Monoshock

A monoshock replaces the pair of rear shock absorbers with a single, larger unit mounted close to the centre of the bike. The rear wheel is carried on a swingarm that pivots on the frame just behind the engine. The shock connects the swingarm, either directly or through a linkage of rocker and rods, to a mount high on the frame under the seat. Almost every sporty Indian motorcycle uses one, from the Bajaj Pulsar NS200 and TVS Apache RTR 160 4V to the KTM Duke range and the Royal Enfield Himalayan, as do electric scooters such as the Ather 450X.

• The rear tyre hits a bump and the swingarm swings up about its pivot.
• The swingarm pushes the shock, compressing the coil spring and forcing oil through the damper valves.
• With a linkage, the rocker changes the leverage as the wheel rises, so the spring effectively gets stiffer the further it is compressed: a rising rate.
• The spring returns the wheel while the damper controls the speed of return.

A rising rate is the monoshock's great advantage: soft over small ripples, firm enough not to bottom out over a big pothole or with a pillion. Mounting one unit near the centre of gravity also frees space at the back for a slim tail and lets the shock be bigger and better cooled. The rider notices a planted rear in corners and fewer bottoming thumps on bad roads. Linkage bearings need periodic greasing, and a single shock has to be built well, since there is no second unit to share the work.