Like many here, around 34,000 miles on my baby, I developed the small and annoying weep hole oil leak. Many have reported this happening as early as a few thousand miles, and some never seeing this happen.
Summary of problem is, there are two seals for the cooling system/water pump, and the lubrication system/oil pump. They both share the same shaft, therefore they each have their own seal to separate the coolant from the oil and vice versa. Depending on which seal is failing, you may either see oil and/or coolant come out of that hole.
In my case it was only oil, and this never got bad enough to drip on my driveway, but it was enough to run down my engine case and make it look nasty (probably a drop or two per ride). Totaled up over the week, it annoyed me enough to try something.
Easiest solution if any of those seals is bad AND REQUIRES REPLACEMENT is to simply replace the whole right-hand engine side cover, which comes with new bearings and seals pre-installed. BUT BEFORE DOING THAT, try this first.
I am NOT normally a fan of engine additives or stop leak products; I find they're all hogwash or simply swell the seals. But this actually softens seals that are simply hardened over the years, and are otherwise in good shape (e.g.: not cracked, torn, ripped, or worn out). This does not puff them or swell them up, which many products do, resulting in eventual failure again. Also, it can be added to transmissions, so it's safe for clutch materials.
One bottle treats 6 quarts, so with 1.4 quarts or thereabouts in our crankcases, I added a shot glass full (without vodka) which is around 1.5 ounces (bottle is 8 ounces) before work, and drove as usual. One-way work is about 30 minutes, so each day is about an hour of riding. This product advertises it may take 5 hours to work, but obviously with our smaller engines, it started working much faster for me. After the first day, the drop hanging on the nipple was down to just a smidge. I cleaned it with brake cleaner and wiped dry, and after two days, no dripping whatsoever.
I'm a believer in this product, as long as those specific conditions are met - 1. Your seals aren't damaged and the leak is minor, 2. Add the proper amount to healthy oil, and 3. The shaft hasn't got a grove worn in it.
Worth a shot, and for $11 on ebay, well worth it for me.