TIM Obendorf has a different way of experiencing China. He does it by the seat of his pants. What began as cheap entertainment and a way to keep fit during student days at Shenzhen University has evolved into a thriving business for the 30-year-old American. Where other cycling companies in Hong Kong and Asia have failed in maintaining cycling tours to China, Obendorf has a steady track record. ''The key to my success is size. We're small.'' His company consists of him, his wife, who runs the office in Tuen Mun, and a Chinese partner. ''We keep the group size small, usually six to 12 people, and take care of everything, like visas and bicycles.'' Since he founded International Cyclists to Asia in 1987, Obendorf has attracted locals, expats and foreign travellers who prefer to explore China's backroads from behind the handlebars of a mountain bike, not from a tour bus. The company offers 17 tours - ranging from a weekend foray into Southern Guangdong Province, an arduous 13-day trek/cycle adventure through the Tibetan highlands to seven days of gentle pedalling in and around the Sichuan basin. Tours are designed for a variety of fitness levels and cycling experience. The average distance for Hong Kong Chinese is 30 kilometres; for others, between 70 and 100-kilometres. His oldest client, 65, hadn't ridden a bike in 40 years. ''There's no pressure. If you're a triathlete and you want to race ahead, that's fine. Everyone goes at their own pace. ''Some prefer to cycle in the morning then ride (in the support vehicle) the rest of the day. Others just want to ride, stop and shoot pictures. ''You don't have to be an Olympic cyclist.'' Cyclists will eat simple Chinese food unless they bring their own snacks - candy, peanut butter, muesli, granola, cereal items. ''Breakfast is usually greasy dim sum.'' The day is organised with meal stops, meeting points and opportunities to explore villages. A support vehicle goes 10 to 15 kilometres ahead; an equipment lorry follows the group. Obendorf personally leads half of the tours; the others he entrusts to a fellow American who lives in Hong Kong and is bilingual. As a student in Shenzhen, the native of Portland, Oregon, would jump on his bicycle and pedal off alone for the weekend or a holiday. The idea caught on and soon other students joined him. His aspirations to become a commercial photographer were detoured when he answered a call for volunteers to work with Vietnamese refugees in Hong Kong. He came and before long was smitten with Asia, the Vietnamese people and Hong Kong. By the time his work in the camps was over, he decided to form a small business, organising cycling trips for the summer. It was on one of the early tours, with a group of Hong Kong Chinese, that he met his Chinese wife-to-be. They live in Yuen Long. What competition he faces comes from tour companies based in the United States who specialise in cycling. ''I'm different because I live here and the company is based here.'' ''China has not always welcomed cyclists. In 1986, they barred foreigners from entering China with bikes. That was bad news for cyclists because not everyone was aware of it.'' To mitigate the problem for himself, he started networking and found a young tour organiser in Guangzhou who enjoyed cycling and was interested in forming a business. Eventually, William Su, 32, became his partner. Su supplies the support vehicle and driver and the warehouse in China where the mountain bikes are stored. ''Many foreign cyclists who arrive in Hong Kong with their bikes and great plans to cycle China are shocked when they're turned away at the border or told to leave their new bikes behind,' said Tim. Not every cyclist wants to hook up with a tour. ''When you travel independently, you have great adventures. We're an option.'' Though the tours are designed for a variety of fitness levels, several are quite challenging. The 13-day Sichuan/Tibetan highland adventure is tough. ''The steepest inclines are made by bus, but in two days, we cycle from an altitude of 500 metres to 3,000 metres.'' Most of the expats are in pretty good shape and know how to ride. But the Hong Kong Chinese are ''horrible bikers'', says Tim. ''They're not used to cycling.'' For those groups, he holds training sessions before the trip. ''I teach about changing gears and balance. We have a good time.'' Prices include round-trip transportation, bikes, meals, lodging, insurance and visa. For more information contact International Cyclists to Asia, GPO Box 4262, Hong Kong. Tel 454-9191, fax 463-5520.