Spokes Men Peddle the Wares : Mountain bike innovations get a test run at the Interbike trade show at the Anaheim Convention Center.

If there was one defining image of this year’s Interbike trade show at the Anaheim Convention Center, it would be the sight of someone pushing down on the seat of a mountain bike.

The suspension revolution in mountain bikes is in full bloom, with about as many distinct approaches to the challenges of suspension as there are bicycle manufacturers. Retailers and others in the cycling biz pushed and prodded at the new models unveiled last week, asking tough questions and wearing skeptical looks.

“There was the stuff that worked, and then there was the stuff that was just so funny you just had to laugh and walk away,” said Feike Banning of Rainbow Bicycles in Laguna Beach.

Some makers have incorporated the suspension systems into relatively “normal” looking frames, while others have taken this opportunity to make some radical departures from traditional design. Because there is no consensus on how to make suspension work, approaches to the problem take on a bewildering variety.

The main design challenge is to overcome the basic knock against full suspension: that too much pedaling energy is absorbed by the suspension when the biker is climbing a hill. Another problem is the added weight of suspension.

Suspension’s biggest advantage is that it keeps the wheels in better contact with the ground, even on tough terrain, translating into better control and more efficient riding. There’s the comfort factor as well.

“What you’re going to see in the next couple of years is the reinvention of every sort of suspension tried since Victorian times,” said Richard Cunningham, a Placentia mountain bike designer who makes his own top-of-the-line Mantis custom bikes and also designs bikes for Japanese giant Nishiki.

Cunningham shared Banning’s assessment of many of the products on display at Interbike, saying many appeared to be hastily planned and untested attempts to get a product on the market quickly. “There’s a lot of trash out there, slammed-together concept bikes,” Cunningham said.

He had praise for some of the fully suspended bikes in the show, not only for his own Nishiki design but also for Mongoose, Cannondale, Specialized and Offroad. Banning also singled out Mongoose, Specialized and Cannondale, adding GT to the list. Both agreed that most designs fall under one of two main categories.

One kind, typified by the new Specialized FSR, is known as “active,” “full-time” or “pedal neutral.” In brief, the suspension works whether the rider is applying pressure on the pedal.

With suspension that is “reactive” or “non-active,” pedal pressure “locks out” the suspension, so the bike behaves essentially as a rigid bike would when climbing. An example is the Cannondale Super V. Both types have their adherents.

Banning said that many customers are following the development of full-suspension bikes but waiting to buy until more of the bugs are worked out. Some of the ’93 models pass the test, he said. Also, the weight on full-suspension bikes is dropping and becoming less of an issue.

Although full suspension is reserved for top-of-the-line bikes appealing to elite riders, front suspension forks are making deeper inroads into lower price bikes. Many makers are offering front suspension forks as standard equipment on mid-range mountain bikes with price tags as low as $450.

Front suspension is making some ripples in the road cycling arena as well. Earlier this year, a rider won an important road race with a Rock Shox front fork, which helped him reduce bouncing on the cobblestone streets. Rock Shox trumpeted the victory at its Interbike booth.

Other developments in the world of road cycling were subtle, compared to the tumultuous changes in mountain bikes. This year’s show saw a proliferation of frames made from titanium, an expensive metal that is very hard to work with but is the lightest of frame metals. Some say titanium frames are also the liveliest and most resilient metal frames.

Massachusetts-based Merlin Metalworks found itself alone in the titanium frame business a few years ago, but no longer. Although use of titanium in components has been on the rise for years, the titanium frame boom is fairly sudden. The price tag is stiff: an average of about $2,000 per frame.

The materials revolution continues on other fronts, with such composites as carbon fiber and metal matrix (a bond of metal and carbon fibers) a common sight. Specialized had some fun with its whimsical S-Works designs, producing an composite-framed off-road Penny Farthing bike (those old-fashioned bikes with the big front wheels). It was just for fun.

Ron Purdy, assistant manager of Performance Bicycles in Fountain Valley, was excited by the increased use of titanium frames for road bikes and also by the introduction of carbon fiber spokes, which are as strong as metal spokes and much lighter (and more expensive). Most of the evolution in the road bike business remains a battle to reduce weight, he said.

Interbike is the biggest bicycle trade show in the United States, and the “most important in the world,” according to Cunningham. Retailers got their first look at the ’93 models at the show, which gives the event the atmosphere of a giant candy store for cycling fanatics.

The economy crept into conversations and into trade publication articles, with reports of flattening bike sales and a demand from specialty retailers for more low-end product from the big manufacturers as a way of competing with general discount stores.

Many companies and stores in the United States are hurting, Cunningham said, but he predicted that because people in the business tend to love bicycling so much, most will find a way to hang on during the hard times.

“The bicycle industry is so isolated from the rest of the world,” he said. “They just remain in orbit around themselves.”