His pounds 21m has come from cashing in his chips - a 10 per cent stake in the company - so he has had time to get used to being wealthy. But he also seems genuinely uninterested in wealth. His one luxury is a Ferrari 456; he has one house, no helicopter ("I hate flying"), no yacht, no flash. An Essex man, he is in danger of undermining that species' reputation.
Something else surprised me about Lloyd. He played in the final of the Davis Cup once, a rare feat for a Briton, and spent many years on the international circuit. Yet he is small - 5ft 8 at the most - and pigeon- toed. How on earth did he do so well in a sport where power and physique are vital?
The answer is simple, and explains a remarkable twin career. I had assumed he was a brilliant tennis player who used his name to launch a chain of glittering clubs. In fact he was a good tennis player whose dogged determination turned him into an excellent one; then he was an unknown businessman whose dogged determination turned him into a highly successful one. "I have to win at everything - even tiddlywinks," he says.
Lloyd is a youthful 47: floppy-haired, sun-tanned face, Essex accent - a combination most television producers would die for. If he did not have better things to do, he would undoubtedly spend much of his time chatting on the box. That's another career for him - he will never be out of work, David Lloyd.
He was brought up in Westcliff-on-Sea, near Southend. His younger brother John also became a tennis pro and for years was the Great White Hope of British tennis. Their father had a clothing business, and was a sports nut. When David passed his 11-plus he was given a racket-stringing machine, which helped his tennis but also launched his business career. "I made quite a lot of money stringing for the club," he says.
At 14 he was one of the best schoolboy players in the country and the following year, with two O-levels and his parents' blessing, he set off on the tennis circuit. It was tough. He had to hitchhike to tournaments, and used every scheme he could to make a few bob. When he went to Germany he took gut, and sold it at a profit. En route to a circuit in South Africa he took a suitcase full of the dresses his father made, and sold them to department stores across Africa. "I became an entrepreneur by necessity," he says. He had picked up basic book-keeping skills from his father and was handy at sums; by the time he was 20, he was a seasoned businessman.
Sport and business jogged side by side. He won Junior Wimbledon in 1966 and put his winnings into the stock market. When he was 24 he married Veronica, another player, and switched the money into a house. But he continued to stock up his piggy-bank. He never had a manager, and became skilled at getting the best deals on hotels or flights. He also had a sideline - he was (and still is) a passionate card- player.
When he was 27 he decided he was bored with living out of a suitcase. He would spend only half the year on the circuit, and work for the rest of it. He found himself a job at a tennis club in Canada, which was a revelation. Unlike British clubs, it had no strict rules or alarming league tables; instead it encouraged members to do what they wanted - play, drink coffee, swim, whatever. Members would pay a subscription, and pay extra only for food and drink. Lloyd decided this was his future. "I thought I've just got to do this," he says. "From then on I saved every penny to go for my dream."
For four years he visited as many clubs as he could, seeing what he liked and what he didn't, and developing his idea of the perfect tennis club. In 1980, when he was 32, he had an architect draw up plans and started to look for suitable land. He knew where it would have to be: close to the junction of the M4 and the planned M25. The sort of people he would attract, he believed, would all have cars.
Hounslow council wanted a leisure centre and had spare land on the old Heston Aerodrome, by Heathrow. It was a dream location - 2.7 million people within half an hour's drive. Then came the tricky part: raising the money. He could raise pounds 125,000 himself, but he needed pounds 1.4m. "I knocked on doors everywhere and almost gave up," he says. He faced two problems. First, he wanted to build something quite unknown in Britain; secondly, he was not an established businessman. "People kept saying you can't do it, you're just a bloody tennis player," he says. That just made him more determined.
Eventually he was contacted by Charles Haswell, the son of a successful structural engineer. Haswell said he wanted to invest and, having caught this little fish, Lloyd found ever bigger fish on the line. Eventually pounds 1.7m was assembled - Midland Montagu put up pounds 275,000, Haswell pounds 125,000 and Lloyd pounds 100,000. The rest, a pounds 1.2m loan, came from National Westminster Bank. Lloyd kept voting control.
The centre was an immediate success. "It was full before we opened," Lloyd says. He worked like a madman: cooking, cleaning, coaching, and sleeping there to save money on security. "You didn't know if you were making a profit," he says. He soon discovered there was one big difference from Canadian or American clubs: British people were less honest. "We lost pounds 7,000-worth of toilet rolls alone in the first few months," he says.
But the figures proved his point: in the first year, after interest, David Lloyd Leisure made a pounds 117,000 profit. He was still cautious, and, rather than financing the next centre from cash flow, he accepted a funding offer from a club member.
It was a disaster, because his partner had different ideas about how the centre should be run, and Lloyd pulled out three months after it had opened. That set him back two years, but in 1986 he was expanding again - and has continued to do so, even through the recession. "Our best summer was 1992, because people weren't going away on holiday," he says.
That was the year the company went public and Lloyd lost his name. "I had to sell when we floated but it was very hard to do," he says. "It's very odd being a brand name as well as a person." One of the reasons he is staying on as chairman now Whitbread has bought the company is to protect his name. "I want to make it bigger and protect it," he says. "I'm proud of it."
Whitbread understands this. It paid pounds 200m for a business with assets of pounds 40m. Most of the difference consisted of the value the brewer put on one man's name.
Meanwhile that man is doing something about another ambition: to improve the dire state of tennis in Britain. His clubs will help foster young talent, he hopes, and his new job as captain of the Davis Cup team will put him in a unique position to choose the most promising players. He believes he is the best person for the job because: "I've been outside tennis - I don't owe anyone any favours."
He could also (here's another career) write a best-selling book on management. His thesis would be simple: "If you have an inner belief, you will win." It is a message Britain's tennis players, businesspeople, cricketers - most of us, really - seem to have forgotten.