ISO INTERNATIONAL STANDARD 28981 First edition 2009-11-01 Mopeds Methods for setting the running resistance on a chassis dynamometer CyclomoteursMethodes pour fixer la résistance a I'avancement sur un banc dynamométrique Reference number ISO 28981:2009(E) @ ISO 2009 ISO28981:2009(E) PDF disclaimer This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In accepts no liability in this area. Adobe is a trademark of Adobe Systems Incorporated. Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below. COPYRIGHTPROTECTEDDOCUMENT @ ISO2009 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, isO's memberbody in the country of the requester. ISO copyright office Case postale 56. CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyright@iso.org Web www.iso.org Published in Switzerland ii @ ISO 2009 - All rights reserved ISO 28981:2009(E) Contents Page Foreword Introduction 1 Scope 2 Normative references. 3 Terms and definitions . 4 Symbols...... 5 Test moped, chassis dynamometer and instruments . 6 Required accuracy of measurements . 7 Road test .... 7.1 Requirement for road.. 7.2 Ambient conditions for the road test . 7.3 Reference speed. 7.4 Specifiedspeed 7.5 Coastdown starting speed... 7.6 Coastdown time measurement beginning speed and ending speed. 7.7 Preparation of test moped..... 7.8 Rider and riding position .. 7.9 Measurement of coastdown time.... 8 Data processing. 8.1 Calculation of running resistance force .8 8.2 Running resistance curve fitting .... 8.3 Target running resistance force for chassis dynamometer setting.. 9 Chassis dynamometer setting derived from on-road coastdown measurements 8 9.1 Requirements for the equipment .... 9.2 Inertia mass setting.... .9 9.3 Warming up of chassis dynamometer . 9 9.4 Adjustment of tyre pressures ... 9.5 .9 9.6 Procedures for setting chassis dynamometer .. 9.7 Verification of chassis dynamometer.... 12 10 Chassis dynamometer setting using the running resistance table 12 10.1 Applicability.. 12 10.2 Requirements for the equipment ..... 12 10.3 Setting the running resistance force on the chassis dynamometer. 14 10.4 The specified speed for the chassis dynamometer.... 14 10.5 Verification of chassis dynamometer... 14 AnnexA(normative)Mopeddescription. 16 AnnexB(normative)Chassisdynamometerandinstrumentsdescription. .18 Annex C (informative) Record of coastdown time and chassis dynamometer setting .. 20 Bibliography. 23 @Iso 2009 -All rights reserved ii