If the leak is minimal I wouldn't worry about it. And by minimal I mean you don't see it on the ground but do see the residual around the seal.My bike just developed the same leak! So it's not oil? I love my bike, it's a 2014 and I bought it with 2,650 miles on it 18 months ago and to be honest I'm becoming more and more disappointed as I put more miles on it. It has 12k now and the engine is noisy and now I have this leak. Of Honda had metal fenders I'd be trading this bike in.
Pull the side cover(O2 one I think) and use a syringe or a small funnel with a hose and just fill it up IMO. Depending on the miles you always lose some. Like I said in the above older post, I was down like 1/4ish inch so no worries.I've a lot of blue residue around this drain ****, and has built up recently, i noticed while changing oil last week, and coolant level was below "low" on the resevoir,,, havent ridden since. I'm worried I'm gonna be making a visit to the yamaha dealer.
Update, took it in to have it looked at,,, about a month ago,,, was a worn gasket “between the transmission and another internal component”(Yamaha service dept words),, tear down of motor, covered under warranty. Still don’t have it back, yet.When you are riding hard and fast and it is hot out the fluid get really pressurized and may blow out a little. That is by design.
If you fill, then just monitor for a month or so. If it is stable then just wait till the full flush & fill is required.