Bicycle safety performance

Bicycle rider 's personal safety is an important issue , there are countries to develop appropriate standards . China promulgated safety standards include three aspects strength structural parts , brake brake performance and safety devices , including the strength of the former frame and fork assembly , the assembly of the handlebar firmly with fork , front and rear wheel strength .
① impact strength frame and fork assembly : There are two measurement methods. First, the drop weight impact test, the assembly is erected vertically , the top of the front fork 180mm 22.5kg Battery powered bikes disposal a hammer , a hammer impact on the permanent deformation of the assembly does not exceed 40mm, no naked eye crack ; Second, drop test , placing 70kg weights in the saddle at the component, its center of gravity moved to the vertical position of the rear axle , the free fall forward , repeat the test twice , without naked eye cracks. In addition, the frame and fork need for lateral load strength test , the load weight varies by model .
② handlebar assembly firmness and fork : The method is the handlebar mount fork, 25N · m of torque applied to the handlebars womens mountain bikes horizontal pipe ( usually test bars instead) , the handlebar can not rotate.
Before ③, the strength of the rear wheel : The method is to put the corrected wheel spokes and clamping flat , 178N force is applied laterally , one minute later , the permanent deformation of not more than 1.5mm.
④ brake brake performance: test method according to the vehicle 's transmission ratio is divided into two kinds. One is on the trip 5m 5m or more bikes , the specified test speed of 24km / h; another one is on the trip 5m below the car, the speed of 16km / h. There are two wet braking performance and analog dry rainy . In the test speed required before use , the brake , the braking distance is not greater than the dry 5.5m, wet braking distance shall not exceed 15m.
⑤ safety devices: a bicycle should be equipped with a bell or lights , but also a reflector ( commonly known as the back light ) . The reflector is by vehicle headlights or other external light source , the intensity of the reflected light enough to remind each other's attention to protect themselves. The reflector has a front , side and rear reflector 3 kinds . In front of the white, red rear , front lateral white or amber , rear lateral white or red , white or amber pedal .