I see this is a GS500 thing. I have searched and read that some of you have replaced the two little seals where the tach cable connects to the cylinder head to fix the leak. $10 in parts it looks like to me. The question is; is it hard to get the cable out?
I was able to unscrew mine and tried teflon tape which worked for a while but the cable itself resisted coming all the way out. I really don't want to break it trying to fix it ya know. So does it just unscrew then pull out or what?
Last time I did it was a while ago, but if I remember correctly you just unscrew it (should be able to do it with just your fingers) and pull out. I had a leak, and changed the two seals, but it turned out not to be necessary as my old seals were in good conditions. What helped is pulling out the tach cable and any oil lingering there. Initially I put too much oil in the crank case, and getting rid of the excess solved the tack cable leak for me.
Good luck
I think we are good on the oil level but I appreciate all ideas and comments!
You know it could be that the design of the engine favors excessive oil in that area.
I replaced one seal today and put a little high temp gasket seal on the threads just because.
We'll post back after riding it a few times.