Although the tropical climate makes it hot for biking, the Puerto Vallarta area is lovely and has challenging and varied terrain. Aim for the relatively cooler months of November through mid-April. A few operators lead rides up river valleys to Yelapa and from the old mining town of San Sebastian (reached via plane; included in price), high in the Sierra, back to Vallarta. It's about 45 km (28 mi) of twisty downhill.
In the rainy season, showers are mainly in the late afternoon and evening, so bike tours can take place year-round. In summer and fall rivers and waterfalls are voluptuous and breathtaking. A popular ending point for rides into the foothills, they offer a place to rest, rinse off (there's lots of mud), and have a snack or meal. In dry season, it's relatively cooler and less humid. The very best months for biking are December through February: the weather is coolest, and the vegetation, rivers, and waterfalls are still reasonably lush after the end of the rainy season in October.
Four- to five-hour rides average $35 to $45; Yelapa costs $110 and up. The ride down from San Sebastián, including one-way plane trip, goes for around $150. Rides of more than a half day include lunch, and all include helmet, gloves, and bikes.
Eco Ride. A few streets behind Vallarta's cathedral, Eco Ride caters to intermediate and expert cyclists. Most rides start at the shop and go up the Río Cuale, passing some hamlets along single tracks and dirt roads. A few rides include time at local swimming holes; the Yelapa ride ($115) starts in El Tuito, about an hour south of PV (you get there by vehicle), and enjoys some magnificent scenery—with two 10-km (6-mi) uphills and a 20-km (12-mi) downhill—returns by boat after lunch on the beach. If cycling is not your thing, no worries: they now also offer hiking tours. Calle Miramar 382, Centro, Puerto Vallarta, Jalisco, 48300. 322/222–7912. www.ecoridemex.com.