time. It has now been about 4 says since then and it has stopped leaking. Is it safe to ride and do I still need to take it in? I really don't want to spend another 120 to get it fixed when it's not even leaking now. Especially since I just spent 475 for a full bike tune up/repair since the bike had been sitting for about five years in a barn. The mechanic said the last repair did not cover this problem lol of course not. Please give me feed back soon!!!!
Last time I looked at ANY bike the shift shaft is not anywhere near the point the exhaust BEGINS from the engine.
If you are talking about the point at the front of the engine where the pipes exit the cylinder head, then you may have (or had) a leak in the valve cover gasket.
Another possibility: Oil was overfilled. If you overfill the Ninja, it WILL puke oil wherever it can and that can end up on the pipes, but usually at the rear section near the exhaust slip coupling. It COULD also push out at the valve cover gasket too.
Make sure you check your oil (Bike off, held completely straight upright, should be around 1/2 to 3/4 up on the sight glass....any more it's too full, any less and you lost a fair amount of oil and need to add more.)
Since you mentioned that it was recently serviced, it can also have been oil or greasy handprints from when it was serviced. (Another reason I always service my own bikes.)
I'd look into finding a new mechanic or better yet, get the service manual and learn how to work on the bike yourself.