here in Utah, the dealers Must re jet all new hondas out of the crate,
I live at 4800 ft and last weekend i rode trails up right 10K, elev.
your Honda dealer should have a high altitude jet kit, that consists of a # 155 jet for the Rocky Mountains,
They usually come stock from Honda with a ( sea level) jet that is a # 158 or close.
New Honda jet # 155 will run about $10 to $12 around here.
good luck..........