Consumer Product Safety

Accident Information Special News 25

May 24, 1999

Calling Attention of Body Fracture Accident in Using "Folding Bicycle"

By receiving the results of the test for settling the accident information performed by the National Institute of Technology and Evaluation based on the accident information of the "folding bicycle," the Ministry of International Trade and Industry officially announced the following contents on the calling attention of the body fracture accident in using a "folding bicycle" in May 24, 1999.

1. Outlines

In June 24, 1998, there was an accident in driving on a road surface in wards section in Tokyo that the frame of a so-called "folding bicycle" was suddenly broken and the rider's body was thrown out to be injured on the hands and legs. In November 27, 1998, accident information was sent to the competent Ministry, that in driving on a road surface in Chiba City, the frame was suddenly broken, and the rider's body was thrown out to break the clavicle. The both of the "folding bicycles" used were same brands and types.
The appropriate "folding bicycle" which is so called a mountain bike type bicycle**has a structure capable of folding the frame, is 26 inch type with 18-step derailleur, and sold at 30,000 yen in a mass merchandise outlet.

  • **Mountain bike type bicycle: Bicycle designed to be used solely on a general road and having a shape similar to that of the mountain bicycle.
    (Mountain bike: A bicycle capable of responding to a wide range riding including the traveling in a wasteland and a mountainous region.)

The sales company of the same type bicycle of the appropriate product was supposed to be Mishima Ringyo Co., Ltd. so that the National Institute of Technology and Evaluation in the Ministry of International Trade and Industry obtained the products of the same type and performed the test for settling the accident information. The test result showed that, if the appropriate "folding bicycle " is continuously used, the welding portion between the frame pipe of the folding port and the plate will be fractured. The accident occurred because the welding portion of the folding part of the frame has insufficient strength, and the welding metal is not uniformly applied, thereby, along with the insufficient strength, resulting into fracture by only about 2.5-month use.
It is so judged that if the appropriate type "folding bicycle" is continuously used for a long period, the crack in the welding portion of the folding part develops to bring about the fracture during using it, the user will be tumbled down and there is a possibility that, in the worst, a serious injured accident may occur.
According to the information grasped by the competent Ministry, another import and sales route other than the Mishima Ringyo Co., Ltd sold similar products to the appropriate type and it is highly possible that even at present, 10,000 or more bicycles are used by the general consumers.
Thereby, to prevent the accident from reoccurring, the competent Ministry call the attention of the consumers using the appropriate type "folding bicycle" to immediately check the bicycle.

(Target Product)

Product name:
Folding bicycle (mountain bike type bicycle)
Brand and model:
YAMATO YHC-FD MTB 2618
or MTB-FD2618
Sales company:
Mishima Ringyo Co., Ltd. (note 1)
3-173-1 Hishino Akanebe Gifu-shi, Gifu Prefecture
TEL058-273-5241 (the main switchboard number)
Manufacturer:
YUAN FEY INDUSTRY CO., LTD.
1089 Gokoji Unichigo Taichu Taiwan-sho
Period of sales:
After May 1996
Number of sales:
Approximately 2,000
Number of accidents:
2 cases
(Note 1)
This is the import and sales company grasped by the Ministry of International Trade and Industry at present and there is a possibility of other companies importing and selling it. Similarly, there is a possibility of existing the brand name YUAN FEY of the same type (MTB-FD2618) handled by other companies except for the Mishima Ringyo Co., Ltd.
(Problems of the products)
The test results of the accidental products and products identical with the accidental products showed that the fracture portions of the products causing the accidents are the welding portions between the frame pipes and the plates and there is deformation in the joint parts between the pipes and the plates. The welding metal by the welding was not applied uniformly on the circumference of the joint part and in some of them, there were parts with welding ranges partially narrow and with no welding metal.
The vibration resistances (frame strength) of the identical products were examined by the standards(note 2)of the mountain bike type bicycle to find that the same portion to the fracture portion of the accidental products were extremely deformed at the vibration application frequency 45,000.
Based on the matters mentioned above, it is concluded that the origins of the accidents were strength insufficiency in the welding portion of the folding part of the frame, non-uniform application of welding metal, and strength insufficiency, thereby being fractured only by about 2.5-month use.
(Note 2)
Standards of the mountain bike type bicycle
Frame for the bicycle (attached document) of Japan Industrial Standard (JIS D 9401)
"Strength of frame used for the mountain bike type bicycle" 2.1 vibration resistance
Itis not allowed to cause fracture, extreme deformation, and distortion in respective parts of the frame at the vibration application frequency 150,000.

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2. Outlines of Accidents Using Appropriate "Folding Bicycle"

  1. (1)In June 24, 1998, in driving on a road surface in wards section in Tokyo, the frame of a bicycle was suddenly broken and the rider's body was thrown out and injured on the hands and legs.
    Information Provider:
    Edogawa Ward Consumer Center
    Date of Providing Information:
    June 25, 1998
  2. (2)In November 27, 1998, in driving on a road surface in Chiba City, the frame of a bicycle was suddenly broken, and the rider's body was thrown out to break the clavicle.
    Information Provider:
    Japan Consumers' Association
    Date of Providing Information:
    December 14, 1998

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3. Matters Required Attention

Taking account of the accident information collected to the competent Ministry so far and the test results for settling the accident information, this "folding type bicycle" is so estimated that the welding portion of the folding part of the frame has insufficient strength, and if it is continuously used for a long period, the crack in the welding portion between the frame pipe and the plate of the folding part develops to bring about the fracture during using it, the user will be tumbled down and there is a possibility that, in the worst, a serious injured accident may occur. From the viewpoint of preventing the accident from occurring and reoccurring, it is necessary that the user of the "folding type bicycle" of the appropriate model immediately has the bicycle inspected by the sales company, etc.

Mountain Bike Folding Type Bicycle

Object bicycle photograph

Brand:
Mountain Bike Folding Type Bicycle
Model:
YH-FDMTB2618
orMTB-FD2618
Manufacturer :
YUAN FEY INDUSTRY CO.,LTD
(Taiwan)

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