Clutch plates stick from sitting

If my 650 sits for several days the clutch plates stick. Pulling in the lever does nothing. Rocking in gear will finally break them free, but it's not easy. Causes,thoughts?

When they are free, shifting etc is ok on short rides. I don't ride enough on it to get issues from heating up.

racerdave,

When you park your bike, secure the clutch lever with a tie wrap to keep the clutch plates separated.

Good idea Pete, but not being a smartass that kinda a bandaid. Maybe a necessary evil?

What is the cause?

racerdave,

You could try using a different brand of oil. I am currently using Valvoline Motorcycle oil. I used ordinary Pennzoil for years until they changed the formula. But, in your case, any oil except the one you are using now. When you change it, use the clutch tie wrap trick and let it drain overnight.

maybe put some seafoam in the oil to un-gunk your plates?

I agree with changing the oil. Some oils are not as thermally stable as others, and they will get very tacky when they cool down. Motorcycle specific oils and diesel oils tend to have higher thermal stability. With an air-cooled bike, it is pretty important to keep your oil fresh, and changed regularly. I use Shell Rotella T 15W40 in my Road Star, and the plates do well. A touch of stick is hardly ever totally avoidable. My SV650 is running 10W40 Mobil 1 synthetic, and it still does it, although very lightly, if I don't run the bike at least a couple of times a week.

My 63' BSA is worse than the Yamaha.