Nowadays a disc brake is one of important auto parts for motorbike cycle industry which effected directly to life safety. As the result this project aims to test the performance of the disc brake in order to study the physical disc brake that effects to braking distance and to be an alternative for testing the brake disc. Therefore the braking performance tester was designed and created in the single dynamometer which was not over 9.70•kgm2 as the moments of inertia of motorcycles. Regarding JASO T204:2001 this test was focused on the 3 different types of brake discs (i.e. normal type grooving type and perforated type). The tested temperature was at normal state of the brake disc temperature (60°C - 80 °C) and at high state (more than 100 °C). The braking force from 9.81N to 34.33N at master cylinder was tested. The result revealed that at normal temperature the braking performance of the three disc brakes (normal type grooving type and perforated type) was at 7.29 9.10 และ 9.50 m/sec2 per 1m2 of contact surface areas respectively. However the brake performance at high temperature was at 7.21 9.03 และ 9.46 m/sec2 per 1m2 of contact surface areas respectively. This result reveals that the most efficient disc brake at normal temperature was perforated type of disc brake which was 30.32% different from normal type of disc brake. Likewise; the perforated type of disc brake was the most performance disc brake at high temperature which was different from normal type of disc brake at 31.21%

The purposes of this study were to investigate the heat transfer and the vibration characteristics caused by front and back vented brake disc which had physically different shapes affecting braking distance. In accordance with the theory of heat transfer the heat transfer rates of two types of brake disc were different and played an important role in the deformation during usage. The single dynamometer was conducted to the experimental work as an engineering tool with boundary conditions according to JASO C406 standard. One degree of freedom (DOF) acceleration signals on the brake caliper were analyzed. The results obviously discovered that the back vented brake disc was able to reduce the vibration up to 43.5% comparing to the front vented brake disc in case of the braking temperature 200C initial breaking speed 50 km/h and the hydraulic pressure of 4 MPa. Besides the hydraulic pressure at 4 MPa generated the maximum vibration. Furthermore the initial braking speed and the braking temperature were also the important factors. Regarding braking distance results the results of the experimental work obviously discovered that the back vented brake disc created braking distance shorter than front vented brake disc. Besides there were important factors as braking temperature hydraulic pressure and initial speed of braking. Especially the high braking temperature caused an increase of deceleration and a decrease of braking distance. Moreover the high hydraulic pressure produced a deduction of braking distance and an increase of deceleration. Finally the initial speed of braking directly varied to the braking distance

Admittedly a disc brake plays an important role in the auto part industry since it concerns directly with safety. Therefore the wide range of disc brake has been designed in order to develop its heat ventilation. There are two physical kinds of brakes: front-vented disc brake and backvented disc brake. As a result such difference affects directly to the heat ventilation which is a vital factor of the brake’s capability. The project team recognizes its importance and tries to create the test to find out the temperature diffusion of the disc brake with the hope to evaluate the coefficient of the heat convection varied by the temperature changing in both kinds of brakes under the forced heat convection in the steady condition. However the steady heat conduction and radiation value will not be counted because it is insignificant. The JASO C406: 2000 Standard is adopted as a guideline in the test. The outcome coefficient of heat conduction will be used in the simulation via the Finite Element Method (FEM) in order to study the temperature diffusion and heat ventilation of both kinds of brakes at each temperature level. Consequently the experimental work reveals then the heat convection coefficients of both kinds are unidirectional. The heat convection coefficient of the front-vented disc brake is 4.40 % in average higher than that of the back-vented disc brake. From the simulation the front-vented disc brake can ventilate the heat better than the back-vented disc brake at 3.02 % in average. It can be summarized that the front-vented disc brake has more temperature difference than the backvented disc brake. Hence the front-vented disc brake likely gets more stress from the temperature than the back-vented disc brake and might be damaged during the operation more than the another type.

A disc brake is one of important auto parts for motorbike cycle industry which effected directly to life safety. As the result this project aims to test the performance of the disc brake in order to study the physical disc brake that effects to braking distance and to be an alternative for testing the brake disc. The braking performance tester was designed and created in the single dynamometer which was not over 10 Hp and the 17of inertia .70 kg. m. Referring to testing state of JASO T204:2001 standard this tester focused on testing the 3 different types of disc brake i.e. normal type grooving type and perforated type. The tested temperature was at normal state of the brake disc temperature (60° C - 80° C) and at high state (more than 100° C). The braking force from 9.81 N to 34.33 N at master cylinder was tested. moments was not over 92 The result revealed that at normal temperature the braking performance of the three disc brakes (normal type grooving type and perforated type) was at 17.76 21.80 and 19.00 per 1 mrespectively. However the brake performance at high temperature was at 14.41 18.06 and 18.93 per 1 m. This meant that the most efficient disc brake at normal temperature was grooving type of disc brake which was 22.74% different from normal type of disc brake. Nevertheless; the perforated type of disc brake was the most performance disc brake at high temperature which was different from normal type of disc brake at 25.32% 2 of contact surface areas 2 of contact surface areas respectively2m/s2m/s

Nowadays the automotive parts industry greatly grows up in Thailand. Brake disc is one of products that play a role in safety area. As a result the various designs such as front and back-vented brake discs are occurred to improve the performance of usability. Consequently this study aims to develop the ability of braking dynamometer from 9.7 kg-m.1 kg-m. Moreover the influence of the front and the back-vented brake disc effecting on braking distance was investigated by single dynamometer referenced JASO C406 for testing condition. Therefore both of discs were operated under 100 200 and 300 °C of braking temperature and 2 4 and 6 MPa of line hydraulic pressure of braking. 2 to 1272 of moment of inertial From experimental works the test results reflected that the back-vented brake disc created braking distance shorter than front-vented brake disc ostensibly. Besides there are also diversity of factors as temperature pressure and initial speed of braking. Especially the higher temperature caused an increase of deceleration and a decrease of braking distance. Moreover the higher pressure produced a deduction of braking distance and a rise of deceleration. Finally the initial speed of braking was directly various the braking distances in same condition.