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In this study, alumina and graphite in a 98 % to 2 % ratio were prepared by mechanical milling for 80 hrs, then surface coated with 2 %Ag. The motorcycle wheel aluminum swarf was melted at 800 °C then the new hybrid (Al2O3-GNs)Ag in proportions of 1, 2, and 3 wt% was added at 600 rpm for 10 min. The microstructure of the rolled samples showed a good distribution of the hybrid (Al2O3-GNs)Ag and good adhesion with the aluminum matrix. The hardness increased by adding alumina and the hybrid up to 3 %. The as-rolled 3 %(Al2O3-GNs)Ag samples gave the best mechanical properties (yield strength, tensile strength, and elongation) compared to the as-cast aluminum reinforced with alumina and hybrid. The corrosion rate was improved by reinforcing the aluminum with the hybrid (Al2O3-GNs)Ag. Due to reducing the particles size and increasing the surface area after the rolling process, a deterioration in the corrosion resistance was observed. [ABSTRACT FROM AUTHOR]

Motorcycle designers aim to enhance vehicle performance, stability, and safety, especially when the vehicle is approaching the tyres' friction limit. A strategy to achieve these purposes is to design All-Wheel Drive (AWD) vehicles with active torque distribution. Nowadays, effective technical solutions for powering the front wheel of a motorcycle have been proposed. The use of traction on both front and rear wheel is convenient when tyre friction is low, enhancing vehicle safety and performance. In this context, this paper presents a sensorless, open-loop traction strategy for AWD motorcycles that improves performance and stability both in straight running and in cornering, without requiring the knowledge of road-tyre adherence. This novel traction distribution strategy is based on the idea of maximising the area of the motorcycle performance envelope, also known as g-g diagram. A simplified mathematical model is used to find closed-form solution to this problem, then converted into a control algorithm for the front and rear driving torques. The performance of the proposed method is assessed with simulations: a detailed model of a light electric motorcycle is used for calculating the non-linear vehicle performance envelope, the acceleration response in straight running and cornering, and the response to road irregularities. Moreover, a comparison with feedback slip-based traction control system is conducted. Simulation results indicate that the AWD motorcycle outperforms the conventional rear wheel drive motorbike almost in all situations, especially when road-tyre adherence is low, and that no counter-indication for the adoption of the AWD architecture exists. [ABSTRACT FROM AUTHOR]

The front wheel of a motorcycle during heavy braking in straight motion can lock before reaching the maximum longitudinal ground force, a problem affecting especially performances of road racing motorcycles. This is preceded by a self-excited vibration, referred to as front wheel patter, in the frequency range between 7 and 10 Hz. Aim of the present study is the identification of the actual switching mechanism to instability together with its governing parameters. A minimal model of the front assembly of a motorcycle is proposed, and its stability in equilibrium configurations is studied via eigenvalue analysis. The sensitivity with respect to all its governing parameters is analysed by means of stability maps and the self-excitation mechanism is explained with the aid of energy balance analysis and phase-diagrams. The results are compared to those existing in the literature and to numerical simulations obtained from a full motorcycle multibody model. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the effects of the rotation speed of casting and T6 heat treatment on the fatigue crack growth rate of a motorcycle wheel manufactured using centrifugal casting. The density, porosity, tensile properties, and microstructure were examined in the evaluation of the fatigue crack growth rate of the aluminum scrap. The results showed that applying increased rotation speed is effective in increasing the alloy's tensile stress and material density, as well in reducing porosity and fatigue propagation rate. T6 heat treatment also increases the aluminum's tensile properties and reduces the fatigue crack growth rate. Recycled aluminum alloys can be improved by increasing the rotation speed of centrifugal casting and following it with T6 heat treatment in the production of a cast motorcycle wheel. [ABSTRACT FROM AUTHOR]

• A visual detection method is proposed to rapidly detect the cracks of the composite metals. • The effectiveness of the proposed method was verified by testing the motorcycle wheel hubs. • The results demonstrate the reliability of the proposed method. Many kinds of products are cast from two or more metals to take advantage of the properties of different metals. Due to different thermal properties, an air gap may occur between the interfaces of two metals, which seriously affects the product quality. It is difficult to detect this kind of cracks with conventional metallographic detection methods and the detection efficiency is low. Based on this, a visual detection method based on two-channel feature fusion is proposed to rapidly detect the cracks, using flowable color ink to paint on the end face of the composite metals. If the flowable ink flows into the gap of the metal interfaces, a crack will occur in ink, reflecting the internal defects at the junction of the metals. The effectiveness of the proposed method was verified by testing the motorcycle wheel hubs which are casted with two metals. The wheel hub painted with ink was applied with an alternating load to enlarge the gap. Two images of the ink were captured with a camera before and after the alternating load was applied. Both images were converted from RGB model to HSV model, and both S and V channels of the two images were processed with the dual-channel feature fusion algorithm. A variety of experiments were conducted to determine a set of optimized parameters of the algorithm, and 1000 groups with qualified and defective hub images were tested. The results demonstrate the reliability of the proposed method, which can complete the detection of a product within 10 s, and the crack recognition rate can reach a high value of 97 %. [ABSTRACT FROM AUTHOR]

Safety features like antilock braking systems (ABSs) have become an essential feature of road vehicles now a days. ABSs are designed for the purpose of maintaining the wheel slip in the required value during sudden braking to ensure the vehicle steerablility and non-skidding. Uncertain factors such as type of road surface, tyre pressure, vehicle mass, etc., cause the required wheel slip to be continuously changing. Hence, controlling the wheel slip remains a difficult task always. This situation leads to a need for design of a controller, which will be capable of dealing with these uncertainties. One of the controllers which can effectively deal with the parametric and modeling uncertainties is sliding mode controller (SMC). Fuzzy logic is a knowledge based system which is very much useful in handling the systems whose models are not developed fully or accurately or information about the system is uncertain. In this paper, a robust and adaptive Fuzzy sliding mode controller (FSMC) is proposed for a laboratory ABS model by combining fuzzy logic with sliding mode controller. The performance of the proposed FSMC is assessed through digital simulations for various initial conditions of vehicle velocity and road surface conditions. [ABSTRACT FROM AUTHOR]

For the lightweight design of the wheel rim of motorcycles, the knowledge of the way in which contact forces are transmitted by the tire is of crucial importance. In this paper, an analytical model of the tire is developed and explicit formulae giving the distribution of the radial and axial forces acting on the wheel rim for a given vertical load are derived. The analytical model is validated by means of a finite element method (FEM) model and experimental tests. The proposed analytical model is able to predict the radial deflection of both a front and a rear tire for a racing motorbike with very good accuracy over a wide range of inflating pressures and vertical loads. The force distributions are in very good agreement with the results of the FEM model. Experimental tests show that the force distribution at the interface between the tire and rim can be used to predict the stress distribution in the rim with a good accuracy. [ABSTRACT FROM AUTHOR]

India, and its cities and towns are experiencing an unprecedented and unparalleled motorization in recent times. The motorization pattern in India indicates that nearly three fourths of the total registered vehicles are motorized two wheelers. Even though a significant increase is seen in urban areas, there is a noticeable increase in rural areas also. Road deaths and injuries are increasing at a rapid pace in Bengaluru and other parts of India and are likely to increase if systematic and scientific road safety policies and programmes do not accompany this change. Helmets form an important protective gear in protecting the head among two wheeler riders/pillion riders in fatal road traffic injuries. The present study was performed to study the effectiveness of Helmet as a protective gear in preventing fatal Head Injury among Two Wheeler Riders/Pillion Riders in Road Traffic Injuries. In this study, we studied the usage of Helmet among Two Wheeler Rider/Pillion Riders, type of Helmet they wore during the fatal day, Head Injury pattern in them among others to find out the effectiveness of Helmet. A total number of 220 cases were included in the study for a period of 3 years. Statistically significant observations were made in the study which proved that a standard ISI standard full face Helmet is very effective in reducing the fatal Head Injury in two wheeler accidents. [ABSTRACT FROM AUTHOR]