Paia is where the Hana Highway properly starts, even though the road has been climbing out of the Kahului plain for some time already. It is an old sugar and plantation town on Maui's north shore, a short row of weathered wooden storefronts, surf shops, and cafes with a very relaxed idea of the clock. Windsurfers and kitesurfers gather at the beaches nearby, and the trade winds that make them happy are the same ones that keep the air here cool and slightly salty.
Treat Paia as the last easy stop before the long haul. Haiku-Pauwela, a few kilometres on, and Makawao up the slope are bigger places, but this is where most riders settle their breakfast and their petrol. The road beyond is a slow business: it is often said to have well over six hundred bends and dozens of narrow bridges, many of them single lane, and the real total matters less than the rhythm. You are never going to get a run on it. Tour vans, rental cars, and drivers who have stopped dead for a waterfall will set the pace, and the sensible approach is to accept that and enjoy the jungle instead.
The town's history is the history of Hawaii's sugar era in miniature. Plantation workers came from Japan, Portugal, the Philippines, and China to cut cane for the mills, and you can still feel their mix in the old temples, the bakeries, and the faces on the street. The mill chimney is gone from the skyline, and the trade now is tourists and surfers, but the little wooden town keeps its plantation scale. It is a fine place to learn how a very international island came to be.
Come early. By nine the street fills and parking becomes a negotiation, and a rider who wants Hana before the afternoon showers should be rolling by eight. Ride it on a weekday if you can. Showers can arrive from the mountain at any hour, so a rain layer on the bike is no weakness. Bring cash for the roadside stalls farther along, and top up the tank here or just down the hill, because stations get scarce once you are into the rainforest.