EN 14781:2005

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Racing bicycles - Safety requirements and test methodsTekmovalna kolesa – Varnostne zahteve in preskusne metodeBicyclettes de course - Exigences de sécurité et méthodes d'essaiRennräder - Sicherheitstechnische Anforderungen und PrüfverfahrenTa slovenski standard je istoveten z:EN 14781:2005SIST EN 14781:2006en97.220.4043.150ICS:SLOVENSKI
STANDARDSIST EN 14781:200601-september-2006

EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 14781November 2005ICS 43.150 English VersionRacing bicycles - Safety requirements and test methodsBicyclettes de course - Exigences de sécurité et méthodesd'essaiRennräder - Sicherheitstechnische Anforderungen undPrüfverfahrenThis European Standard was approved by CEN on 7 October 2005.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the Central Secretariat or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre: rue de Stassart, 36
B-1050 Brussels© 2005 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 14781:2005: E

Explanation of the method of least squares for obtaining line of best fit
and ± 20 % limit lines for braking performance linearity.76 Annex B (informative)
Steering geometry.79 Bibliography.80

3.27 lowest gear gear ratio which gives the shortest distance travelled for one rotation of the cranks 4 Requirements and test methods 4.1 Brake tests and strength tests – special requirements 4.1.1 Definition of brake tests Brake tests to which accuracy requirements apply, as in 4.1.4, are those specified in 4.6.2.2.3 to 4.6.6.2 inclusive and 4.6.7.5.1.3. 4.1.2 Definition of strength tests Strength tests to which accuracy requirements apply, as in 4.1.4, are those involving static, impact or fatigue loading as specified in 4.7 to 4.13 inclusive and 14.17.2.

Forces and torgues……………
0/+5 %
Masses and weights……………± 1 %
Dimensions…………………….± 1 mm
Angles……………………………± 1°
Time duration……………………± 5 s
Temperatures……………………± 2 °C
Pressures………………….± 5 %
4.2 Sharp edges Exposed edges that could come into contact with the rider’s hands, legs etc., during normal riding or normal handling and normal maintenance shall not be sharp. 4.3 Security and strength of safety-related fasteners 4.3.1 Security of screws Any screws used in the assembly of suspension systems or screws used to attach generators, brake-mechanisms and mudguards to the frame or fork or handlebar, and the saddle to the seat- pillar shall be provided with suitable locking devices, e.g. lock-washers, lock-nuts, or stiff nuts. NOTE Fasteners used to assemble hub and disc brakes should have heat-resistant locking devices. 4.3.2 Minimum failure torque The minimum failure torque of bolted joints for the fastening of handlebars, handlebar-stems, bar-ends, seats and seat-pillars shall be at least 50 % greater than the manufacturer’s recommended tightening torque. 4.4 Crack detection methods Standardised methods may be used to emphasise the presence of cracks where visible cracks are specified as criteria of failure in tests specified in this European Standard. See 3.21. NOTE For example, suitable dye-penetrant methods are specified in ISO 3452.

Key R ≥ 6,3 A ≥ 12,7 B ≥ 3,2 Figure 1 — Examples of minimum dimensions of exposed protrusion (these apply when L is greater than 8 mm)
Dimensions in millimetres
Figure 2 — Exposed protrusion test cylinder

Key 1 Test cylinder 2 Protrusion shall comply 3 Protrusion need not comply Figure 3 — Examples of protrusions 4.5.2 Test method Conduct the test with a protrusion test cylinder (which simulates a limb) having the dimensions shown in Figure 2. Manoeuvre the test cylinder in all possible attitudes towards any rigid protrusion on the bicycle. If the central 75 mm long section of the cylinder contacts the protrusion, that protrusion shall be considered to be an exposed protrusion and it shall comply with 4.5.1.1. Examples of protrusions that need and do not need to comply with the requirements are shown in Figure 3. 4.6 Brakes 4.6.1 Braking-systems A bicycle shall be equipped with at least two independent braking-systems. At least one shall operate on the front wheel and one on the real wheel. The braking systems shall operate without binding and shall be capable of meeting the braking-performance requirements of 4.6.7. Brake-blocks containing asbestos shall not be permitted. 4.6.2 Hand-operated brakes 4.6.2.1 Brake-lever position The handbrake levers for front and rear brakes shall be positioned according to the legislation or custom and practice of the country in which the bicycle is to be sold, and the bicycle manufacturer shall state in the manufacturer's instructions manual which levers operate the front and rear brakes (see also Clause 5 b)).

Dimension in millimetres
Key
1 Pivot Figure 4 — Handbrake-lever grip dimensions

Key A = Face A B = Face of cylinder C = Rod
Figure 5 — Handbrake-lever grip-dimension gauge 4.6.2.2.2 Test method Fit the gauge illustrated in Figure 5 over the handlebar and brake lever as shown in Figure 6 so that the face A contacts the handlebar or handlebar-grip and the brake-lever. Put the face of cylinder B in contact with the part of the grip intended for contact with rider’s hand and check if the requirements are met.

Figure 6 — Method of fitting the gauge to the handbrake-lever and handlebar
Dimensions in millimetres
Figure 7 — Position of applied force on the handbrake-lever 4.6.2.3 Position of applied force For the purposes of all braking tests in this European Standard the test force shall be applied at a distance of
25 mm from the free end of the brake-lever (see Figure 7). 4.6.3 Attachment of brake assembly and cable requirements NOTE See 4.3 in relation to fasteners. Cable pinch-bolts shall not sever any of the cable strands when assembled to the manufacturer’s instructions. In the event of a cable failing, no part of the brake mechanism shall inadvertently inhibit the rotation of the wheel. The cable end shall either be protected with a cap that shall withstand a removal force of 20 N or be otherwise treated to prevent unravelling.

Braking distance m Dry 25 Both 6,00
Rear only 12,00 Wet 16 Both 5,00
Rear only 10,00
4.6.7.4.2 Smooth, safe stop-characteristics The bicycle shall show smooth, safe stop-characteristics. i) For the track test, smooth, safe stop characteristics are defined as stopping within the required distances without occurrence of any of the following: a) excessive juddering; b) front wheel locking; c) bicycle overturning (rear wheel lifting uncontrollably); d) rider's loss of control; e) excessive side-skid causing the rider to put his foot to the ground to retain control.

Key 1 Water-nozzles 2 Front crown 3 Front tee-piece 4 Wheel rim 5 Direction of wheel rotation Figure 8 — Water-nozzles for rim-brake (front)

Key 1 Water-nozzles 2 Rear tee-piece 3 Bicycle frame 4 Wheel rim 5 Brake assembly 6 Direction of wheel rotation Figure 9 — Water-nozzles for rim-brake (rear)

Key 1 Water nozzles 2 Two water-nozzle 3 Hub-brake 4 Direction of wheel rotation Figure 10 — Water-nozzles for hub-brake (front and rear)

Key 1 Water nozzles 2 Front hub 3 Flexible pipe 4 Suspension-fork leg 5 Y-joint 6 Brake disc 7 Disc-brake calliper 8 Direction of wheel rotation Figure 11 — Water-nozzles for disc-brake (front)

Key 1 Water-nozzles 2 Rear suspension frame 3 Rear hub 4 Y-joint 5 Brake disc 6 Disc-brake calliper 7 Direction of wheel rotation Figure 12 — Water-nozzles for disc-brake (rear)
4.6.7.5.1.7 Test method – test runs under wet conditions The method shall be as given in 4.5.7.5.1.6, with the addition that wetting of the brake system(s) shall commence not less than 25 m prior to the commencement of braking (3.10) and shall continue until the bicycle comes to rest. NOTE Excessive amounts of water may be swept from the test-track surface between runs. 4.6.7.5.1.8 Number of valid test runs I) If the gradient of the track is less than 0,2 %, the following runs shall be made: a) five consecutive valid runs under dry conditions; b) two acclimatization runs under wet conditions (results not recorded); c) five consecutive valid runs under wet conditions. II) If the gradient of the track lies between 0,2 % and 0,5 %, the following runs shall be made: a) six consecutive valid runs under dry conditions with alternate runs in opposite directions; b) two acclimatisation runs under wet conditions (results not recorded); c) six consecutive valid runs under wet conditions with alternate runs in opposite directions.

Sc is the corrected braking distance (m);
Sm is the measured braking distance (m);
Vs is the specified test velocity (m/s);
Vm is the measured test velocity (m/s). 4.6.7.5.1.10 Validity of test runs I) A test run shall be considered invalid if: a) excessive side-skid, causing the ride to put his foot to the ground to retain control, or b) loss of control
occur. With certain types of braking system, it may not be possible to avoid entirely some skidding of the rear wheel during braking: this is considered acceptable provided that a) or b) above do not occur as a result; II) If the corrected b
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