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Fatigue due to motorcycle riding is an important field of study as it is one of the key parameters through which the end user rates the motorcycle. The fatigue due to riding can be broadly divided into two major activities the body performs: 1. Maintain the body posture, absorbing road shocks and 2. Generate the required forces to control the motorcycle. The current methods of estimating fatigue are limited to subjective feel and objective measurements of parameters like steering torque; shock levels at seat, etc. during riding. These parameters estimate the inputs to the vehicle irrespective of the rider posture and hence predict same fatigue for all postures, but it is well known that the riding posture significantly affects the fatigue of rider. In this study the authors propose a direct way of measuring fatigue using Electromyography (EMG). The objective of this study is to determine physical fatigue due to motorcycle riding using surface EMG.

Typically the velocity dependent hydraulic damper characterization is done using a sinusoidal input to the damper. Damping force vs. displacement and velocity plots are used to represent the damping behaviour. It was observed that the dampers exhibit equal damping characteristics using this conventional method, shows a significant difference in ride comfort levels of the vehicle. This behaviour primarily arises due to the variation in response of the damper with the excitation frequency. On actual riding conditions, apart from harmonic loads, the suspension experiences impact loads that affect the damping generation characteristics. So the damper also needs to be characterized with variation of frequency ranging from 0.5 Hz to 25 Hz. Due to the limitations of damper stroke and input frequency, complete characterization of damper is not possible with sinusoidal input test rig.

Dynamic behavior of motorcycle is influenced by several parameters, which derive from various subsystems that go into making a motorcycle assembly and the way they are integrated. Structural stiffness has been a key consideration by most of the dynamics engineers, in design and tuning of motorcycle dynamics. Different approaches have been used in the study of structural stiffness effect, like lumped mass model, distributed stiffness model, static stiffness and dynamic stiffness. A limited research has been done on the effect of carrier luggage supported at rear end of the frame on steering oscillations. The authors of this paper found that the effect of significant changes in the parametric values of seat structure stiffness is not captured vividly in typical mathematical models available so far, whereas the experimental bikes built with such changes demonstrate substantial change in the dynamic behavior, quantified by both expert rider’s feel as well as objective measurements.

In developing countries roads have a mix of high undulations as well as smooth and flat surfaces on highways. And also two wheelers are used for commuting with one or two people rather than for sport. A variety of spring characteristics are required to maintain the ride height for solo and doubles and wide variety of damping characteristics are required for various road conditions, loading conditions and speeds to achieve desired ride and handling characteristics. The spring and damper characteristics that are desired for good ride comfort will results in poor handling at high speeds. Achieving a very good level of ride comfort on rough and smooth terrains combined with an equally good level of handling with various loading conditions in the speed range of 20 to 120 Kmph is a highly challenging task. So most of the two wheelers are tuned for one loading case (solo or doubles) and either for ride comfort or handling with compromise on the other.

In low speed bikes drum brakes are used on large scale. In drum brake system, brake shoes are relatively more enclosed by neighboring parts compared to disc brakes. Hence, drum brake cooling is not efficient like disc brake. This results in higher steady state temperature, which may lead to brake noise, brake fading, glazing etc. in drum brakes. Further, the high temperature plays a key role for design of labyrinths too. Hence, designing of the drum brakes for extreme heating is critical. This paper elucidates the thermo-mechanical behavior in two-wheeler drum brakes under extreme braking and their consequence manifesting itself in permanent distortions resulting in the brake failure. Experiments as well numerical simulations are carried out to investigate the thermo-mechanical behavior of drum brakes. Experiments are conducted at extreme braking for maximum thermal loading on the drum brake. The rise in temperature of the drum is measured with sensor.

Tyres are the primary contact between the vehicle and the road. It serves as the medium of communication between the road and the rider, which it does in terms of road loads and displacements. Therefore, measurement of dynamic wheel forces experienced by a two-wheeler is crucial for tuning the ride and handling characteristics of the vehicle. Currently, there are standard wheel force transducers available in the market, which are extensively used in cars. However, mass of such a system is relatively high to be used on two-wheelers. Special wheels and adaptors increase the unsprung mass considerably, which changes the dynamics of the vehicle. Moreover, cost of such systems is exorbitantly high to be used for two-wheelers. This paper describes the development of an innovative and a highly versatile and low-cost alternative method for real-time measurement of dynamic wheel loads and moments of a two-wheeler when compared with the currently available systems in the market.

Motorcycle segment is growing very fast in India. The average riding speeds are much less owing to the road conditions and traffic. The roads have a mix of both high undulations as well as smooth and flat surfaces on highways. Achieving a very good level of ride comfort on such rough & smooth terrains combined with an equally good level of handling in the speed range of 20 to 80 Kmph is a highly challenging task. Monoshock rear suspension is one of the options engineers can look at, to enhance the handling behavior of motorcycles without compromising on the ride comfort too much. Our work is aimed at building a generic analytical model of typical mono shock motorcycle rear suspension that will enhance the understanding of system kinematics and extending its application for optimizing the design towards a better performance of the complete motorcycle. Both direct mount and linkage mount monoshock suspensions are studied.