GB/T 19994-2026General technical requirements for bicycles (English PDF)

4.2 Bicycle Structural Design Parameters

4.2.1 Bicycles are designed according to different uses.

4.2.2 Bicycle design should conform to ergonomics, with sufficient clearance between moving and stationary parts, and the riding and handling should be safe, comfortable, and convenient. Its main... For design parameters, please refer to A.1 in Appendix A.

4.2.3 The width of a bicycle handlebar should not exceed 1000mm. The handlebar width should be designed according to the different uses of the bicycle. The parameter values can be found in A.2.

4.2.4 The width of bicycle tires should be designed according to the different uses of bicycles. The design parameter values can be referred to A.3.

4.2.5 When bicycle products leave the factory, the manufacturer shall provide technical parameters consistent with the product specifications. Specific items can be found in Appendix B.

4.3 Reflector The reference axes of the mirrors of the front and rear reflectors mounted on the bicycle should be aligned with the front and rear of the bicycle, respectively. The vertical and horizontal installation angle error should not exceed 5°.

4.4 Horn device The bell wrench or buzzer button mounted on the bicycle should be in a location easily accessible to the rider.

4.5 Kettle Holder A water bottle cage installed on a bicycle should allow for easy access to the water bottle without it falling off while the bicycle is being ridden.

4.6 Vehicle air pump The bicycle pump holder should allow for easy access to and from the pump without interfering with riding the bicycle. It fell.

4.7 Quick-release device Quick-release devices installed on bicycles should have a limit structure or marking at the locking position, and the locking mechanism should be clearly indicated in the instruction manual. Force value.

4.8 Bicycle Construction A fully assembled bicycle should meet the following requirements.

a) The central shaft assembly has appropriate tension and rotates flexibly.

b) The saddle tube is locked with clamping bolts, and when the bolts are loosened, the saddle tube can move up and down easily.

c) The transmission system must not come into contact with other parts when rotating; its clearances must meet the following requirements. 1) Urban and touring bicycles, youth bicycles, and mountain bikes must be at least 6mm thick; 2) The thickness of the racing bicycle should not be less than 4mm.

5.1 Braking System

5.1.1 Brake operating performance When tested according to the method described in 6.1.1, after applying a gripping force to the brake lever, the brake pads should be able to touch the wheel rim, and after releasing the brake lever, the brake pads should... It should be able to detach from the rim immediately; during the test, the brake control cable should not interfere with the stop bolt, the movement should be smooth, and there should be no friction with the fixed object. The gap between the clamp-type gate arm and the adjusting screw should be greater than 10mm. The vertical adjustment range of the gate skin should be greater than 2mm.

5.1.2 Braking fatigue After testing according to the method described in 6.1.2, there should be no contact between the brake lever and the handlebar grip; the hydraulic brake system should have no oil leakage; the brakes should function properly. The braking performance should not be less than 60% of the braking performance at the maximum operating force recorded before the braking fatigue test.

5.2 Drive System

5.2.1 Drive system impact After testing according to the method described in 6.2.1, the drive system should not lose its function, any component should not break, and the drive belt should not have any broken teeth.

5.2.2 Foot pedal installation reliability After testing according to the method described in 6.2.2, the disengagement torque of the pedal shafts of the left and right pedals should not be less than 25 N·m.

5.3.1 Reflecting Device

5.3.1.1 Front Reflector After testing according to the method described in 6.3.1.1, the bicycle front reflector mirror or mirror frame should not touch the ground.

5.3.1.2 Rear Reflector After testing according to the method described in 6.3.1.2, the bicycle rear reflector mirror or mirror frame should not touch the ground; for components susceptible to external forces... When force is applied to the rear reflector, the deviation of its mirror reference axis should be less than 15°; after the force is released, the deviation of its mirror reference axis should be less than 5°, and its various... The part should be free from damage and other obvious defects.

5.3.1.3 Foot pedal reflector The pedal reflector should be securely embedded in the pedal body or reflector frame and subjected to an impact test as described in 6.3.1.3. The pedal reflector should not detach.

5.3.2 Lighting devices

5.3.2.1 For bicycles equipped with low beam headlights, after testing according to the method described in 6.3.2, the leading edge of the light spot illuminating the horizontal road surface... The vertical distance between the centers of the front wheels should not exceed 8m.

5.3.2.2 For bicycles equipped with high beams, after testing according to the method described in 6.3.2, the leading edge of the light spot illuminating the horizontal road surface... The vertical distance between the centers of the front wheels should not exceed 16m.

5.4.1 Clay Tablets

5.4.1.1 The center line of the mounting holes for mudguards (mudguard tabs) on the bicycle front fork and frame should be located on the center plane of the frame.

5.4.1.2 The gap between the front and rear mudguards and the front and rear wheels of the bicycle shall be measured at three points, and the difference between the measured values shall be less than 4 mm.

5.4.1.3 The rear mudguard installed on the bicycle should not be noticeably twisted.

5.4.2 Luggage rack When a luggage rack is installed on a bicycle, it shall be tested according to the method described in 6.4.2.The luggage rack platform shall be tilted horizontally at 0° to 4° towards the riser.

5.4.3 Bracket

5.4.3.1 When a bracket is mounted on a bicycle, after supporting the bicycle, the support rod of a single bracket should extend forward within the range of 10mm to 25mm. Inside, the support rods of the double brackets should be tilted forward at 3°~7°.

5.4.3.2 For single-bracket installations on bicycles, the rear single-bracket, when in place, should tilt the bicycle towards the bracket at an angle of 8°~12°. (Middle single-bracket...) After being propped up, the bicycle should tilt at an angle of 6° to 11° towards the support.

5.4.3.3 When the double-stand parking bracket installed on the bicycle is raised, the distance between the front or rear tire of the bicycle and the ground should be greater than 30mm.

5.5.1 Overall Vehicle Reliability

5.5.1.1 Vehicle tipping over After testing according to the method described in 6.5.1.1, the bicycle's lights and reflectors should be undamaged and able to be ridden normally.

5.5.1.2 Vehicle Steering Rigidity After testing according to the method described in 6.5.1.2, the steering stiffness value of the bicycle should meet the requirements of Table 1. Table

1.Bicycle Steering Stiffness Values The unit is Newtons per millimeter. Types of bicycles. City and touring bicycles, youth bicycles, mountain bikes, racing bicycles Stiffness K value >=4 >=4 >=5 >=5.5

5.5.2 Vehicle Handling

5.5.2.1 Derailleur sensitivity When tested according to the method described in 6.5.2.1, the bicycle manual shifter completes any gear change when the gear ratio between the sprocket and the freewheel is greater than 1. When the ratio of the number of teeth on the sprocket to the number of teeth on the flywheel is less than 1, the rotation angle of the drive crank should not exceed 180°; when the ratio of the number of teeth on the sprocket to the number of teeth on the flywheel is less than 1, the rotation angle of the drive crank should not exceed 180°. At 360°.

5.5.2.2 Wheelset Rotation Performance After testing according to the method described in 6.5.2.2, the bicycle wheel valve should be at the lowest position of the wheel assembly.

5.5.2.3 Impact of front and rear wheels landing After testing according to the method described in 6.5.2.3, the support rod of the bicycle frame should not be in contact with the ground, and the chain and chain guard should not collide.

5.5.3 Fork assembly fatigue After testing according to the method described in 6.5.3, the rotating part of the bicycle front fork assembly should not show obvious looseness or abnormal rotation, and the steel balls and upper and lower cup surfaces should be intact. The surface should be free of pits.

5.5.4 Relative deviation between the center planes of the front and rear wheels After testing according to the method described in 6.5.4, for bicycles with a tire width not exceeding 40mm, the relative deviation between the center planes of the front and rear wheels is... The deviation should not exceed 4mm; for bicycles with a tire width greater than 40mm, the relative deviation between the center planes of the front and rear wheels should not exceed 7mm.

5.5.5 Vibration test of frame and fork assembly After testing according to the method described in 6.5.5, the bicycle frame should have no visible cracks or breaks, no obvious deformation or loosening, and the shock absorption system should be intact. No parts should be separated.

5.5.6 Parallelism of the derailleur hanger on the frame Measured according to the method described in 6.5.6, the parallelism of the frame derailleur hanger should meet the requirement that |LC-LD| is not greater than 10mm. The requirement is that the thickness of the LA-LB should not exceed 10mm.

5.6 Appearance

5.6.1 Surface Coating After testing according to the method described in 6.6, the vehicle surface coating should be smooth and free from defects such as exposed substrate, runs, pinholes, orange peel, or aggregated particles. defect.

5.6.2 Decals After testing according to the method described in 6.6, the decorative decals should be flat and clear, and free from defects such as damage, bubbles, wrinkles, and cracks.

6.1 Braking System Test Methods

6.1.1 Brake operating performance After applying a braking force of no more than 44.5N to the brake lever, visually inspect the contact between the brake pads and the wheel rim; release the brake. After applying and releasing the brake lever, check if the brake pads rebound and detach from the rim in a timely manner; check if the brake control cable is smooth during the application and release of the brake lever; adjust the clamp brake by hand. Adjust the brake control line adjustment screw on the boom to adjust the vertical distance of the brake pads. Use a ruler to measure whether the adjustment distance meets the requirements of 5.1.1.

6.1.2 Braking fatigue The fully assembled bicycle is installed on a testing machine according to the requirements of

4.6.5.4 in GB/T 3565.4-2022, and the brakes are installed according to... The method described in GB/T 3565.4-2022, 4.6.5.7c)1), is used to conduct a dry braking performance test on the vehicle brakes, and the braking force under maximum operating force is recorded. Force value. Then continue driving the wheels and tire assembly at a speed of 12.5 × (1 ± 5%) km/h, with the rear cooling airflow speed at 12.5 × Braking force is applied at (1±5%) km/h. The braking force value generated by each applied braking force is shown in Table 2, and the braking force is maintained for each time. The interval is 3.0s, and the interval between the second braking operation force application is 15s~20s, and the braking operation force is applied repeatedly for 3000 times.

6.2 Test Methods for Drive Systems

6.2.1 Drive system impact The bicycle (at least the frame, bottom bracket assembly, chainring and crank assembly, chain or drive belt, freewheel, derailleur, and rear wheel/tire assembly) The saddle tube and saddle seat are assembled and installed on the testing machine. The rear wheel is placed on the roller, and a load of 70 kg is applied to the saddle seat (to prevent the tire from slipping during the test). Based on the principle, a damping of

12.5 N·m is applied to the roller, and a torque of 120 N·m is applied to the central shaft to drive the rear wheel to rotate. When the rear wheel reaches 15... At a linear speed of km/h, stop applying torque to the bottom axle. Resume applying torque to the bottom axle after the rear wheels stop rotating. This process involves applying and unloading torque. One impact cycle consists of 10,000 consecutive impact cycles. After the test, check the function of the drive system and inspect each component for any issues. damage.

6.2.2 Foot pedal installation reliability Apply a torque of 25 N·m to the pedal shaft in the direction of detachment using a torque wrench, and observe whether there is any looseness in the connection between the pedal and the crank.

6.3.1 Reflecting device

6.3.1.1 Front Reflector When a bicycle equipped with a front reflector is placed on the ground in any position, visually inspect the front reflector mirror or reflector. Will the mirror stand touch the ground?

6.3.1.2 Rear Reflector When a bicycle equipped with a rear reflector is placed on the ground in any position, check whether the rear reflector mirror or mirror holder touches the ground. Touch. Apply a force of 90N (50N for rear reflectors mounted on mudguards) to the rear reflector, which is susceptible to external forces, and hold for 30 seconds. An angle measuring instrument is used to check if the deviation of the mirror's reference axis is less than 15°. After unloading, the deviation of the mirror's reference axis is checked to see if it is less than 5°. Visual inspection is also performed. Check all parts of the rear reflector for damage or other obvious defects.

6.3.1.3 Foot pedal reflector Place the bicycle smoothly on a flat, simulated ground surface, with the handlebars symmetrical to the center plane of the frame, and one pedal at its highest position. Place the bicycle 15° towards the highest point of the pedals and then freely tilt it onto the simulated ground surface. Repeat this tilting motion 5 times. Visually inspect the pedal reflectors for any issues. Shedding.

6.3.2 Lighting devices Place the bicycle smoothly on a flat, simulated ground surface, with the handlebars symmetrical to the center reference plane of the frame. Turn on the headlight switch and measure the front axle. The distance from the center to the edge of the light source.

6.4.1 Clay Tablets

6.4.1.1 Visually inspect the position of the center line of the mounting holes on the mudguards (mudguard connectors) installed on the bicycle.

6.4.1.2 After inflating the tires to the minimum of the manufacturer's recommended maximum inflation pressure, measure the mud pressure on the bicycle. Measure the gap between the wheel and the mudguard at 20mm from each end of the mudguard, then measure the gap between the mudguard and the wheel at the middle of the mudguard. Then measure these three... Subtract the measured values from each other and check if the three differences meet the requirements.

6.4.1.3 Visually inspect the appearance of the rear mudguard installed on the bicycle.

6.4.2 Luggage rack Place the bicycle with the luggage rack mounted smoothly on a flat, simulated ground surface, with the handlebars symmetrical to the center plane of the frame. Then place the bicycle on the luggage rack. Place a simulated flat surface, put an angle meter in the middle of it, and observe whether the angle of the luggage rack tilting towards the upright tube meets the requirements.

6.4.3 Bracket

6.4.3.1 Place the bicycle with the mounting bracket smoothly on a flat, simulated ground surface. After setting up a single (or double) bracket, position the handlebars symmetrically. Using the frame center reference plane, measure the vertical distance from the center of the top of the support rod of a single bracket to the center of the bottom of the support rod to see if it meets the requirements; or measure the distance between the two brackets. Does the angle between the center reference plane of the frame and the vertical plane meet the requirements (the angle between the center of the frame riser and the vertical plane)?

6.4.3.2 Place the bicycle with the single frame mounted stably on a flat, simulated ground surface, with the handlebars symmetrical to the center reference plane of the frame, and support the single frame. After mounting the bracket, measure whether the angle between the center reference plane of the frame and the vertical plane meets the requirements.

6.4.3.3 Place the bicycle with the double-bracket mount stably on a flat, simulated ground surface, with the handlebars symmetrical to the center reference plane of the frame, and raise the brackets. After setting up the frame, measure the distance between the front or rear tires and the ground to see if it meets the requirements.

6.5.1 Overall vehicle reliability

6.5.1.1 Vehicle tipping over Inflate the tires to the minimum recommended maximum inflation pressure by the manufacturer, then park the bicycle smoothly on a flat, simulated surface. On a flat surface, the handlebars are symmetrical to the center plane of the frame, and the left and right pedals are on the same horizontal plane, with the right pedal at the back. Tilt the bicycle towards the chain side. After tilting at a 15° angle, the vehicle is allowed to freely tilt onto a simulated ground surface. This is repeated five times. The vehicle's condition is then checked using visual inspection and riding methods to verify compliance with regulations. Require.

6.5.1.2 Vehicle Steering Rigidity Assemble the frame and fork as recommended by the manufacturer, then install the front wheel (excluding the tire) onto the fork, following the manufacturer's instructions. Tighten to the recommended torque and secure the frame joint to the rigid clamp in its normal position, as shown in Figure

3.First, tighten the two spokes at the front wheel contact point. Apply a 20N preload to the left (avoiding the air nozzle area). After stabilization, use this as the deformation displacement reference point, and then slowly apply the load. Apply 125 N and hold for 1 minute or longer to allow the deformation to stabilize. Measure the lateral displacement of the wheel rim under this load. (125N-20N=105N) divided by the displacement gives the steering stiffness K value on the left side. Remove the load to the left, and gently push or pull the wheel left and right to allow it to return to its proper position. Then, apply pressure to the wheel to the right from the same position. Apply a 20N preload and, after stabilization, use this as the reference point for deformation displacement. Then, slowly increase the load to 125N and hold for 1 minute or longer. To allow the deformation to reach a stable state, measure the lateral displacement of the wheel rim under this load, calculate the steering stiffness K value on the right side, and take the flat values on both sides. The mean value is the vehicle steering stiffness K value. Indexing symbol explanation. A

---The point of force application and the reference point for deformation displacement. Figure

6.5.2 Vehicle Handling

6.5.2.1 Sensitivity of the gearshift chain Secure the fully assembled bicycle to the stand. With the bicycle stationary, check the gear ratio between the sprocket and freewheel, shift the gear lever, and rotate the crank. Visually observe the crank angle when the derailleur is engaged or disengaged.

6.5.2.2 Wheelset Rotation Performance Lift the front and rear wheels of the fully assembled bicycle off the ground, rotate the slewing mechanism, and visually inspect the valve positions of the front and rear wheels. Check if the settings meet the requirements.

6.5.2.3 Impact of front and rear wheels landing Inflate the tires of a fully fitted bicycle to the minimum of the manufacturer's recommended maximum tire inflation pressure, then position the handlebars symmetrically on the bike. After setting up the center reference plane, lift the front and rear wheels 300mm each and then let them land vertically and freely. Visually check whether the support rods of the bracket are in contact with the ground. And; whether the chain collides with the chain guard.

6.5.3 Fork assembly fatigue As shown in Figure 4, the fork assembly is installed on a representative rigid front tube and fork seat tube, and a flat-type fork assembly is installed on the fork seat tube. Apply a 20kg load to each side of the horizontal tube. Drive the horizontal tube via a drive pulley connected to an electric motor. Rotate left and right (-50° to 50°) at a frequency of 10 to 15 times per minute. One rotation to the left and right constitutes one cycle, and 100,000 rotations are performed continuously. Cycle. After the test, check the fork assembly by hand for any looseness or abnormal rotation. Remove the fork assembly and visually inspect the steel balls and upper and lower cup surfaces. Condition.

6.5.4 Relative deviation between the center planes of the front and rear wheels Inflate the tires of a fully assembled bicycle to the minimum recommended maximum tire inflation pressure by the manufacturer, then attach the special tool wheel. The rim clips are fastened to the farthest rims of the front and rear wheels, forming a horizontal line with the centers of the front and rear axles (see Figure 5). On the other side of the rim clips... At a specified distance *c* from the wheel rim on one side, draw a horizontal line parallel to the rear wheel plane (making *a* = *b*). Adjust the front wheel so that *d* (or *c*) is equal to *a* and *b*. If points are aligned in a straight line, the distance c (or

d) between points not on the line and a (or

b) is the center deviation, which is then divided by 2.

6.5.5 Vibration test of frame and fork assembly After assembling the frame with the test fork, fork assembly, and seat tube, it is mounted on a dedicated test bench. During frame installation, the axles of the front and rear wheels are aligned... Horizontal, as shown in Figure

6.If using a frame with front and rear wheel diameters different, the wheel contact points should be at the same horizontal level. (For vehicles with seat tubes...) For the frame test piece, fix the seat tube at the minimum insertion depth mark, and then, as shown in Figure 7a), install a saddle-shaped load seat at the saddle seat, and then... A circular counterweight is suspended from the left and right booms. The total weight of the load seat, booms, and counterweights should meet the specified load capacity. The load seat is secured with clamps. The center position is 20mm from the top of the saddle tube. A circular weight is used for the load at the center axis, fixed on both sides of the center axis. The load at the front tube... As shown in Figure 7b), tighten the counterweight and counterweight seat onto the front tube using the fastening nut. Set the vibration acceleration and vibration frequency of the test bench, and start... Vibration tests were conducted on a dynamic test bench. Test conditions are given in Table

3.The maximum test frequency should comply with section

4.5 of GB/T 3565.3-2022. Requirements.

6.5.6 Measurement of parallelism of derailleur hanger lugs on the frame Install the necessary components of the external transmission system onto the appropriate frame according to their intended use, and correct the wheel axial runout and installation gap. After ensuring the clearance meets the relevant requirements of GB/T 3566, suspend the frame on the measuring platform and keep it stationary, with the frame's center reference plane perpendicular to the ground, and the rear wheel... The center plane coincides with the center reference plane of the frame. As shown in Figure 8, after the special tool is tightly fitted to the mounting surface of the derailleur lug, the special tool is moved around the center of the mounting surface of the derailleur lug. Rotate the wheel one full turn and measure the distances between the top, bottom, left, and right ends of the bicycle rim (at its maximum diameter) and the special tool. The values of LC, LD, LA, and LB shall be calculated in accordance with the requirements of 5.5.6.

6.6 Appearance Inspection Visual inspection should be used to check whether the surface coating, decals, and coding of a fully assembled bicycle meet the requirements.