INTRODUCING

The Coal rear linkage is a TLFS (Twin Linkage Floating Suspension) design with a fully floating shock combined with a twin rocker. The design delivers a linear, progressive shock curve idea for coil or large volume air canisters.

The benefits of the design mean a fully active suspension even in the hardest of braking situations allowing the rider to push harder in more challenging lines and terrain. this set up also provides great peddling efficiency on climbs sprints and smashing though rock gardens, all this while maintaining sensitivity and support for the rider.

This bike also benefits from a flip chip. The chip will lift the BB and increases rear travel to 170mm and is designed to allow the bike to be run with a 27.5” rear wheel with a 2.5 rear tyre. It also makes the rear suspension more progressive reflecting the mixed wheel focus on freeride and fun.

The twin rocker linkage delivers a slightly rearward axle path resulting in the first 100mm of rear travel being nearly completely vertical. This means the bike is fun, but also stable, and doesn’t get hooked up on big hits, yet this design minimises pedal kickback.

And the best fun part is you get all this and the ability to go mullet and increase the travel by 10mm and run the bike mullet with a more progressive feel for the big bike park hits.

We believe this has made this bike to be one of the most versatile capable fun bikes available in the uk.

29er Leverage ratio.

Mullet leverage ratio.

The shock has been positioned inside the front triangle as close to the BB as possible to centralise the mass and keep it protected as well as provide space for a large water bottle and minimise stand over height. The fully floating shock and progressive linkage gives the best possible small bump sensitivity by reducing breakaway friction with a dual bearing set up. Reynolds steel tubing has been used in the front triangle and rear swingarm and matched to large stiff 6082 aerospace grade aluminium linkage's, to deliver an ideal lateral to longitudinal stiffness ratio. The steel tubing providing compliance when the bike is learnt over, the twin large aluminium linkage's provides stiffness when taking big hits.

The front and rear have been designed utilising FEA to ensure weight is kept to a minimum and strength is assured. Covered oversized Enduro MTB specific bearings are used to ensure good endurance even against the worst UK weather.

The geometry is set to position the bike to be fast and stable but still agile and fun. The seat tube angle of 76 degrees backs up that this really is a bike for bike parks, races and all-day adventures. Head tube angle is at 64.5 degrees with the flip chip in high mode or with the flip chip in low the head tube angle is at 63 degrees, there are also two more flip chips that allow for intermediate settings between high and low.

The bike has been designed in-line with modern long, slack and low ethos, but has been designed to be flexible with the flip chip, allowing it remain playful, all this paired with a short chain stay length of 440.

The bike has been a collaborative effort over 2 years in development. The goal was to create a steel bike in the UK that had the potential to both win an EWS race and be fun at the weekend at uplift parks, as well as pedal around your local loop. We wanted to create something with a state of the art linkage and that had the geometry and weight to take on the best bikes in the world.

Gavin the founder of coal bikes and former Stanton welder and fabricator provided the knowledge on the frame material choice, welding and fabrications. Alex from Dezmotoracing Ltd provided the design, engineering and FEA, and Paul from Rideworks provided the top shelf CNC components and linkages. The whole bike has been designed, manufactured and tested in the UK.

Anti-squat.

Magnified axle path.