CL-C Low Ride: CFMoto concept reveals new take on age-old design

Chinese firm CFMoto launched their first cruiser model this year in the form of the 450CL-C and used their platform at the 2023 Eicma show to display a potential future development of the machine in the form of the CL-C Low Ride Concept.

It’s a striking bobber that cleverly uses a large number of standard components, making a future production version likely, but stands out thanks to a reworked version of an age-old idea, the girder front fork.

Girder forks are one of the oldest forms of motorcycle front suspension, pre-dating telescopic forks and often associated with bikes from the 1930s and even earlier, so suit the Low Ride’s bobber style, but CFMoto has rearranged the spring and shock to create a more compact package.

As on traditional girder forks the front wheel is slung between a pair of rigid castings – the ‘girders’ – that are immensely strong, particularly in the fore-aft direction to withstand braking forces that might flex a telescopic fork.

At the top, these are mounted on a pair of wishbone-shaped links that pivot on the girders at the front and on brackets mounted to a conventional steering stem.

Unlike the Hossack-style forks used on the Honda Goldwing and BMW K1600 models, where the steering pivot is at the front of the wishbones – leaving them and the front shock mounted firmly on the bike’s chassis – and the bars are connected via a linkage, this setup works more like the pre-war girder forks, with the entire wishbones and shock moving when you turn the bars.

Where CFMoto’s design really departs from tradition is in the position of the single front shock. Instead of being mounted vertically just ahead of the steering stem, where it’s found on most girder-fork designs, it sits horizontally and transversely, running across the front of the bike below the headlight, which requires the use of a neat suspension linkage, as seen on some racing cars.

On a normal girder fork, with a vertical shock, the lower end of the coil-over is attached to the girders and the upper end to the steering stem, so as the front wheel moves upwards, the shock compresses. With it mounted horizontally and transversely, that can’t happen.

Instead, CFMoto have used rockers, or bell cranks, and a pull-rod system with rockers at each end of the Öhlins front shock, pivotably mounted on the girders. Pull rods are attached to the upper, inner corners of those (roughly triangular) rockers at one end and fixed to the underside of the steering stem at the other.

When the suspension compresses, these rods rotate the rockers around their bottom mounting points on the girders and squeeze the front shock, which is bolted to the two rockers’ upper, outer corners, from both ends simultaneously.

The layout offers a couple of advantages. One is that the rockers can be designed to create a rising-rate effect – compressing the shock a relatively small amount as the suspension initially starts to move but increasing the amount of shock movement later in the suspension travel, making the suspension progressively stiffer.

It’s something most bikes already have in their rear suspension but few have at the front.

The system is more compact than conventional girder forks, so the shock doesn’t impinge on the placement of the headlight. Downsides? The girder fork has more un-sprung mass than telescopic forks.

Rocker and roll There are two rockers, shaped a bit like triangles with one point facing down, one at each end of the front shock. The bottom corner of each rocker pivots on the girder forks, the outer corners are bolted to the two ends of the shock.

Pulling power The inner corners of the two rockers – hidden behind the shock – are attached to short pull-rods, angled downwards and with their bottom ends connected to the underside of the steering stem.

Pivot points As the front suspension compresses, the girders and the shock move upwards and the pull-rods tug the inner corners of the rockers down, pivoting them towards each other and forcing both ends of the front shock inwards.

See the light The design allows the headlight to be mounted relatively low above the horizontal shock and set well back between the girders, something that a vertical spring would prevent.

Coming soon? Front suspension aside, the mechanical parts of the Low Ride concept, including the frame, the swingarm and the 40hp, 449cc parallel twin engine, are taken straight from the current CL-C 450, suggesting a production version of the bike wouldn’t be difficult to make.