Do you still remember Aaron Gwin's sensational winning run at the Downhill World Cup in Leogang? Back then, the American's chain snapped as he sprinted out of the starting gate. But instead of cancelling the run, Gwin pushed himself over root patches, jumps and through the bends as if unleashed. At the end of the run, he raced through the finish arch with the fastest time. Since then, the bike world has been puzzling over whether the missing chain was actually an advantage for the downhill pro. The thought behind it: Without a chain, the chassis could move more freely and therefore work more effectively. The special Spider Ochain R chainring aims to utilise the same effect. It allows the chainring to move backwards a few degrees, which should prevent the chassis from hardening and pedal kickback.
Ochain R - the data at a glance
- Material 7075 T6 aluminium / 6082 aluminium / stainless steel 316
- Offset 3 mm (6 mm / 7.5 mm with Ochain Kit)
- Chainring standard BCD 104, oval chainring compatible
- Compatibility Sram, Shimano, Hope, Raceface
- Colours Silver, black
- Weight 150 g
- Weight limit 120 kg
- RRP 385 EUR
Ochain R - the idea behind it
MTB designers deliberately use chain forces to prevent the suspension from being sucked into the suspension travel when accelerating, for example with the help of anti-squat. The downside of this effect is pedal kickback. When the suspension compresses, the rear triangle elongates, causing the crank to rotate slightly backwards. The rider perceives this as a slight bump in the foot. In addition, the suspension hardens - not exactly sensible when you're rattling downhill.
Ochain wants to prevent this effect with its spider. This is screwed between the crank and chainring and allows a certain amount of movement of the chainring via springs and elastomers. The slight freedom of rotation backwards is intended to compensate for pedal kickback.
New: simple adjustment using an Allen key
The disadvantage of the previous system was that the spider had to be dismantled to adjust the degree of freedom. The conversion took time and required a clean work surface. Because when changing the elastomers, which define the degree of freedom, it was important to prevent the system from getting dirty. Different set-ups during a downhill training run or an adjustment on a long trail descent were therefore not possible. With the new Ochain R Spider, the angle can now be easily varied between 4°, 6°, 9° or 12° on the trail using an Allen key. This makes it easy to try out the different settings on the go and adapt the bike to the conditions of the trail.
To adjust, simply turn back the black nut in the spider and then select the different angles using a central screw on the spider. Lasered lines help you to find the right setting. From the inside, the change is made via a movable cogwheel that changes the "starting point", so to speak.
A stroke of genius or hocus-pocus? How well the Ochain spider actually worksWe have already checked this in an extensive test.
The new Ochain R Spider is now available for 385 euros for the crank standards ofSRAM, Shimano, Raceface and Hope.
Stefan Frey
Editor
