1、_ 6$(7HFKQLFDO6WDQGDUGV%RDUG5XOHVSURYLGHWKDW7KLVUHSRUWLVSXEOLVKHGE6$(WRDGYDQFHWKHVWDWHRIWHFKQLFDO and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising tKHUHIURPLVWKHVROHUHVSRQVL
2、ELOLWRIWKHXVHU SAE reviews each technical report at least every five years at which time it may be revised, reaffirmed, stabilized, or cancelled. SAE invites your written comments and suggestions. Copyright 2013 SAE International All rights reserved. No part of this publication may be reproduced, st
3、ored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE. TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada) Tel: +1 724-776-4970 (outside USA) Fax: 724-776-079
4、0 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.org SAE values your input. To provide feedback on this Technical Report, please visit http:/www.sae.org/technical/standards/J108_201312 SURFACE VEHICLE RECOMMENDED PRACTICE J108 DEC2013 Issued 1969-07 Stabilized 2013-12 Superseding J108
5、NOV2007 Brake System Road Test Code Motorcycles RATIONALE The Technical Report covers brake test procedures which, for foundation brake systems, are mature and not likely to change in the foreseeable future. Additional test procedures for advanced braking systems including ABS are addressed elsewher
6、e. STABILIZED NOTICE This document has been declared “Stabilized“ by the SAE Motorcycle Technical Steering Committee and will no longer be subjected to periodic reviews for currency. Users are responsible for verifying references and continued suitability of technical requirements. Newer technology
7、may exist. Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-1. ScopeThis SAE Recommended Practice establishes a uniform procedure for the level road test of the brakesystems of all classes of motorcyc
8、les intended for highway use.1.1 PurposeThe purpose of the recommended practice is to establish brake system capabilities with regard to:1. Deceleration or stopping distance versus input, as affected by vehicle speed, brake temperature, andusage2. Lining characteristics3. Drum characteristics2. Refe
9、rencesThere are no referenced publications specified herein.3. Section A - InstrumentationLine pressure of pedal and lever force gaugesDecelerometerDirect reading temperature instrumentSpeedometer (calibrated)Odometer (calibrated)Thermometer - ambient (or ambient sensitive thermocouple)Optional Inst
10、rumentationPedal travel gaugeStopmeter (“fifth wheel,” distance only or shot marker)Solenoid stop counterStopwatch_SAE INTERNATIONAL J108 Stabilized DEC2013 Page 1 of 7Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without lice
11、nse from IHS-,-,-4. Section B - Installation Details1. Friction Material PreparationAttach and finish friction material per manufacturers specifications.2. ThermocouplesInstall the desired type of thermocouples in each brake. Any one of the followinginstallations may be used:a. Plug type. See Figure
12、 1.FIGURE 1TYPICAL PLUG TYPE THERMOCOUPLE INSTALLATIONb. Web-rim junction type, welded or otherwise, in intimate contact with the brake shoe near the web-rim junction.c. Thermocouple inserted in a hole drilled from the lining edge, approximately one-half the width ofthe lining in depth and as close
13、to the shoe rim as possible.All thermocouples are to be located in the approximate center of the most heavily loaded shoe,one per brake (two per brake on double-leading shoe brake).3. Brake Drum or RotorSurface finish and dimensional characteristics (with special emphasis on runoutof rubbing surface
14、) of brake drums or rotor shall be in accordance with manufacturers specificationsfor each test._SAE INTERNATIONAL J108 Stabilized DEC2013 Page 2 of 7Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-4
15、. Brake AssemblyBrakes shall be prepared in accordance with manufacturers specifications withspecial attention to required load characteristics on all brake springs. Adjust brakes to manufacturersspecifications.5. Vehicle Test WeightVehicle test weight (W) in pounds shall be determined by the follow
16、ing formulafor all tests:(Eq. 1)For the Effectiveness Test, the test weight for two-wheeled machines designed to carry more than oneperson may be determined by the following formula:(Eq. 2)where:C = curb weight which is the weight in pounds of the vehicle with standard equipment, includingmaximum ca
17、pacity of fuel and oilS = vehicles designed seating capacityP = manufacturers specified payload for three-wheeled motorcycle only6. Test Conditionsa. Test CourseEffectiveness, fade and recovery test stops shall be conducted on a substantiallylevel (not to exceed 1% grade), dry, smooth, hard-surfaced
18、 roadway of Portland cement concrete(or other surface with equivalent coefficient of surface friction) that is free from loose materials.Also, guides to indicate 12 ft wide roadway lane shall be provided on the test course.b. Ambient Air TemperatureAmbient air temperature at fade and recovery tests
19、shall be between40 and 90 F.c. Applied Point and Direction of Lever Force and Pedal ForceAs shown in Figure 2, the point ofapplication of the lever force shall be one 1.2 in from the end of the brake lever grip and thedirection of the force shall be perpendicular, on the plane along which the brake
20、lever rotates, tothe handle grip. The point of application of the pedal force shall be the center of the foot contactpad of the brake pedal and the direction of the force shall be perpendicular, on the plane alongwhich the brake pedal rotates, to the foot contact pad.d. Test SpeedVehicles shall be t
21、ested at the specified speed for each test. Those vehicles whichcannot obtain the specified speed shall be driven at not less than 4 mph nor more than 8 mphbelow the practical maximum speed with the second number in the speed figure being either 5 or0. (For example: If 69 mph is the maximum speed, t
22、he test speed for the 70 mph requirementwould be 65 mph.) FIGURE 2WC150SP+=WC20 lb+=_SAE INTERNATIONAL J108 Stabilized DEC2013 Page 3 of 7Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-7. Test Proce
23、durea. During all phases of this procedure, any unusual performance such as grab, noise characteristics,or wheel skid are to be noted and recorded. Note any uncontrollable braking action causing thevehicle to lose stability, to overturn, or to swerve out of a 12 ft wide roadway lane.b. If brakes req
24、uire warming to prescribed temperature, use the burnish procedure and shorteninterval if necessary.c. All stops shall be made with the clutch disengaged, or in neutral.d. Brake input on the tests other than preburnish check and effectiveness test shall conform to theprescribed value and be held cons
25、tant during the brake operation.e. When a recording decelerometer is used, deceleration shall be determined by the average of fourmeasurements, which are made at the four points dividing the braking time into five equal portions.f. When stopping distance is used, deceleration may be determined by th
26、e following formula:(Eq. 3)where:V = velocity, mphS = stopping distance, ftg. Initial brake temperature is defined as that of the highest reading thermocouple taken 0.1 milebefore stop with the brakes released.5. Section C - Test ProcedureThe test procedure shall conform to the following:1. Preburni
27、sh Checka. Brake Operational CheckIn order to allow for a general check of brakes, instrumentation, andvehicle operation, the following steps are to be run:Conditions:Stops Required10Stop Interval0.5 mileInitial Speed30 mphCooling Speed30 mphBrake InputEstablish brake input to give a deceleration of
28、 10 fpspsb. Establishing Brake Input ProportioningAssuming the above-mentioned test is performedsatisfactorily, establish brake input proportioning to be used in the succeeding tests, excepteffectiveness tests, according to the following procedures. (If one pedal or lever operates allbrakes, this st
29、ep may be omitted.)1. Conduct stopping tests at 50 mph (or maximum vehicle speed if 50 mph is not obtainable) witha brake temperature for each brake between 100 and 175 F before each stop.2. The stopping tests should be conducted with the rear brake alone and then the front brakealone. The lever or
30、pedal inputs shall be 5 lb for the first stop and increased at increments notexceeding 10 lb on succeeding stops until sufficient plotting data are obtained. Care shouldbe taken to avoid wheel skid. The average or steady deceleration or total stopping distanceshall be measured for each stop.3. This
31、information shall then be plotted as deceleration versus pedal and hand lever pressure.4. This plot shall then be used to determine the appropriate brake control input force to achieve a60/40 front to rear retardation proportioning.a1.075 V2S=_SAE INTERNATIONAL J108 Stabilized DEC2013 Page 4 of 7Cop
32、yright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-2. First Effectiveness TestConduct the test and record actual brake input and deceleration at eachinitial speed. Stay alert for any hazardous condition wh
33、ich may cause the vehicle to lose stability dueto wheel skid, to overturn, or to swerve out of the specified width roadway lane.a. Conditions for Simultaneous Braking with Both Front and Rear WheelsInitial Speed20, 30, 50, 70 mphInitial Brake Temperature (each stop)100 to 175 FBrake InputIncrease br
34、ake input for each initial speed until wheel skid occurs on the rear wheel.Take the front wheel as close to skid as possibleb. Individual Braking with One Wheel (omit if only one brake control operates all brakes)Repeatprevious test procedure using first the front wheel brake and then the rear wheel
35、 brake withconditions the same as in Section C, item 2(a).3. Burnish TestConduct the test under the following conditions and record deceleration versus brakeinput. After completion of the test, inspect brake system for any unusual condition. Check to makesure that approximately 80% or more lining co
36、ntact is obtained before proceeding with SecondEffectiveness Test. If the lining contact is not satisfactory, repeat Burnish Test. Readjust brakes.Stops Required200 (minimum)Initial Speed30 mphCooling SpeedSame as initial speedInitial Brake Temperature (each stop)150 F 10 FStop IntervalAs required t
37、o achieve 150 F 10 F initial brake temperature, or a maximum of 1 mile.The 1 mile maximum must be observed even though the initial temperature exceeds 150 F 10 F.In this case, record the initial brake temperature for the 25th, 50th, 100th, 150th, and 200th stop.Brake InputEstablish brake input to gi
38、ve a deceleration of 12 fpsps.4. Second Effectiveness TestRepeat Section C, item 2First Effectiveness Test.5. First Fade and Recovery Testa. Baseline Check StopsConduct the test under the following conditions, measure decelerationversus input, and record observations:Stops Required3Initial Speed50 m
39、phInitial Brake Temperature (each stop)100 to 175 FBrake InputEstablish brake input to give a deceleration of 15 fpspsb. Fade TestConduct the test under the following conditions and record deceleration versus brakeinput. Also, record the following:1. Temperatures of all brakes at the end of every st
40、op.2. Ambient air temperature at beginning of Fade Test.3. Total elapsed time from end of the first fade stop to end of last fade stop.Conditions:Stops Required10Stop Interval0.25 mileInitial Speed50 mphCooling SpeedSame as initial speedInitial Brake TemperatureFirst stop only, 150 F 10 FBrake Input
41、Establish brake input to give a deceleration of 15 fpsps for first stop. Usethese input forces on all 10 fade stopsAccelerate to cooling speed moderately._SAE INTERNATIONAL J108 Stabilized DEC2013 Page 5 of 7Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduct
42、ion or networking permitted without license from IHS-,-,-4. Drive the vehicle for 1 mile at cooling speed after last fade stop and then perform the RecoveryTest.c. Recovery TestConduct the test under the following conditions and record deceleration versusbrake input. Record, at the same time, observ
43、ations on the following items:1. Temperatures of all brakes at the end of each stop.2. Ambient air temperature at beginning of Recovery Test.3. Total elapsed time from end of the first recovery stop to end of last recovery stop.Conditions:Stops Required12 (minimum)Stop Interval0.5 mileInitial Speed,
44、 Cooling Speed, Brake InputSame as specified in Section C, item 5(b) - FadeTestAccelerate to cooling speed moderately6. First Effectiveness Spot CheckConduct the test under the following conditions and recorddeceleration versus brake input:Stops Required2Initial Speed50 mphInitial Brake Temperature
45、(each stop)100 to 175 F.Brake InputBrake input to be the same as in Section C, item 5(a) - Baseline Check Stops7. First ReburnishRepeat Section C, item 3Burnish Test, except:Stops Required35 (minimum)8. Second Fade and Recovery TestRepeat Section C, item 5First Fade and Recovery Test.9. Second Effec
46、tiveness Spot CheckRepeat Section C, item 6First Effectiveness Spot Check.10. Second ReburnishRepeat Section C, item 7 - First Reburnish.11. Final Effectiveness TestRepeat Section C, item 2 - First Effectiveness Test.12. Final InspectionAfter completion of tests 1 through 11, disassemble all brakes; inspect and record allpertinent observations.13. Water Recovery TestReassembl
