collected by Damon Rinard
Gathered as I come across
Please let me know if you can help me get any test standards I'm missing. Thanks!
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International Standards Organization http://www.iso.ch/ . Bicycles fall under 43.150 Cycles. Last I checked (2000) the test methods standard "ISO 4210:1996 Cycles -- Safety requirements for bicycles" cost roughly $80 US.
Easton forks. John Harrington, quoted in Bicycle Retailer & Industry News Interbike Show Daily, Days 3 & 4, September 2000, p. 24: "Easton's new all-carbon fiber fork [...] can go 200,000 cycles with 170 pounds without failure. Most of the other forks on the market fail between 50,000 and 100,000 cycles with 130 pounds."
Old DIN standard. Marten Gerritsen <firstname.lastname@example.org>, quoted from Framebuilder's e-mail list November 2000:
"Two things to worry about: impact strength and fatigue strength.
Rough testing impact strength isn't too difficult. The old DIN standard called for dropping a 50 lbs weight from a height of 6" on a bogus hub fixed to a horizontal mounted fork (amazing how these original metric dimensions convert back to pounds and inches!). Suspending an old weighted down bike with two ropes from the ceiling and slamming it into the wall from a controlled height is another pleasant way of spending an afternoon and gaining insight (don't forget the beers for post-analysis of the results).
Fatigue strength is a bit more difficult and takes time (and dentures if you're very unlucky) but probably not much of a real concern: roadbikes with 120 psi tyres are IMHO a more endangered species, and even on those forks the brazing area of both legs has about 3 times the area of the steerer at the notch at the crownrace. And remember those old Raleigh roadsters with tubular chrome capped crowns. I don't think they had much of a fillet to keep the forklegs in place."
Columbus forks. From http://www.framebuilding.com/carbon forks.htm .
Columbus carbon forks are produced in accordance with ISO 9000. All forks are marked and their history can be traced. The tests include destruction testing and are performed on finished product samples. They are very severe:
- Frontal and side strength test:
A load of 200 N is first applied to the frontal part and then to the side part of the fork. The flex is measured on each occasion and this must not exceed a set value.
- Shock Test:
A mass of 225 N is dropped from a height of 180 mm on a properly restrained fork. In order to pass the test the fork must resist without breakage or residual deformation.
- Static Test:
A load of 200 N is applied to the frontal part for 1 minute. In order to pass the test the fork must resist without breakage or deformation.
- Fatigue Test:
During this test an alternate force of +-800 N is applied. In order to pass this test the fork must resist for 300,000 cycles (500,000 cycles for Muscle) without breaking.
Din 79100, (old version). Marten Gerritsen <email@example.com>, quoted from Bicycle Science e-mail list October 2000:
- Static: vertical force of 600 N @ 50 mm from end for 60 secs, repeat other side. No plastic deformation should occur.
- Impact: drop a 10 mass from 500 mm on end-50 mm. No breakage or visible tears.
- Dynamic: +/- 190 N (10E5 cycles) on both ends in phase, subsequently +/- 150N out phase (10E5 cycles).
"The standards in Din 79100 were considered low. See also http://www.efbe.de/ "
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Damon Rinard firstname.lastname@example.org
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