About 2 weeks ago I was changing my spark plug in my 2000 DRZ400s. Anyways, my friend was talking to me the whole time and about the time I tighten the plug in all the way he tells me something is leaking. I touch it and it smells like oil, so I follow it and notice it is coming from where the shift lever connects to the case. I put a pan underneath it and let it leak. I am pretty sure it dripped every last drop of oil that was in my bike. So my question is what could the problem be and how do I fix it? I looked up a parts diagram and there is an oil seal inside where the leak is coming from, but I'm not sure if it would be as simple as replacing that(if that is even simple) Any suggestions would be helpful. Thanks guys.