Feature Article

TECHNOLOGY ON TWO WHEELS: A NEW ERA OF

Prashant Raghav

OTORBIKES are coming of economic commuters, destined to be the last decade in India. age today. They have evolved frugal, and having just enough grunts Let’s take a peek at some of Mleaps and bounds from the to get people and some luggage within the fascinating technologies that the first ‘true’ introduced just neighbouring localities. However, with motorcycling world packs under its over a century ago, in 1885 by Gottlieb increasing economic development as well belt today. Amazingly, a few of these Daimler. as global technological exposure, high- features are still not available on our In India, motorcycles have end performance and luxury motorcycles average family hatchback, let alone a traditionally been deemed as mere seem to have been finally welcomed in motorbike!

26 | Science Reporter | August 2018 The majority of the largest touring speed limit. However, over the course of motorcycles weigh roughly around 350- the last few years all across the globe, 400 kg. Hence, pushing them backward traffic population has increased multifold with just muscle strength is not an easy reducing the average traffic speed feat. Therefore, a reverse gear employed considerably. Nevertheless, select niche on these heavyweights is more about motorbike brands still offer this opulent functionality than luxury. option on their flagship models, often Often, it is not actually a reverse costing upwards of INR 20 lacs! gear but simply a feature of the starter On a motorbike, the rider reaches motor that performs the same function a certain speed and presses the ‘Cruise when switched to reverse. To avoid Control’ switch on the handlebar. The accidental operation, usually there is bike then holds the desired speed and the a separate or two-step mechanism to rider can take his arm off the ; of engage the reverse – the motorcycle course, he/she still needs to balance the needs to be in neutral first. bike. Since it is a highly sophisticated, The method of engagement is precision- oriented technology, for rather simple; in some bikes, there is a optimum working of cruise control the separate, hand-operated lever installed motorbike must have ‘Ride-by-wire’ and on the motorcycle which engages the ‘Electronic Fuel Injection’ technologies. reverse gear. On other, newer models, Cruise control is widely deemed as there is often a dedicated ‘Reverse’ a luxury feature rather than a utilitarian switch mounted on the handlebar along one. Hence, it is mostly employed on with other standard controls. However, high-end luxury bikes meant for long the speed in the reverse gear is just distance touring or highway cruising. about walking pace, since motorcycles are not stable when ridden in backward Anti-Lock Braking System (ABS) Photo by Pok Rie from Pexels direction. The reverse gear is particularly Modern superbikes can accelerate from helpful while pushing the bike backward naught to a hundred kilometres an hour on a slope or uneven surface. Reverse Gear in just about three seconds. However, it You read it right! Many reputed all comes down to the braking prowess motorcycle brands have been offering Cruise Control and technique in life or death situations a reverse gear on their flagship cruiser A cruise control is an electromechanical while on the road. Matters get worse motorcycles for years now. This is mechanism in a vehicle that allows you when driving on susceptible terrains primarily because to drive it without giving the throttle like wet or curvy hill roads, as there is the weight yourself; it holds the throttle for you at nominal grip. of such your desired preset position. First introduced on a production machines is Initially, cruise control was motorcycle back in 1988, the Anti-Lock normally developed to make long distance Braking System is often regarded as one around journeys less tiresome for car drivers of the most indispensable features in a three times like the ones on the American inter- motorcycle. the standard states or the German autobahns, where ABS works on the principle of motorcycle. the highways are wider and straighter ‘pressure modulation’ – it regulates the and a lot of areas don’t have a maximum applied brake pressure or brake force

August 2018 | Science Reporter | 27 ABS works on the principle of ‘pressure modulation’ – it regulates the applied brake pressure or brake force with respect to the speed of the vehicle and the speed of the wheel it is acting upon.

with respect to the speed of the vehicle professional can brake equally or even respect to the road surface conditions, and the speed of the wheel it is acting better than ABS using a technique known TCS gets activated. It modulates or upon. With the help of sensors, it as ‘cadence braking’. This technique regulates the throttle according to the monitors these two speeds independently involves pumping the brake pedal to vehicle dynamics as well as surface at a very high frequency, about 10- allow the vehicle to both steer and brake conditions, to provide maximum 15 times a second depending on the on a slippery surface. It is used where traction under all situations. Generally, manufacturer. It then modulates the traction is limited, to prevent locking up TCS employs various techniques of pressure of going to the brake and skidding of wheels under hard or intervention like applying brake force piston in the calipers using actuators, emergency braking. to individual wheels, reducing fuel relays, and bypass valves. supply to the engine, closing the throttle electronically, etc. Although theoretically, ABS Traction Control System (TCS) should prevent wheel locking under In high-performance and racing A Traction Control System (TCS) is all conditions, in reality it does allow bikes, TCS prevents spinning of the rear designed to prevent loss of traction of some degree of wheel slip in order to wheel under hard acceleration, especially driven road wheels. It can be considered achieve maximum braking efficiency. in wet, icy or snowy conditions. as a subunit of the Electronic Control The working of ABS is like applying Moreover, while accelerating out of a Unit (ECU) which is also known as the the maximum brake force and then corner, it keeps the tires at an optimal brain of a vehicle. releasing it just before the wheels lock, slip ratio. and repeating this mechanism at a rate of TCS is also a secondary function of Many sports bikes have TCS as about 10-20 times per second! the Electronic Stability Control (ESC), standard with multiple modes that can also known as Electronic Stability In general, for a novice driver, be changed on the go, for example Program (ESP). Generally, Traction Rain, Sport, Track etc. The essential braking with ABS might be quicker and Control System shares some components difference between these modes lies safer than without it if the road surface is with the ABS, like the electro-hydraulic in the degree of intervention, with the clear and dry. brake actuator and wheel speed sensors. Track mode allowing more wheel spin However, there is a critical flip In a motorcycle, TCS controls the or power-sliding for a more dynamic side to this anti-locking mechanism. flow or delivery of power from the engine or sporty style of riding, while the Rain Contrary to popular misconception, the to the rear wheel. When throttle input mode limits the throttle feed under even primary function of ABS is not to reduce slight wheel slip for more stability in wet braking distances, rather it is meant to and engine torque are mismatched with prevent locking of wheels under sudden or heavy braking thereby increasing maneuverability in emergency situations. Therefore, the braking distances are relatively more with ABS on surfaces like snow and gravel. In fact, on such surfaces skidding may help the tyres to dig into the surface and stop earlier. Often an experienced rider or a

28 | Science Reporter | August 2018 conditions. You can also choose to turn or shift down more than one gear As depicted with an ‘H’ image on the off the Traction Control completely, if altogether, especially in wet or slippery gear knob of a car, the gears are not in the settings allow. surface. These phenomena are usually a sequential order but are jumbled up. observed in high compression engines However, on a typical motorcycle, Slipper wherein riders can clock speeds in the first or second gear can be selected About twenty years ago, slipper excess of 150 km/h. directly from neutral, but the rest of were reserved for race bikes. the gears (third and beyond) can only These days, they come standard on all Bluetooth Connectivity be accessed in a sequential order. kinds of street bikes from performance A pretty common feature in cars, Hence, unlike in cars it is not possible machines to beginner bikes, and even Bluetooth integration function is to shift from second gear to fourth sport-tourers and cruisers. steadily picking up on two-wheelers gear without shifting through the third Also known as a back- as well. Many gearless scooters, for gear. Automatic transmissions are far torque limiter, slipper clutch is a example, are available with Bluetooth less common on motorcycles, and are specially designed clutch developed connectivity. mostly found only on gearless scooters for performance motorcycles to and some exotic luxury bikes. Motorbikes are not far behind, mitigate the effects of engine braking and the functioning remains the same. There are three basic types of under sudden or hard deceleration, Just as we attach two individual devices automatic transmissions that are particularly while entering a corner. through Bluetooth to share files (for generally employed – continuously Known as the ABS of the drive instance, two mobiles, a mobile and variable transmission, semi-automatic train, slipper clutch helps by allowing a laptop), similarly one can connect transmission and dual clutch the clutch to partially slip or disengage a mobile phone with the motorbike’s transmission. when the rear wheel rotates faster than Bluetooth module using an adapter. Usually preferred for high-end the transmission usually does, until the The basic purpose of a Bluetooth touring bikes and cruisers, automatic engine speed matches your own speed. feature on a motorcycle is to provide transmission on motorcycles are In a normal clutch, the engine braking remote, hassle-free mobile connectivity mostly semi-automatic or dual-clutch force gets transmitted to the rear wheel to the rider without having to operate type. Whereas Continuously Variable via chain-sprocket mechanism (or shaft the mobile itself. Mostly, a separate Transmissions (CVTs) are almost drive in select motorcycles) which can Bluetooth earpiece has to be fitted in exclusively used in gearless scooters. cause the rear wheel to tremble, hop the helmet in order to access calls and Dual Clutch Transmission (DCT) is and lose traction. voice functions. basically a clutch-less shift where A slipper clutch provides smoother However, another trend has been you can either change gears manually downshifts, particularly when shifting to connect the mobile for playing with the help of a switch or button, down more than one gear at an music through loudspeakers installed or else choose to ride in automatic instant, preventing your gearbox and on the motorbike. This is particularly mode. Consisting of two clutches for engine from catastrophic breakdown. common on massive touring bikes and odd and even gear sets, DCT can offer It is particularly helpful on higher luxury cruisers, which offer integrated excellent fuel economy. The biggest displacement bikes where the engine multimedia and entertainment options advantages they have are ease of use braking force is massive and may cause on board. and convenience. the motorcycle to go out of control, While most of these features resulting in a high-speed mishap. remain restricted to high-end, Automatic Transmission In a racing environment, while performance and luxury motorcycles, riding at higher speeds and cornering, Most modern motorcycles change consumer demand and evolving riders need to brake hard and shift gears via a foot lever and technology might someday bring these down 2-3 gears at once. This causes predominantly employ a sequential kinds of features on our ‘average heavy engine braking and the rear manual transmission for the job. commuter’ motorcycles. So, the next wheel spins at a higher speed than the The difference between the standard time you spot an exotic motorbike on transmission. It might lead to friction manual transmission used in cars and the road, remember it’s as much about in the clutch and ultimately damage the sequential manual transmission technology and features as much it is the clutch, gearbox and the whole used in motorcycles lies in the gearshift about looks and speed. Ride safe! transmission assembly, but most of all pattern. put the rider at risk. Essentially, in a car you can Prashant Raghav, Research Intern, Even during city riding, a slipper jump from the first gear to the third, International & Popular Science clutch could prove to be a salvation or second to the fourth and vice-versa Division, CSIR-NISCAIR; Email: when you downshift accidentally without going through the neutral gear. [email protected]

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