2008 C50T runaway idle when hot

[Dominiquer]

I just bought this bike from a dealership, after 2 year rides. Now that I've ridden about 100 miles on it, I notice two things;
1. When it got hot (stuck in traffic for 20 minutes) the idle rises to about 1800rpm (my best estimate). Is this normal for cooling purposes?
2. When I first start it cold, it sounds like piston slap, but goes away after it's warm. Is this also normal?
Thanks!