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

Hana Technologies, Inc. (Hana RFID), a global leader in the design and manufacturing of embeddable RFID tyre tags, has become the first RFID company to join the Circular Rubber Platform. This development aligns with Hana RFID’s mission to drive innovation in tyre traceability and reinforces the company’s long-standing commitment to sustainability and circularity in the tyre and rubber industry.

Hana RFID has been at the forefront of RFID-enabled tyre traceability since 2005, facilitating smooth tracking from cradle to grave and promoting circularity. Hana's RFID tyre tags, which are embedded during manufacturing, provide each tyre a distinct digital identity, facilitating complete lifetime tracking from manufacture and use to recycling and reuse. Hana hopes to promote RFID usage in sustainable tyre lifecycle management by working with leading companies in the sector, which will eventually save waste and increase resource efficiency.

Using radio frequency identification (RFID) technology, an RFID tyre tag is a tiny, embedded device that tracks, monitors and controls tyres. In addition to providing smooth connection with inventory monitoring, fleet management systems and other digital applications, such as the European Digital Product Passport (DPP), these tags produce digital twins of tyres. Hana's RFID solutions empower the whole tyre ecosystem to expedite fleet management, improve inventory control, optimize maintenance, and create creative business models that increase sustainability and efficiency.

Val Peters, VP – Marketing, Hana RFID, said, “We are excited to join the Circular Rubber Platform as the first RFID company in this initiative. RFID technology is essential for advancing a circular economy in tyre manufacturing, and we look forward to collaborating with partners across the rubber sector to drive sustainability on a broader scale.”

Enrico Koggel, Co-Founder, Circular Rubber Platform, said, “RFID technology is key to enabling a circular rubber economy. RFID enables seamless tracking from production to end-of-life recycling by connecting material and production data into each rubber product. It provides traceability and easy identification and allows for smart sorting of materials and efficient recycling to ensure responsible reuse, remanufacturing, recycling and waste reduction. We are therefore very happy to announce Hana as a new member of the Circular Rubber Platform, with the technology and experience they can provide to the platform. We look forward to sharing knowledge on RFID and working out opportunities for this technology in rubber industries that require Digital Product Passports in the near future, such as footwear.”

TÜV SÜD has expanded its test laboratory in Frankfurt am Main and unveiled new testing facilities at an Open Lab Day at the site, giving customers and employees an exclusive insight into the new state-of-the-art testing environments. The expansion strengthens TÜV SÜD’s position as a leading provider of independent testing and certification services.

Car charging plugs can now be tested in the lab to assess features like weather resistance, mechanical strength and electrical safety. To guarantee the endurance and durability of charging plugs and other parts, the new lab can also conduct crash testing on them. The inclusion of performance testing for tiny batteries is another significant development. Basic functional analysis will be the main emphasis of these tests at first, but in the second part of the year, comprehensive safety and performance evaluations will be included. Similar to this, power tool testing capabilities have been greatly increased to give manufacturers an even more thorough evaluation of the calibre, robustness and safety of their goods.

The capability to ascertain the biogenic carbon content of materials is an additional highlight of the expansion. These assessments support the implementation of sustainable manufacturing methods by giving businesses evidence of the utilisation of renewable raw resources. In order to make sure that packaging and other materials fulfil the strictest safety regulations and don't leak dangerous compounds into food, the testing infrastructure for materials that come into contact with food has been increased at the same time. It's also important to note the recently added ability to evaluate welding fume filtration systems, which may undergo a thorough performance assessment and will soon be certified.

TÜV SÜD is now able to provide an even greater variety of chemical testing services to make sure that products satisfy the most recent regulatory standards thanks to the expansion of its Frankfurt laboratory. With standardised testing for compounds including PFOS, PFOA, C9-C14 PFCAs, and PFHxS, there is a special emphasis on PFAS analysis. Due to the laboratory's expansion, even more businesses may now make use of its extensive testing knowledge, which includes services related to durability testing, risk assessment and certification for a range of product categories.

Walter Reithmaier, CEO, TÜV SÜD Product Service GmbH, said, “By expanding our laboratory in Frankfurt, we are responding to growing demand for product testing and certification. Our new testing capacities will set new standards in safety, sustainability and performance. We look forward to supporting our customers with state-of-the-art testing technology and professional expertise.”

Chicago-based Koala Technologies (KTL), a leading automotive testing, measurement and evaluation tools provider, has launched Te.Sense Bloom – a breakthrough in non-destructive rapid tyre deflation testing. The company has introduced the base kits starting at USD 20,000.

The solution the company claims is fully compliant with FMVSS 110 and emerging EV stability test standards. The Te.Sense Bloom allows passenger vehicle manufacturers and tyre makers to cost-effectively reuse solutions, thereby optimising test programmes while reducing waste.

Currently, the rapid tyre deflation tests often rely on a vehicle being driven over special roadway cleats at defined speeds. This method sees tyres destructively punctured and destroyed by the cleats, and internal inflation pressure is quickly reduced to atmospheric pressure. At times, these tests aim to ensure that the tyres are safely seated on the wheels post rapid deflation, wile at times it is to evaluate vehicle stability in terms of tyre failure.

The company stated that this tests however require destroying multiple tyres, not only leading to waste but may also corrupt certain vehicle dynamics tests that call for a single, targeted tyre failure.

On the other hand, with Te.Sense Bloom, the industry can use non-destructive controlled, rapid deflation for the selected tyres. Using a controllable central air ejector valve with a volume and a flow capacity that simulates a sudden tyre press loss. While the method sounds simple and frugal, the innovation lies in relation with the turn-key nature of Te.Sense Bloom. Automotive testers and engineers get a repeatable set up method, easy in-car operation and simple connectivity with data acquisition systems. As part of its comprehensive supply to Te.Sense Bloom customers, KTL even offers a wheel setup service to simplify test preparations.

The other advantage of Te.Sense Bloom is that the tyre deflation event can be triggered from inside the vehicle or remotely that further expands test scenario possibilities. It can be used for testing tyre inflation pressures up to 100 PSI and speeds up to 140 kmph (87 mph). The real-time tyre inflation data at 100 Hz has a claimed data accuracy of +/-0.1 PSI.  

Kenneth Martin, Head of Tyre Testing at the Transportation Research Center, said, “We have significant experience with rapid tyre deflation tests, using all types of methods, and we’re looking forward to evaluating KTL’s Te.Sense Bloom, since it represents a turn-key, non-destructive solution. There’s definitely some baseline justification for test equipment like this because it fundamentally means consuming fewer tyres. But Te.Sense Bloom’s inherent connectivity opens some other doors also, since triggered and monitored rapid tyre deflations are becoming an area of interest for vehicle stability testing, especially in EV space.” 

The first U.S.-specification kit has been delivered to the Transportation Research Center in Ohio for initial evaluations.

Being compliant with EV stability testing standards the Te.Sense Bloom is already being used by OEMs globally such as Huawei AITO, SAIC Motor Corp and GAC Motor to conduct regulatory tests such as GB/T 38796-2020 (Performance Requirements and Test Methods of Automobile Blow-out Emergency Safety Device).

Mike Lee, Founder and President, KTL, added, “Koala Technologies is excited to introduce Te.Sense Bloom into new markets, beginning in 2025. Bloom has been widely adopted for vehicle development testing in China over the last several years, becoming a must-have tool for many OEMs and key suppliers. It’s one example, among many, of an excellent, trusted, useful automotive testing device that no one knows about outside China. A part of our mission at KTL is to shine a light on some of these exciting technologies that are currently available, but not widely known. Another part of our mission is to help customers achieve their goals more efficiently and at a lower cost. We look forward to the upcoming testing at the Transportation Research Center in Ohio, and we hope that Te.Sense Bloom proves to be a good fit for automotive development programmes in the U.S and beyond.”

Bridgestone Corporation has developed a new Tyre and Road Wear Particles (TRWP) vehicle collection method aimed at understanding the environmental impact of TRWP. The solution was also displayed at the Tire Technology Expo 2025, held in Hannover, Germany, from 4 to 6 March.

TRWP is made up of a blend of road pavement components and tread (tyre surface). In order to comprehend the particle size distribution, dispersion behaviour, and environmental impact – as well as to create effective collecting techniques – Bridgestone is actively engaged in a number of TRWP research projects. The company is dedicated to comprehending TRWP and lowering its generation through these initiatives.

Utilising the B-Mobility testing facility at the Bridgestone Innovation Park in Kodaira, Tokyo, the company has created a state-of-the-art technique that makes it possible to gather TRWP effectively. Bridgestone has used laser light scattering in conjunction with a high-speed camera to visualise the dispersion of particles like TRWP. Based on this, the company has developed a device that effectively catches TRWP and covers the whole tyre. Additionally, the technique made it possible to collect TRWP effectively in a state that removes the effects of exhaust pollutants and broken dust by employing autonomous driving and an electric car with regenerative braking.

Through the Tire Industry Project (TIP), which is part of the World Business Council for Sustainable Development (WBCSD), Bridgestone has been researching the physical and chemical properties of TRWP and their implications on the environment. In addition to the continuous co-creation and internal R&D cooperation, Bridgestone is speeding up its efforts to evaluate TRWP's environmental consequences by collecting it effectively and with a high recovery rate using its recently developed collection technology.