I've experienced similar issues with my bike over the past week or so.
It's been over 100 degrees for the past week, and I feel the same "creeping".
Also, it's sometimes hard to get the bike into neutral.
This does not happen when it's cooler.
I'm running Castrol GTX 10-40 non-synthetic that has about 2000 miles on it.
I think I need to switch to a heavier oil...
Let's wait and see what other have experienced.