actually cold air and hot gas is what you want, higher gasoline temps promote better atomization of the fuel. most mopeds wont be helped by a 'cold air intake' because they are already getting pretty cold air. these improvements are usually only good for 3 hp on a 200 hp car or truck, they wont be noticeable on a 2 hp engine.
high altitude, jet leaner- less air means you need less fuel. do a chop and see whats going on.