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Tour Easy: Cracked Fork!

The fairing on my Tour Easy started making unusually loud booming sounds while we were out on an errand, so when we got home I poked around the front end to see what had worked itself loose. I finally managed to produce the sound, which turned out to be due to a very small motion in the fork:

Cracked Tour Easy Fork

Cracked Tour Easy Fork

That’s after 14 years and maybe 30,000 miles, so I’d say it did pretty well, all things considered.

On an upright bike a front fork failure kills you: the broken blade rotates forward, jams into the ground, and flips you over the handlebars. I rode about 8 miles with a broken fork and nothing exciting happened.

The Tour Easy’s design dates back to the mid-1970s, when custom bike parts weren’t readily available, and the front fork seems sized for 26 inch tires. A tubular bridge welded across just over the 20 inch (37-406) tire provides a fender mount, stiffens the blades, and, in my case, acts as a second bridge. On my bike, the fork supports the polycarbonate fairing and the Phil Wood hub provides an absolutely rigid connection between the blade dropouts.

For reference, the headset uses J.I.S 1 inch dimensions, with a 27.0 mm ID crown bearing. The stack height runs around 35 mm, but I don’t know the head tube ID.

A pair of forks are on their way; I’ll replace the one on Mary’s bike before it fails…

 

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  1. #1 by geppa dee on 2015-05-11 - 08:39

    In all honesty, a flip over the handle bars is not a guaranteed kill. It happened to me when a small dog jumped on the bike path 1 meter in front of me and I happened to have a miss-adjusted front brake. Wearing a bike helmet made it so, even though I plunged head first in the asphalt, I only got a scratch or two. On a weird/funny note, the dog owner, having just witnessed the incident, asked me if I wanted a glass of water. :)

    • #2 by Ed on 2015-05-11 - 13:42

      a flip over the handle bars is not a guaranteed kill

      Granted, but a head injury generally doesn’t make you a better person.

      With a bit of luck, the brake levers & cable would hold the fork together until you got stopped. As long as you didn’t grab the front brake, that is!

  2. #3 by Brent Crosby on 2015-05-11 - 11:23

    Not going to use this as an opportunity to get TIG setup?

    • #4 by smellsofbikes on 2015-05-11 - 11:54

      Having tig welded several investment-cast lugs, I’m going to make the case it’s not likely to be worth the time taken to do it because they’ll just break somewhere else nearby. If it happened in the middle of a tube, I’d be more optimistic about its long-term survival.

      • #5 by Ed on 2015-05-11 - 13:49

        If it happened in the middle of a tube

        I’d expect a fork to bend in the middle due to a collision, after which it’s pretty much junk: once you bend it, you cannot mend it.

        In this case, I think the lug broke at the top of the fork blade tube, so there’s really not much metal inside there to weld. I should autopsy the thing to see what happened…

        • #6 by Red County Pete on 2015-05-11 - 17:05

          I think you’re right. As I recall, those are silver soldered, and that connection held. Just above the tube would be a good stress point.

          I looked into a ‘bent trike that was TIG=welded alloy tube. The fabricator had to get the frames heat-treated to normalize the steel after welding up. No idea what the custom frame makers do–it was silver solder and brazing back in the USENET days of rec.bike.

    • #7 by Ed on 2015-05-11 - 13:46

      The bigger the blob, the better the job!

      I sprayed money at this problem to make it go away. Easy Racers has forks in stock, cut to length, and with investment-cast crowns that should last even longer.