Not really biking (although you can bike there), but Chiang Mai has alot of offers when it comes to trekking, Atv's rafting and such. I volunteered one week at Elephant Nature Foundation,www.elephantnaturefoundation.org, an non-profit organization rescuing Thailands elephants from the torture of street-begging and tourist-rides. Here they come to live a life in peace, just being elephants. During the day they are fed and washed in the river, but they just trod along and do as they like. So you will most likely see some ellie-action during a day here, be it fighting or proper action. The park takes day-visitors, overnighters and volunteers, and most of us stayed way beyond the planned time. It is not the cheapest of tours, but thinking of what the money goes towards and the experience you'll get, it is worth more! When I arrived, there was a new baby in the park, only 4 days old. She was badly hurt when she was born, because their owners where drinking and didn't check on the mother until morning, when the baby had suffered a severe beating by rolling down a hill and not getting oxygen (her mother was chained, and could not open the bag they are born in). We saw her go through some amazing progress, from not being able to stay up to roaming about not wanting to lay down. She even started playfighting us (quite an experience playfighting a baby, weighing more than 100 kg..) If you want to ride there yourself please contact the office on Moon Muang RD, just south of Ta Pae Gate, first. The ride is and easy 70 kms north of Chiang Mai, most of it on sealed road, last part on half gravel half concrete slabs). But opting for the brand new minivan they bring most people in, you will get a briefing on the situation on Thai/asian elephants (not good, even though they are important in Thai history and mythology, there are no legislation protecting them, and they are subject to quite some terrible torture. And they are endangered as all hell), and you'll see a Natural Geographic documentary on it, so kicking back in the van is a good option. And.. please don't support elephant begging in the streets.. they are not supposed to be in a city, or to carry tourists on their backs.. I'm horrified to find such enormous creatures being left helpless after humankind has tortured them into madness, but seeing the lives they live at the park gives comfort.