In China, outside the densely populated areas, the motorcycle is king.
Bus and van travel do not match the freedom of having your own two wheels. Outside the city, the ubiquitous red, 150cc Jialing motorcycles are the primary form of transportation. Although 150ccs may not seem like much, these sturdy bikes provide just enough brawn to crawl up the highest 5,200-meter-plus passes in Tibet and Qinghai. I have ridden a 150cc Jialing motorcycle from the Chengdu basin to Mt. Everest Base camp, then north through Qinghai and into the Gobi desert, and finally south all the way to the Burmese border at Ruili in Yunnan. These little one-cylinder beasts cost almost nothing to maintain and fuel, but can take grueling punishment on some of the harshest roads in the world.
If you are going to buy a bike in Chengdu, make sure to buy a Chinese brand bike or a small 125cc Yamaha or Honda designed for the Chinese market. The larger crotch-rocket bikes and even the 250cc Honda dirt bikes are smuggled into the mainland from Hong Kong and often arrive in Chengdu thoroughly thrashed. You will lose a lot of money if you buy one of these bikes: Spare parts and capable mechanics for these smuggled bikes are both rare and expensive. One the other hand, spare parts for domestic bikes are readily available in both cities and remote areas, and just about every town in China will have an experienced mechanic who can also fix flat tires and weld. The best bikes today for long-distance travel are the 200cc Kinlon dirt bikes, 150cc Jialing dirt and road bikes, and the 125cc Yamaha YBR with a front disc brake. None of these costs more than 6,500 RMB new and can be found along the Third Ring Road near the 川藏立交桥 (Chuanzang Flyover). Dozens of shops along the Second Ring Road sell used bikes.
Once you've got your wheels, you'll also need a license and some tools. The driver's-license test is a 100-question computerized test that anyone with a foreign license can take in Pixian (郫县) for about 250RMB. A massive tool and spare parts wholesale center is located on the north side of Chengdu. Take the Third Ring Road and exit heading north at the 成彭立交桥 (Chengpeng flyover), then cross one bridge and turn right into the parking lot immediately after the bridge by a large Yamaha sign on the side of a building. The main tools needed for travel are Phillips and flathead screwdrivers, wrenches for loosening the rear wheel and adjusting the chain (usually 19, 21, 12 and 14mm), a spark-plug socket and spare plug, and an Allen-wrench set. Before hitting the road it is a good idea to buy a custom rear rack or at least reinforce the welds on an existing rack. Rack breakage was the worst problem I encountered traveling in China, but there are excellent welders in Chengdu who build quality racks for less than 20 RMB.
Finally, enjoy your travels and keep a few things in mind on the road. Check the chain and oil daily. New parts are very cheap; oil changes at most 25 RMB, and clutches, starter solenoids, chains, and air filters are rarely more than 15 kuai installed. A good set of ChengShin tires are worth the money. Most importantly, don't ride too fast. Take it easy, enjoy the views, and happy riding.