ANAHEIM, CALIF. - Plastic applications continue to grow, but exhibitors at the Interbike international bicycle expo displayed fewer material innovations than a few years ago. Douglas Cusack, an engineer with Trek Bicycles in Waterloo, Wis., saw more thermoplastic applications on display. He tries to use the different advantages of thermoplastic and thermoset materials in Trek developments.
Bicycle component supplier Shimano Inc. of Osaka, Japan, "avoids exotic materials" and tries to improve performance of its race-group Dura-Ace line through engineering, according to Wayne Stetina, product manager with the Shimano America unit in Irvine, Calif., and a former Olympic racer.
Fred Teeman, vice president of team merchandising for Giant Bicycle Inc. in Rancho Dominguez, Calif., saw more uses of carbon fiber at lower price points and leans toward carbon over titanium for critical parts.
``I see a continuation in use of carbon fiber,'' said Jeffrey Heininger, president and chief executive of Softride Inc. in Bellingham, Wash.
Specialized Bicycle Components of Morgan Hill, Calif., will offer a dual-suspension mountain bike with a resin transfer molded carbon-fiber internally ribbed backbone and an aluminum alloy pod.
``The blend creates the strength we need,'' said Chris Murphy, marketing director.
Once again, composites seek to penetrate the market for high-performance crank sets. Four companies displayed versions of polymer-matrix-composite crank arms. Other manufacturers questioned carbon's durability.
Storck Bike-tech Trading GmbH makes carbon-fiber crank arms and, in the first year, sold 400 of the high-performance $700 units, mostly in the German market. The arms are used with regular spindles and Shimano chain rings.
Markus Storck, general manager of the Bad Camberg, Germany, firm, said he is making the world's first production carbon crank. He has persisted beyond the efforts of ``six or seven other companies,'' Storck said. ``They drop the products because they are time-consuming.''
Quality Composites Inc. molds an oversized Styff-brand crank and spindle in a proprietary process with Fiberite Inc. standard-modulus carbon fiber.
``We have a composite spindle and made the diameter seven-eighths of an inch instead of a half-inch,'' said Peter Travasono, chief executive officer of the Sandy, Utah, firm. The unit will be available in 1997 and sell for about $500.
Via Tech Inc. in Tempe, Ariz., is accepting orders for its $429 High Zoot-brand cranks that are made with solid carbon fiber laminate and attach to regular spindles. ``We have been working on the crank for the last year,'' said Chris DeLap, general manager.
Cannondale of Georgetown, Conn., displayed a crank arm that has machined aluminum spines and carbon fiber skins.
Others wonder about the application. ``Traditionally, crank arms are made of aluminum or forged aluminum,'' said Trek's Cusack.
Keith Bontrager, for one, avoids composite crank arms.
``We're not optimistic about that kind of assembly'' because the application is ``not optimized for that material,'' said the president of Bontrager Cycles in Santa Cruz, Calif.
``There are few areas where bicycle is attached to rider, and failure in those areas is a significant thing,'' Bontrager said. ``Because of bonded assemblies, it doesn't look like the designs are sorted out. It's not the right direction.''
An after-market supplier also was skeptical.
``I have concern about notch sensitivity and durability of carbon-fiber crank arms,'' said Mike McCall, manufacturing engineer with Cook Bros. Racing in Arroyo Grande, Calif. ``Will carbon fiber hold up on mountain bikes that take a large amount of abuse?''
McCall said high-end aluminum crank sets retail for $150-$200 and alloy steel tubular cranks, for $300-$400.
The Sept. 19-22 Interbike expo in Anaheim featured 912 exhibits and attracted 21,115 attendees.