Bicycle Consumer Advocacy


				Bicycle Reform Awareness



	Bicycle Frame Safety Evaluation \| Notice of Dangerous Condition \| DIY Bicycle Wheel Building VS BUYING Wheels \| Tires & Tubes \| Health

Bicycle Safety to Consider Before Purchase, Customization, Refurbishing, and Ridding!

AVOID the danger of unexpected FRAME-WHEEL SEPERATION.

Look to evaluate a bicycle for potential hazard.

If a bicycle frame is constructed with open front rear dropouts, frame-wheel seperation is likely.

LOOK ?

If a bicycle frame is constructed with open front rear dropouts, it is possible for the action of pedaling alone to pull one side of the rear wheel axle loose and forward, stopping the rear tire against the inside of the bicycle frame against a chain stay. The action may immediately and suddenly stop the bicycle, or cause rubbing of the rear tire against the bicycle frame. Reliable transportation? Reliable recreational equiptment? Look and Learn enough to protect yourself from inadaquate mechanical design.

Persons whom have experienced an above described mechanical failure, particularly with new ORIGINAL EQUIPMENT, please contact ohallock@yahoo.com to confirm witness to the problem, to promote safer bicycle rule making at the national level, and, or

Better yet ANYONE INTERESTED, PLEASE visit DROPS Petition http://www.ipetitions.com/petition/DROPS/and read The Public Comment Petition and sign it, if you feel it is a valid pursuit. The Public Comment Petition is to suggest to the Consumer Product Safety Comission Washington DC to phase out use of open front horizontal drops on street bicycle frame construction.

Bicycle Safety to Consider Before Purchase,

Customization, Refurbishing, and Ridding

What can cause a bicycle to stop unexpectedly?

         an off chain,

         a tire rubbing or pressing against the frame,

         a chain caught or jammed between parts of a bicycle.

Every one expects chain problems from a bicycle. Most never consider coming to a screeching stop, unexpectedly in front of oncoming cars, or dream that it is a distinct possibility for a child or adult riding a bicycle. Clearances between the frame of a bicycle and the moving parts of a bicycle are important. Bicycle frame and component construction directly relate to the possibility of unexpected stopping. The more a failure prone bicycle is ridden the greater the chance of failure.

To evaluate a bicycle for unexpected hazard look at the bicycle

FRAME.

    Look where the rear wheel is attached to the bicycle frame between two opposing rear dropouts. There are three basic styles of rear dropouts, open front, open back, and open bottom.

    If a bicycle frame is constructed with open front rear dropouts, it is possible for the action of pedaling alone to pull one side of the rear wheel axle loose and forward, stopping the rear tire against the inside of the bicycle frame against a chain stay. The action may immediately and suddenly stop the bicycle, or cause rubbing of the rear tire against the bicycle frame.

    A bicycle rear wheel axle loosened and pulled forward by the power of pedaling, while one end of the axle remains fixed to the bicycle, may be subject to deformation that can lead to unexpected stopping of the bicycle, due to breakage of the rear axle, at a later time. A solid bicycle rear axle is more likely to pull out of open front rear dropouts than a hollow quick release wheel axle, and a strong rider traversing hilly terrain is more likely to cause forward pullout of one side of the rear wheel axle from the frame, than a casual rider.

    Look at the bicycle where the rear gear changer is fastened to the bicycle frame. If the rear gear changer is fastened to the bicycle frame, via a HOOKED bolt on hanger of the type mounted on one end of the rear wheel axle, and clamped beneath the rear axle fastener, the chances of forward pull out of one side of the rear bicycle wheel axle from an open front rear drop out bicycle frame during pedaling is more probable.

    Forward pull out of one side of the rear wheel axle may occur with other styles of dropouts. Forward pull out of the geared drive chain side of the axle is the most likely.

    Once forward pull out of one side of the rear wheel axle from an open front rear dropout type bicycle frame occurs during riding, it is unlikely to be an isolated incident that can be prevented from unexpectedly occurring again. Forward pull out of one side of the rear wheel axle may occur with other styles of dropouts. Forward pull out of the geared drive chain side of the axle is the most likely.

SIMULATION

    Forward pull out of one side of the rear bicycle wheel axle can be simulated by loosening the axle fastener of the rear bicycle wheel on the chain side, then attempt to pedal forward. This simulation will exemplify forward pull out and indicate the magnitude for a given bicycle, and exemplify its existence, and is likely to bend the axle.

CHAIN CLEARANCES

    Look at the space between the sidewall of the rear bicycle tire and the inside of the lower bicycle frame, where it passes the rear tire. See if an OFF chain will loosely pass between the tire sidewall and the inside of the bicycle frame, without possibility of the chain jamming between the tire and frame, stopping the rotation of the rear wheel. The lower bicycle frame members supporting the rear wheel of a bicycle are termed the chain stays. A bicycle frame constructed open bottom rear drop outs with crimped chain stay frame members, inside adjacent the rear tire can usually eliminate the possibility of a bicycle coming to an unexpected screeching stop, caused by a OFF chain, jamming between the rear tire sidewall and the inside of the bicycle frame.

    Unexpected stopping due to mechanical failure is more likely with strong frequent riders when stresses are the greatest on the bicycle and rider, in areas of change, in and around intersections, and elevation changes, such as hills.

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Horizontal rear dropouts can be unreliable and should be considered bad practice for multigeared bicycles. Vertical rear dropouts can provide a more reliable margin of safety.

Rear dropouts are located at the rearmost lower end of the rear triangle of a diamond frame safety bicycle, and most other bicycle frames. Rear dropouts are slots to either side of the bicycle frame in which the rearwheel axle seats, and is where the rearwheel is secured to either side of the bicycle frame. Dropouts are made so the bicycle wheels can be easily removed from the bicycle, for wheel or tire maintenance, or to make the bicycle smaller for packing or storage.

Vertical Rear Dropout w/ Horizontal Rear Dropout w/ Horizontal Rear Dropout w/o Rear Derailleur Hanger Rear Derailleur Hanger Rear Derailleur Hanger