TOPIC:

I went through the process of changing my chain and sprockets. Once everything was back together I discovered a heavy oil leak at the seal where the clutch pushrod slides in. I've ordered a new seal but it seems strange that I should have such a heavy leak when there was no leaking prior. Any thoughts??

ya probably cleaned off the old layer of goo that was sealing it!

or you pushed in some debris that you loosened up, the pushrod drug it into the seal. pull the rod out and clean it. then clean out the hole and try again.

Those clutch push rods are notorious for building up a layer of grime/dried oil/chain lube/etc on them and eventually causing the seal to leak.
When you go to replace the seal remove the push rod, clean the grime/etc off of it, then flip it 180* and reinstall it. That way the area that once had the grime/etc on it is now inside the engine and won't damage the seal again.