Forked Up

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Looks like a nice Reynolds 531 fork, doesn’t it?  Not!  While recently test riding one of my projects, I noted a lot of lateral flex in the front end of this 1976 Raleigh Gran Sport:

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I immediately thought that the giant bars, which are already flexible in and of themselves, were exerting forces over the front wheel, and combined with the long reach stem, gave the bike a very strange wobbly feel – somewhat akin to the handling characteristics of a mixte frame.  Certainly, this was not caused by the frame geometry itself, I was sure.

So, I installed some regular, narrower bars, but the same strange flex continued to occur.  Then, I rebuilt the headset, thinking that it was out of adjustment, and I adjusted the front hub again, even though it was also just fine.  Still, the flexible feeling continued.  Then, I disassembled the fork yet again (grrrr…) and examined it carefully.  Usually, you think of impact damage when looking at a fork.   But the blades and steerer tube were perfect.  There were no cracks or bends, and the paint and chrome showed no signs of any kind of damage.  I squeezed the fork legs together at the dropouts and found that they flexed quite a bit.  Fortunately, I had lots of other steel forks around to compare this fork to.  While all steel forks will flex when squeezed, this one REALLY flexed quite a bit more – several millimeters more by the naked eye.  I didn’t think the variation was caused by different tubing material, because I compared this fork to not only another Reynolds fork, but also to an ALAN fork, which is known to have a lot of flex.

I had previously checked the brazing at the fork crown, but now thought that I had better get my pick out and go over the brazing carefully.  Sure enough, on one fork leg, what I had thought was brazing, covered in a bit of road grime, turned out to be just…road grime.

fork braze

Brazing material is missing, tiny pinholes visible.

I prodded the area, got out my tiny flashlight and could see that this fork leg, while not on the verge of imminent failure, was not properly brazed into the fork crown.  It looks like the lug and/or fork leg were over-filed and too loose when inserted, and there was too large a gap to fill with brazing material.  Or, possibly the gap was too tight when brazed, and the leg loosened up over time, revealing the complete lack of any silver in the gap.  Below is a comparison of the two legs, the first one showing the normal looking braze.

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Brazing okay on this leg.

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Gaps in brazing on this leg.

I am thankful that I discovered this now, and thankful for my rigorous test riding standards.  And, fortunately, steel does a good job of warning the rider of a potential failure.  It’s another reminder of how important it is to not blow off any odd or unusual feel that your bike gives you.  Be careful out there!

6 thoughts on “Forked Up

  1. I had the same model, but I think it was a 1975 (white frame with light blue highlights). There was definitely a small gap in the brazing at the seat lug, and the fork’s crown race needed a coke can shim.

    • I should not be surprised by that. But it is sad that Raleigh’s quality control seemed to take a nose dive starting in the 1960’s, and certainly continuing from there. An interesting treatise on the British Cycling Industry, called “Framing Production” by Paul Rosen, gives a lot of background into what was going on at Raleigh headquarters after the merger with TI/BCC. There were other forces at work as well, all of which helped to drive down Raleigh’s once admired production values.

  2. That was some pretty astute sleuthing on your part, Nola. I’ve never run across a similar issue in all my years of riding. What’s your best guess on whether this fork can be repaired? No doubt Portland has many skilled frame builders who could weigh in on this. Without a doubt 531 forks from the same era are pretty rare. Of course a modern replacement fork is another option.

    • Hi Tom, I am really glad to have discovered the issue. But…with this bike I don’t think having a new fork built would be justified – it’s just not a rare enough machine, plus it is no longer original. One could buy a new off the shelf Tange fork that would be fairly close in length measurement to the old fork for a few hundred dollars. To repair the fork means taking it to a frame builder, where they will need to assess the problem, remove the paint in the area that needs re-brazing, fix it, then send it off to the painter and hope that they can match the color reasonably well. That might cost about half the cost of having a brand new fork custom built, using Reynolds 531 or a similar type of tubing. I also have an ALAN fork that happens to be very close in size – and I might try that if I can get the stack height lower with a different head set. A good resource for determining the effects of replacing an old fork with a new one that is not an exact match can be found here: http://sheldonbrown.com/rinard/forklengths.htm In terms of working with frame builders, I have found it best to accumulate a bunch of small jobs before bringing it to the builder, to make it financially worthwhile for them, which helps bring you up to the top of their very long backlog.

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