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Tour Easy: Cracked Fork Autopsy

A look inside the cracked fork lug from my Tour Easy shows that it really did fracture at the top of the fork blade:

Tour Easy - cracked fork - interior flash

Tour Easy – cracked fork – interior flash

Minus the flash, plus contrast enhancement:

Tour Easy - cracked fork - interior

Tour Easy – cracked fork – interior

Looks rather grotendous in there, doesn’t it? Yeah, show me the interior of your fork…

The front is at the top, blade on the left and crown on the right. The little shiny rectangle at 1 o’clock on the crown was probably the last fragment holding the blade in place.

Finished!

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  1. #1 by Brent Crosby on 2015-05-25 - 09:39

    Maybe the manufacturer could drop a packet of “do not eat” into them before sealing them up.

    Or you could drill a hole and alosh some POR 15 in there.

  2. #2 by Red County Pete on 2015-05-25 - 11:15

    Hmm, looking at the picture, it doesn’t seem that corrosion had a lot to do with the problem, but the different stresses in a ‘bent may have contributed. I’d start mulling over a BMX fork retrofit if I still did such stuff…

    • #3 by Ed on 2015-05-25 - 13:26

      I flat-out don’t know why the interior is so rusted, although I’m sure diurnal pumping has something to do with it: hot in the sun, cold overnight, humid air goes in through the vent holes and never comes out.

      There didn’t seem to be a obvious stress riser anywhere on the chrome exterior, so I’ll write it off to an interior flaw stressed by plenty of hard use. A few dozen miles of babyhead ballast on an unopened trail along the Lehigh River probably got it started; that should count as bike abuse…

      • #4 by Red County Pete on 2015-05-25 - 17:29

        I never broke a spoke in my riding days, though the almost-total failure of my Cannondale’s rear wheel more than made up for it. I trued the wheel as best as I could, limped home from work, and built a new wheel. Didn’t use it much, since road bikes and my spine don’t mix well. When I did wheels for the Rockhopper, it was Phil hubs and some righteous rims. I still have the Park tools–might play with HPVs one of these years…

        obvious stress riser

        I’d guess the gap between the top of the fork blade and the crown would count as a riser, thus the BMX musing. Maybe some WD-40 or similar in the fork vent holes would help a smidge. One of the few places where the purists would say WD-40 is appropriate. [grin]

        • #5 by Ed on 2015-05-25 - 18:31

          Turn the bike upside-down, hose the fork blade interiors with WD-40, fast-forward a decade, and see how it works out. Sounds like a plan to me!