When we discuss about a motorcycle's performance, we generally speak about its engine power, torque, top speed, how fast it can accelerate, vehicle sound etc. Nevertheless, all these are meaningless if a driver cannot control the machine and/or is not comfortable while riding. There comes the importance of tyres. Tyres are the most crucial parts of a vehicle suspension system.  Tyres are the only component in a motorcycle that constantly stays in contact with the road. The part of tread which is in contact with road surface is called ‘contact patch’ & Is about half the size of a post card.  The overall suspension system (including tyres) ensures the right contact between the tires and the road surface at every stage of driving, thereby ensuring stability and good handling of the vehicle.

As tyres are the only contact with the road, they are responsible for multiple functions, such as –

Transfer the engine power to the road- meeting the demands of acceleration and braking

  Provides right hold (grip) on different surfaces like dry, wet, snow, loose soils etc.

  Helps the rider to steer the vehicle by responding to the handle movements

  Carry the weight of the vehicle & rider

 Ensuring the comfort of the rider by absorbing and dampening shock

Apart from the above aspects, tyres play a vital role in vehicle aesthetics, safety, fuel efficiency etc. These and several other challenges make Motorcycle tyre design a very interesting and responsible subject.

Apart from being a crucial part of a vehicle suspension system, tyres are the only contact between vehicle & road. Motorcycle vehicle dynamics and control characteristics are highly influenced by the tyre design. It is therefore highly imperative for a vehicle chase/suspension designer & tyre designer to work together in tandem. This will ensure that the part designs will complement each other and deliver the characteristic target performance of a motorcycle. A robust interaction mechanism between the R&Ds of OEM [Original Equipment Manufactures] and tyre manufactures is a growing necessity to cater to the ever‐increasing demands of performance entrusted upon the tyre of today. In case of tyres getting designed exclusively for aftermarket, a tyre designer work closely with the vehicle dynamics team to ensure that the retrofit design delivers desired target performance of the vehicle

Some of the major steps involved in motorcycle tyre design are

 Product planning & Tyre “Size” finalization: During this stage a vehicle designer & tyre designer jointly review the vehicle performance requirements and decides the parameters specific to tyre performance. This includes:

Defying the application /terrine: Depending on application, 2 wheelers maybe broadly classified as Sport, Cruiser, Choppers, Touring, scooter, Step through, Sport touring, Enduro etc. Different OEM’s follow different terminologies, but a for a tyre designer to understand the final use by the user is of utmost importance. Demands from a tyre varies with each vehicle category, for example, for a cruiser the tyre is designed to be robust so as to hold up the weight of such heavy bikes and deliver long tyre life, whereas for a Sport touring /super sport bike, tyres are  designed to deliver quick and precise handling with superior grip. These tires are lighter and made by using softer compounds for Superior grip.

Selection of Bias /Bias belted / Radial:   At this juncture, I am not going to delve deeper into a detailed comparison of these constructions – however, it is important to acknowledge that both these construction types have their respective advantages and disadvantages. Each of these constructions has few specific applications where one performs better than the other. The selection of construction type mainly depends on vehicle category (application), vehicle Speed, load on the tyre, stability requirements, handling requirements, etc. for example Bias tyres are used in medium speed but heavy weight vehicles owing to their sturdy sidewalls, whereas Radial tyres are the ideal choice for high speed , vehicles because of their superior dimensional stability.

Selection of Tube type Vs Tubeless:  Functionally both types of tyres have a proven track record for almost all applications. Hence this choice mainly depends on vehicle Rim design, which is decided by the overall aesthetic demand & application of the motorcycle.For high speed application, tubeless is always preferred

Finalizing the Tyre size / Tyre Geometry:  In general, we may call it as tyre “size” – which includes tyre width, tyre diameter, rim diameter etc. Tyre geometry affects the vehicle dynamics like caster, trail, vehicle Center of gravity [CoG], etc. It also influences the area of contact between vehicle and road surface under different riding conditions & load-carrying capacity of the tyres. Furthermore, tyre size significantly influences vehicle aesthetic as well.  Tyre “size” and vehicle rim size are always interconnected. Decision on one influence the decision on the other.  Usually motorcycles have different front and rear tyre sizes depending on vehicle geometry & load distribution. Tyre “sizes” are decided considering all these parameters & the designers ensures that it follows the standards’ guidelines applicable in target countries.

Tyre tread profile design:

Contrary to the passenger car tyre designs which have almost flat tread surface, motorcycle tires have a U-shaped profile and a contact patch that changes size and shape during cornering. There is a major difference in the way lateral force is built up in passenger car and two wheelers.  In case of passenger car, mechanism of lateral force builds up is due to slip angle whereas in two-wheeler it is mainly because of the camber or the leaning of the vehicle.  Hence you see a flat tread area for passenger car tyre and U-shaped profile for Motorcycle tyre

This U-shaped profile is an important design factor having a direct influence on vehicle performances such as drivability (handling) durability, ride comfort, noise and wear resistance etc.

These tread contours are designed as the arc of one radius, or a combination of arcs with two or more radii. These profiles ensure the required contact patch availability at different lean angles & are controlled by the lean characteristic of the vehicles. It is very critical to balance the performance of front tyre & rear tyre of s motorcycle for precise handling of the vehicle. The contour designs play an important role in front /Rear tyre balance.

Tyre tread pattern design:

Patterns are molded in the tread area of tyre by repeated arrangement of ‘Groves’ or ‘Blocks’ & are generally referred to as “tread pattern”.

Significance of tread pattern: 

Tread pattern plays a vital role in tyre performance such as:

Optimizing the traction on the riding surface

Eliminating aquaplaning

Optimizing the” Wear” of tread area·  

Ensuring the continuity of tyre performance at different wear Stages [ wear %] of tyre.

Rolling resistance of the tyre

Noise generation

roviding a measurable clue to the owner on time for removal /suitability for continuous usage. etc.

Tread patterns not only helps in achieving the target performance, but also impart unique look to tyres and enhance aesthetics

Tyre patterns are broadly classified into 4 Major headings

• Rib patterns
• Directional
• Block [ Knobby]
• Slick tyres [Pattern less]

Selection of which group of patterns is mainly controlled by the terrain of application, e.g. Directional patterns are preferred in paved roads and knobby pattern ae mainly used on off-road applications. Pattern less tyres are normally used in racing track applications to provide maximum traction.  Vehicles are designed to work in a combination of different terrains – similarly, tread patterns also have subgroups– which are optimized to operate in different combination of terrains. E.g. Semi knobby patterns for on – off allocations, High land – minimum grove patterns for Supersport highway applications etc.

Designer alter the direction of the grove, depth of the grove, number of groves, the ratio between Grove area & non grove area [ Land- sea ratio] , shape of the grove, the width of the grove etc. to optimize the performance of tread pattern. These patterns are designed to perform under different dynamic conditions. Nowadays designers seek the help of computer-aided simulations to predict the performance under different loading /riding conditions to optimize the pattern design.

Tyre as an Aesthetic component

The visual appeal of tyre is significant contributor in the overall aesthetics of a motorcycle. Hence in addition to performing all the functional requirements discussed so far, tyres ought to look good too.

The tread pattern should complement the overall styling language of a motorcycle. This attracts the attention of OEM’s vehicle styling studios towards tyre tread designs as well. In fact, most of the new tyre designs are done first at styling studio and then technically optimized by the tyre engineer to guarantee the functionality.

Material design

Tyre is a composite material made of different rubber compounds and reinforcing materials. Right compound and reinforcing material selection are crucial to achieve the target performance of tyre.

• Reinforcing materials:

Reinforcing materials provides the required strength and stiffness for tyre body [carcass]. This includes “tyre cords” used in tyre body ply & “bead wires” used in bead construction of tyres. Most used tyre cord materials are Nylon 6, Nylon 6-6, Polyester, Aramid, Rayon, Steel, etc.

These materials differ in their chemical composition, tensile strength, elongation properties, impact strength, temperature resistance, rubber adhesion, etc. Tyre engineer must choose the right tyre cords depending on the performance demands of the tyre like load carrying capacity, durability, impact resistance, drivability, speed of operations etc. Cost & availability also are few decisive parameters during selection of reinforcing materials.

Tyre Cord denier, cord style, EPI (Ends Per Inch), angle of cords and number of plies affect the strength of a tyre and are chosen based on engineering, and design criteria.

structural durability of a tyre is Primarily determined by the reinforcing material

• Rubber compound design

Each part of the tyre must dispense different functions and are thus designed with different rubber compounds like tread compound, sidewall compound, carcass compound, bead wire coat compound, etc.  Though all these compounds have their own importance, but tread compound selection is the most critical, as it has a direct impact on tyre traction, handling, wear performance, durability, rolling resistance, etc.

• • Trends of tread compound design:    

Even though smaller number of components are used in a motorcycle tyre, than as compared with passenger car tyres, but performance challenges involved in compounding are far more complex considering less area of tyre in contact with road. 3 major performance requirements in motorcycle tread compound are (1) Grip (2) Rolling resistance [fuel efficiency] and (3) Tyre life which is generally referred as the magic triangle in tyre rubber compounding. This is due to the contradictory response of these 3 performance characteristics to rubber compounding approach. For example, improvement in Grip normally comes with an increase in rolling resistance with conventional compounding as both are related to energy loss. It is always a challenge for tyre compounder to improve all three performance requirements together and this calls for the incorporation of advanced polymers and fillers.

Performance priorities for tread compound changes based on operating terrain, type of vehicle, etc. e.g. Street two-wheeler tread compound designs primarily focus on high grip and high-speed capabilities, whereas an on-off application tyre require higher cut and chunk resistance tread compound.

Demand for lower rolling resistance tyre is showing a steady increase Year-on-Year. Major divers for this growing demand are Electric vehicle introduction & increased focus on vehicle fuel efficiency, in few segments. Tread compounds are expected to deliver lower rolling resistance, without compromising the Grip – typical “magic triangle” puzzle for any tyre compounding engineer. Tyre industry can address this challenge by usage of new generation materials like SSBR, functionalized SSBR, high molecular

Design for manufacturing

For success of any product – Design & manufacturing sync is a must. While designing, to accommodate all functional requirements, a designer cannot ignore the significance of manufacturing process. Hence every tyre design is optimized to satisfy both functional & manufacturability needs. This if not done properly may result in suboptimal performance of the product,

Product Performance Testing

It’s important to review and verify the product performance before releasing it into the market. There are a set of Indoor & Outdoor tests for performance review. A few of them are listed below,

Indoor tests: High-speed drum test, Endurance test, Rolling resistance test, Force and moment testing, Stiffness test, Footprint etc.

Outdoor tests: Ride and Handling testing (track, off-road, public road etc.], Braking test [wet, dry], tyre wear test etc.

Blend of Engineering & Art

Being an integral part of vehicle suspension system & only contact point with road, a tyre plays significant role in motorcycle performance [safety, drivability etc.]. In addition to these performance parameters, tyres have significant influence on the overall styling of the vehicle. It complements the primary theme of the vehicle. A right blend of engineering and art is essential for a successful tyre design. One cannot substitute the other. Amongst different steps of tyre design like, dimension finalization, tread design & martial design etc. the most critical step is tread design (profile, pattern & compound)

Few areas designers are focusing today to  meet the near/middle future demands are

• Lowering the rolling resistance – without compromising grip
• Shortening the time to market.
• virtual simulation of tyre performance

 

References

1.  ‘’The pneumonic tyre’’, National Highway Traffic Safety Administration, Feb 2006
2. T. French, Tyre Technology, Hilger, New York, 1989.
3. Mechanics of Pneumatic Tires, S. K Clark, ed., University of Michigan, US Department of Transportation, National Highway Traffic Safety Administration, Washington, DC, 20590, 1891.

     4.  Handbook of vehicle-road interaction: vehicle dynamics, suspension design, and road damage / edited by David Cebon. p. cm. - (Advances in engineering), ISBN 9026515545

    5. “Tyre and Vehicle Dynamics” , Hans B. Pacejka,  Professor Emeritus Delft University of Technology, Consultant TNO Automotive Helmond

     The author is General Manager - Product Development,2&3-Wheeler tyres, CEAT Tyres

NASA has launched a three-phase competition offering USD 155,000 in prizes to develop next-generation wheels for lunar rovers, as the US space agency prepares for sustained exploration missions to the Moon’s surface.

The “Rock and Roll with NASA Challenge” seeks lightweight, durable wheel designs capable of traversing the Moon’s harsh terrain of razor-sharp regolith whilst maintaining performance in extreme temperature variations and carrying substantial cargo loads at higher speeds.

The competition addresses critical mobility challenges facing future lunar missions, where traditional rover wheels have struggled with the Moon’s abrasive surface materials and temperature extremes that can plummet to minus 173 degrees Celsius during lunar nights.

“The next era of lunar exploration demands a new kind of wheel – one that can sprint across razor-sharp regolith, shrug off extremely cold nights, and keep a rover rolling day after lunar day,” NASA stated in announcing the challenge.

The programme unfolds across three distinct phases. Phase 1, which opened on 28 August and runs until 4 November 2025, will reward the best conceptual designs and analyses. Phase 2, scheduled for January through April 2026, will fund prototype development. The final phase in May-June 2026 will test leading designs through live obstacle courses simulating lunar conditions.

For the concluding phase, NASA will deploy MicroChariot, a 45-kilogram test rover, to evaluate top-performing wheel designs at the Johnson Space Centre Rockyard facility in Houston, Texas. The testing ground will simulate the challenging lunar terrain that future missions must navigate.

The competition remains open to diverse participants, from university student teams and independent inventors to established aerospace companies, reflecting NASA’s broader strategy of engaging private sector innovation for space exploration technologies.

NASA mobility engineers will provide ongoing feedback throughout the competition phases, offering participants insights from the agency’s extensive experience in planetary rover operations, including successful missions to Mars.

The challenge comes as NASA intensifies preparations for the Artemis programme, which aims to establish a sustained human presence on the Moon and serve as a stepping stone for eventual Mars exploration missions.

Current lunar rover designs have faced limitations in speed, cargo capacity, and durability when operating across the Moon’s challenging surface conditions, creating demand for breakthrough mobility solutions that can support extended surface operations.

The competition timeline positions Phase 2 prototype funding to commence in January 2026, allowing successful Phase 1 participants several months to refine their concepts before advancing to hardware development.

VMI will display its automated Strainer Plate Cleaning Station, a significant innovation designed to address a longstanding challenge within the rubber manufacturing industry, at the upcoming Global Polymer Summit in Cleveland. This comes at a critical time of rapid economic expansion in the United States, largely fuelled by construction and industrial renewal, which is driving increased demand for high-quality, efficiently produced rubber components.

These components are essential across a vast spectrum of applications, from microscopic seals and industrial machinery to pipelines and specialised products for extreme environments. To keep pace, US manufacturers are actively seeking advanced equipment that combines superior quality, shorter lead times and robust stateside support. For over two decades, VMI has met these exact needs from its Ohio operations, offering German-engineered solutions supported by responsive local service.

The new Strainer Plate Cleaning Station exemplifies VMI's pioneering ‘Hands-off, Eyes-off’ automation philosophy, previously applied to its industry-standard tyre building machines. This system utilises advanced robotics to completely transform what has traditionally been one of the most labour-intensive, unpleasant and hazardous jobs in a rubber factory. The automated Strainer Plate Cleaning Station will be demonstrated in operation at VMI’s booth, number 1430, during the Global Polymer Summit from 8th to 11th September.

The benefits of this automation are substantial. Companies can reallocate skilled workers to more value-added production roles, thereby boosting overall productivity and driving down unit costs. This enhanced efficiency allows businesses to become more competitive and responsive to dynamic market demands. The system integrates seamlessly with VMI’s extrusion and gear pump systems, which are backed by proprietary management software that enables the flexible production of both standard and highly specialised components on a single platform.

The Qingdao Municipal Government Information Office recently hosted a media briefing on ‘Shandong's Top Brands on the Industrial Chain – Intelligent Equipment Industrial Chain’ at the MESNAC Jiaozhou Equipment Industrial Park. Senior leaders from MESNAC and three other prominent firms were in attendance to present their advancements and field questions from journalists.

A central focus was on MESNAC's proprietary ROC R&D platform, a unique modular system engineered specifically for the rubber equipment sector. This platform is fundamentally structured around client requirements, integrating comprehensive product design, technological development and rigorous testing protocols. This architecture facilitates a configurable development process, allowing for both large-scale customisation and remarkably agile product delivery. The company's operational philosophy was explained as a dedicated team model, where a single unit focuses its expertise on one product for its entire lifecycle. This meticulous approach has generated significant industry innovations in recent years, including fully automatic material weighing systems, unmanned tire building machinery and intelligent tyre curing press workshops capable of operating as fully unmanned ‘lights-out’ facilities.

The event included a practical demonstration of this technology in action. Attendees witnessed the NPS Semi-steel One-stage Building Machine, which achieves a single-tyre production cycle of just 35 seconds through complete automation. This system boasts world-class efficiency, requiring only one person to supervise multiple machines simultaneously. It embodies a new generation of intelligent manufacturing by seamlessly integrating cutting-edge technologies such as precision machine vision, industrial robotics, sophisticated industrial IoT software and autonomous learning capabilities.

NEXEN TIRE has inaugurated a cutting-edge High Dynamic Driving Simulator at its Magok-based NEXEN UniverCity R&D centre in Seoul. A first-of-its-kind installation within the South Korean tyre industry, this advanced system represents a pivotal step in modernising tyre development by leveraging virtual reality and artificial intelligence.

The simulator functions by creating a highly realistic virtual driving environment. Engineers can input specific vehicle data and parameters to conduct precise testing of performance metrics such as acceleration, braking and handling across a diverse range of simulated road conditions, all within a controlled laboratory setting.

This technological advancement is expected to significantly streamline NEXEN TIRE’s research and development operations. It will reduce the need for physical prototypes and extensive real-world vehicle tests, which in turn accelerates development cycles and lowers associated costs. A major strategic benefit is the enhanced ability to meet the exacting performance standards required by global automakers for original equipment tyres, especially for new and high-performance vehicle models.

The shift towards virtual testing also supports the company's sustainability objectives by diminishing the fossil fuel consumption typically involved in traditional road testing, thereby supporting its broader environmental, social and governance (ESG) commitments. This move aligns with a larger industry trend where automakers are rapidly adopting virtual processes to improve efficiency.

Looking forward, NEXEN TIRE plans to build upon this simulator to establish a comprehensive Full Virtual Development Process. This long-term strategy aims to integrate advanced simulation with finite element method analysis and AI, ultimately working towards a future where physical testing is largely replaced by virtual validation.

John Bosco (Hyeon Suk) Kim, CEO, NEXEN TIRE, said, “Ahead of the industry trend towards virtual development of vehicles and tyres, the establishment of our High Dynamic Driving Simulator is a strategic investment to lead the future mobility sector. By combining VR and AI technologies, we will enhance both the efficiency and precision of our R&D while contributing to ESG management, thereby strengthening our global competitiveness.”