07.25.2007 - Bicycle Newswire
Bike designer Kirk Pacenti is into big wheels. He was riding 700C
and 700D wheels in the early 1990s, has been a long-time proponent of
29ers, and probably even rode one of those plastic "Big Wheel"
tricycles as a kid. But now he has seen the MTB future and the wheel
size is 650B.
With 650B wheels (which measure 27.5" in diameter, half-way
between 26" and 29" wheels), full-suspension bikes can be produced with
4" to 6" inches of travel and throughout a wide range of frame sizes
without abandoning proven 26" wheel frame geometry.
650B wheel bikes can be designed for a wide variety of uses from XC racing to 4X and DH racing.
650B wheel bikes can accommodate riders 5' 3" to 6' 4" tall or more.
650B wheels offer great obstacle roll-over capabilities for a smoother ride.
Consumers are already demanding 650B bikes and bike designers are producing the bikes.
"What I believe 650B wheeled mountain bikes will allow builders to
do, is to utilize proven 26 inch wheeled geometries, coupled with the
largest wheel possible in a bike with little or no geometry
compromises," says Pacenti, president of Pacenti Cycle Design, which
supplies product and support to frame builders. "As 140mm travel bikes
become the norm (even for XC bikes) the 650B wheel size is going to
make even more sense."
Granted, the biggest obstacle to any new wheel size is tires, but
Pacenti has already covered that rocky ground. A Pacenti-designed and
branded Panaracer-made 650B tire - the Neo-Moto - is currently in
production and will be available by mid-September. In addition, White
Brothers is producing suspension forks for the new wheel size, and
Velocity USA, which has built 650B rims for the bicycle touring market
for years, is already in production of their new "Blunt" all-mountain
Because the 650B wheel size is compatible with many 26" wheel
components numerous parts are already available. For instance, Maverick
forks can be easily optimized for 650B wheels with a travel reduction
kit, and some current 26" and all current 29" disk specific suspension
forks will work with the 650B wheel size.
But what's a wheel and parts without a frame. Numerous independent
bike designers are fully embracing the new 650B wheel size and
producing 650B frames. The current list of frame builders includes:
Ahrens Cycles Carver Bikes El Camino Fabrication Engin Cycles Independent Fabrication Kent Eriksen Origin 8 Pacenti Cycles Rawland Cycles Rivendell Rock Lobster Cycles Siren Cycles Soma Tomac Mountain Bikes Turner Suspension Bikes Vicious Cycles Walt Works Willits Brand ZR Cycles
Noel Buckley of Knolly Bikes, who understands the impact wheel size
has on full-suspension frame design, says: "Kirk's forward thinking
vision is correct in that 29'er wheels don't work well for frames with
more than 100mm of rear travel. While working on the design of a 29er
version of our new Endorphin frame, we started realizing that serious
compromises would need to be made to the frame geometry due to
undesirable forward wheel paths, chain stay lengths, and BB height all
caused by the large 29" wheel diameter.
"Kirk knows what he's talking about. The 650B wheel size makes more
sense for a company looking to produce big wheeled bikes in the 100 -
150mm travel category because they get the rolling benefits of the
larger tire, but don't have to modify frame geometries much, or have to
contend with the design compromises imposed by 29 inch wheels."
As many as a dozen manufacturers will have 650B parts and components
ready for this year's Interbike trade show and distribution of the new
Pacenti 650B tires will be handled by a number of well-known
distributors. (A list of distributors will be available soon.)
"I am fully committed to the 650B wheel mountain bike," says
Pacenti. "I have been receiving daily inquiries from custom builders
and even consumers who are very interested in the wheel size. Support
for this project has been overwhelming. I truly believe 650B wheel
bikes have a bright future in mountain biking."
About Pacenti Cycle Design
Kirk Pacenti founded Pacenti
Cycle Design for the sole purpose of supplying and offering support to
the artisans who build quality hand-crafted bicycle frames. He provides
particular dedication to lugged steel construction but is expanding his
product offerings to include all materials and construction techniques
including the new 650B wheel bike. For more information call (423)
954-3373 or log onto the Internet at www.bikelugs.com.