So I just replaced the driveshaft seal on my 99 YZ400. Seemingly simple project - I remove the front sprocket and the seal cover (held on by the two bolts) and pop the old seal out with a hook. I oil up the new seal with motor oil and slide that baby in - put the cover back on and fire her up and see some pretty serious spooge coming from the area. I turn the bike off and remove the cover to realize that the seal possibly wasn't perfectly even all the way around so I use the square blunt end of a screwdriver socket adapter and tap it even so the new seal is evenly slighly countersunk all the way around - put the cover back on and fire it up, let it run for 10 minutes and as soon as I start hitting the gas a bit and putting the seal under any kind of pressure, I'm getting some pretty decent discharge from the new seal area.... Another thing, I bought a new o-ring like I was advised by my parts guy and couldn't figure out where to put it! It looked from every scematic I saw that the o-ring sat behind the bearing? I didn't see an o-ring when I removed the old seal either?? My roomate has been wrenching on cars for years and insists that the seal just needs time to seat and the leak will stop soon.....but I'm not sold! Any help would be greatly appreciated The worst part about it is the old seal was barly leaking! Thanks in advance.