Not for Resale ISO INTERNATIONAL 9987 STANDARD First edition 1990-12-15 Motorcycles --- Measurement of variation of dipped beam inclination as a function of load Motocycies -- Mesurage des variations d'inclinaison du faisceau de croisement en fonction de la charge Reference number IsO 9987:1990(E) ISO 9987:1990(E) Foreword IsO (the International Organization for Standardization) is a worldwide federation of national standards bodies (lsO member bodies). The work of preparing International Standards is normally carried out through IsO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, govern- mental and non-governmental, in liaison with sO, also take part in the work. Iso collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. Draft International Standards adopted by the technical committees are clrculated to the member bodies for voting. Publication as an Inter- nationat Standard requires approval by at least 75 % of the member bodles casting a vote. International Standard IsO g987 was prepared by Technical Committee ISO/TC 22, Road vehicles. Annex A forms an integral part of this International standard. Annexes B and C are for information only. ISO1990 or by any means, electronic or mechanical, including photocopying and microtilm, without permlsslon In writing from the publlsher. international Organization for Standardization Case Postale 56 CH-1211 Genéve 20 Switzerland Printed In Switzerland ternational Organization for Standardization Not for Resale se from IHS ISO 9987:1990(E) INTERNATIONAL STANDARD Motorcycles --.. Measurement of variation of dipped beam inclination as a function of load 3.1 dipped beam inclination: Inclination, for meas- Scope uring the dipped beam variation for which it is nec- essary to choose only one reference point within the This International Standard specifies a method of luminous distribution in the beam, defined measuring the variation of motorcycle dipped beam inclination, with respect fo its initial inclination, either as the angle, expressed in milliradians, caused by the changes in vehicle attitude due to between the direction of a characteristic point. loading. chosen by the manufacturer,in the luminous The loading conditions of the vehicle are distribution of the headlamp and the horizontal NOTE specified in annex A. plane; It applies to two-wheeled motorcycles as defined in or by the tangent of that angle, expressed in percent inclination (since the angles are small ISO 3833. 1 % is equal to 10 mrad). If the inclination is expressed in percent inclination Normative references [with negativevalues denotingdownward incli- nation and positive values denoting upward incli- The following standards contain provisions which, nation (see figure 1l, it can be caiculated from the through reference in this text, constitute provisions following formula: of this International Standard. At the time of publi- h, -- hz cation, the editions indicated were valid, All stan- × 100 dards are subject to' revision, and parties to agreements based on this International Standard are 'encouraged to investigate the possibility of ap- where plying the most recent editions of the standards in- dicated below. Members of IEC and ISo maintain is the height above the ground, in milli- ht registers of currently valid International Standards. metres. of a characteristic point of the cut- off on the opposite side to trafficu, Iso 3833:1977, Road vehicles -- Types - Terms and measured on a vertical screen perpendic- definitions. ular to the vehicle longitudinal median plane, placed at a horizontal distance l; Iso 6726:1988, Mopeds and motorcycles with two is the height above the ground, in milli- wheels -- Masses --. Vocabulary. hz metres, of . the reference' centre of the headlamp; IsO 7227:1987, Road