on 3/13/03 11:56 AM, MSCTROSE@aol.com at MSCTROSE@aol.com wrote:
>
> In a message dated 3/13/03 9:24:25 AM, goodrichbikes@netzero.net writes:
>
>
>> I've also had my brazing tested by several independent testing facilities.
>> Joe Starck and I built many forks for Rivendell for testing of a new fork
>> crown. It was quite interesting.
>>
>
> Curt
> Please tell us the testing procedure. Inquiring minds want to know. Is
> this procedure done for >gasp< modern, off topic, factory made forks as well?
There are DIN and ISO standards for dynamic fork fatigue. The fork is mounted in a test fixture. The steerer is held in a fixed position with a full headset. A loading attachment is clamped in the dropouts. The ISO test requires a load of 99 lbf to be applied for at least 50,000 cycles at a maxmimum frequency of 25 Hz. The DIN test requires a load of 68 lbf to be applied for at least 100,000 cycles. For reference, the Heron fork was tested by Specialized with a load of 99 lbf over 250,000 cycles without failure.
Todd Kuzma
Heron Bicycles
LaSalle, IL 815-223-1776
http://www.heronbicycles.com