THE BICKERTON PORTABLE BIKE REALLY FOLDS UP WHEN THE GOING GETS TOUGH

Would you believe an absolutely theft-proof bicycle? Up to now, the so-called portable or folding bike has been neither as transportable nor as collapsible as its name implies: it weighs too much (usually about 40 pounds), takes some tussling to fit into the trunk of a car (fixed handlebars can get in the way), usually requires a wrench to put it together and needs separate accommodations on a train or plane.

Enter the Bickerton Portable bicycle from England, where, at the 1976 Business Efficiency Exhibition, it was listed among the 20 best British inventions in the last 20 years. The Bickerton comes in single-or three-speed, the latter weighing 25 pounds. The bicycle can be assembled or disassembled in less than a minute without tools (the unofficial record is 30 seconds) and, when folded, fits into a canvas tote bag that otherwise hangs from the handlebars. The folded bike is so compact (30" by 20" by 10") that, packed in its canvas bag, it can be suspended from a hat rack, stored on a shelf or checked in a restaurant cloakroom. It also meets U.S. safety standards.

Made mostly of aluminum alloy (no paint to chip), the Bickerton is virtually rust-free. The handlebars and mattress-type seat can be quickly adjusted to accommodate any rider, child or adult. Wheels are equipped with Michelin white tires; the 57-tooth chain wheel requires only the scantiest lubrication, and the racing-type transmission makes the Bickerton easier to ride than a conventional bicycle. The biker puts it all together with fixed "quick action clamps."

The portable was the brainchild of Harry Bickerton, an aeroengineer who, before he got into hand-carried bicycles, was in charge of design and development for de Havilland Aircraft, which built the Spitfire.

Now for the bad news. The three-speed costs $395; the single-speed, which weighs only 22 pounds, $350. But before you do a double take, ask yourself how much you paid for your current bike, and how much it would cost you to replace it if you went to the bike rack and found only an empty space.

The Bickerton Portable is obviously ideal for harried urbanites. The empty tote bag can carry an executive's briefcase, a student's textbooks or 20 pounds of groceries. For dealers in your area, query Handleman's, 16 Reservoir Rd., White Plains, N.Y. 10603. You may soon join those chaps in England who call themselves Bickertonians.