As seen at Roc d’Azur last month, new French brand Motion is looking to bring back the much-loved, much-maligned parallelogram* suspension fork.Since mountain biking’s early days, companies like AMP and Girvin touted the precise-tracking and up-and-back travel benefits of parallelograms for front suspension use. Interloc Racing and USE improved on the idea with anti-dive geometry, while Muddy Fox and Whyte integrated their models into the frame.
But small brands like those mentioned often have difficulty keeping up with more established players in terms of distribution, damper technology, and manufacturing costs, while riders are often reluctant to embrace such visually unique products – factors that have led many of those companies to insolvency or self-preserving moves toward off-the-shelf designs.
Or maybe their ideas were just crap.
Either way, since the ‘anything goes’ 1990s, parallelogram forks have become a rare sight indeed.
So why bring back the parallelogram? Well the wheel path is a good reason – forks that allow the wheel move up and back are in theory better able to respond to bumps, especially square-edged ones. If properly executed, parallelogram forks can also exhibit quite good torsional stiffness, as widely-spaced pivots are theoretically better at fighting twist than a pair of braced telescoping tubes.
And then there’s the anti-dive part: under hard braking, telescoping forks have a tendency to dive into their travel, quickening steering and shifting rider weight forward at what could be considered the worst possible time (or leaning heavily on dampers to mitigate dive). Much like VPP-style suspension systems can be tuned to use chain forces to stiffen against the rider’s weight shifts, parallelogram forks can be designed to use braking forces for the same. The result, at least in theory, is a fork that maintains the bike’s geometry and front suspension action under braking.
There’s also the potential for quite light weights – Motion is claiming 1.5kg (3.3lb) for the planned CROSS cross-country model and 1.8kg (4.0lb) for the GRAVITY trail/enduro version. Those aren’t bad weights for 80-120mm 29er and 120-160mm 27.5 forks – though they do appear to be relying on a largely composite construction to keep weight in check. Suspension in both cases comes from a pair of carbon fibre arcs, interchangeable for rider weight and desired travel. Dampers are housed in the head tube and, at least on the GRAVITY, can be adjusted via the neon green knob that can be seen at the stem cap.
As for Motion, the newly-formed company is dedicated to the principles of innovation, quality, performance and durability as well as the concepts of discovery and nature preservation, sports, well-being, respect, sharing, and self-transcendence.
Founder Matthieu Alfano is also committed to French production, which likely accounts for part of the forks’ forecast 1,920€ (£1,410) sticker price. The CROSS and GRAVITY are scheduled for late-2016 release, however those looking to get in on the action early can (until 31 October) apply to be members of a prototype test team to provide feedback prototype forks’ performance.
Programme PRECURSEUR, presumably limited to residents of France, requires a 1,000 (£735) deposit, which is refundable on return of the fork or can be used for its purchase at the end of the program. Given the number of companies accused of using their customers as beta testing, we suppose that it’s nice that one is being up-front and offering a discount for the practice.
Does it work? Caminade (whose French-made steel full suspension bikes we’ve featured previously) seem to think so, saying (roughly) The dynamic behavior of the prototype fork turned out to be beyond our expectations, with sensitivity and progressiveness important for comfort and grip, and the ability to keep 100% of the usable travel even on heavy braking… The fork had lightness combined with good stiffness too. So they liked it.
One of the beauties of the bike industry is its attractiveness to quite bright people (who could often find a far better living elsewhere) and their unique visions. Many designs prove to be expensive novelties – but every once in a while something breaks through and makes riding better for everyone. It will be interesting to see where Motion falls between these poles.
*not necessarily a parallelogram in the strictest sense, but for the sake of simplicity…