I have owned two VStar 1100s, and have been stuck in traffic with them many times. These are strictly "free air" motors...no cooling mechanisms whatever, besides the fins.

Yet, these engines never got hot, at least not enough to be uncomfortable. Go figure.

The Chieftain I rented in Texas through some heat in traffic...not terrible, but definitely more noticeable than the Yammie...and this was in November.