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Help! Over-tightened spokes on KH20FL rim

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  • Help! Over-tightened spokes on KH20FL rim

    Like an idiot I went around my wheel, starting from the valve stem, and tightened each spoke one full turn - way too much! Now one or two spokes near the valve stem have pulled their eyelets partly out of the rim. The problem before was that the looseness of my spokes was leading to one of them snapping every few weeks, but this new problem is obviously more serious.

    Is it possible to repair this? Should I go around and loosen all spokes 1/2 turn? Right now, my uni is fully rideable, and my wheel seems fairly true, but I thought I'd check here and see what people say before I go on another ride.
    Attached Files

  • #2
    Yikes! I haven't seen that happen before, but I'd hesitate to ride it like that out of fear of doing further damage. I think I'd pull the tire and have a look from inside, see if there's any damage to the actual rim extrusion and what the chances were of pushing the eyelet back and re-peening it.

    That being said, riding on N-1 spokes where N is fairly large is usually ok if suboptimal.

    Tough break, good luck with it!

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    • #3
      Originally posted by song View Post
      Like an idiot I went around my wheel, starting from the valve stem, and tightened each spoke one full turn - way too much! Now one or two spokes near the valve stem have pulled their eyelets partly out of the rim. The problem before was that the looseness of my spokes was leading to one of them snapping every few weeks, but this new problem is obviously more serious.

      Is it possible to repair this? Should I go around and loosen all spokes 1/2 turn? Right now, my uni is fully rideable, and my wheel seems fairly true, but I thought I'd check here and see what people say before I go on another ride.
      First:
      For the benefit of anyone else who wants to tension their wheel, never tension by turning adjacent spokes sequentially around the wheel. When you start with loose spokes you can snug them up to the same number of turns, or by using a nipple driver to the same level relative to the end of the spoke. After that you want to develop the tension around the wheel. I use the 3x3 method which means that you turn the first nippe next to the valve stem, count three spokes (fourth spoke from valve), turn that the same amount, and continue around the wheel untiil you get to the valve stem. For the next round you will start with the second nipple from the valve stem. For the third round you will start with the third nipple from the stem. After three rounds you will have tightened all of the nipples by the same amount, and you will have brought up the tension evenly. I would do it in small increments, like quarter or half turns. You may have to do multiple sets of three rounds before you get up to tension, but it is far better than over stressing the rim.

      Second:

      If someone brought me a wheel with the backstory you have provided I would start by detensioning the wheel to get it back to a known state. I would inspect carefully any eyelets that were suspect, and in the case of the one shown I might use a rim washer to relieve the stress off of the eyelet. Then I would snug up the spokes with my nipple driver paying attention to any spokes that have a washer since the tension will be off by the thickness of the washer (about a half mm). Once the wheel is even, but loose I would proceed with the 3x3 tensioning until the wheel has tension, but not at final tension. Then I would true it, and follow that with 3x3 up to final tension. After that it shouldn't need much final truing. Of course there would be stress relieving, and setting nipples, spoke heads, and such. On a job like this there usually isn't much problem with the set of the spokes since it was already a built wheel.

      Good Luck with it.

      Jerry
      "A properly ridden unicycle is like an object in orbit: constantly falling but never landing." -Diogenes

      Comment


      • #4
        Listen to jtrops. He knows what he is talking about
        Last edited by kahunacohen; 2015-10-25, 12:43 PM.
        KH20 Street, 110/127 Moments with rollos
        Stock KH27.5 with Black Street Saddle
        Oracle 36/Oregon Hub, 127/150 spirit

        Comment


        • #5
          Originally posted by LargeEddie View Post
          I think I'd pull the tire and have a look from inside, see if there's any damage to the actual rim extrusion and what the chances were of pushing the eyelet back and re-peening it.
          Yeah, I took the tire off right away. There doesn't seem to be any damage to anything other than the eyelet itself. I would consider buying a new rim at this point, but KH20FL is no longer sold.

          Originally posted by kahunacohen View Post
          Listen to jtrops. He knows what he is talking about
          Yes, he has helped out tons of people on this forum, including me more than once. I'm going to do exactly what he said above, though I am a little surprised that it's not possible to just replace these eyelets rather than messing around with washers and whatnot.

          Comment


          • #6
            Originally posted by song View Post
            Yeah, I took the tire off right away. There doesn't seem to be any damage to anything other than the eyelet itself. I would consider buying a new rim at this point, but KH20FL is no longer sold.

            Yes, he has helped out tons of people on this forum, including me more than once. I'm going to do exactly what he said above, though I am a little surprised that it's not possible to just replace these eyelets rather than messing around with washers and whatnot.
            rim washers were the norm before eyelets, even going back to wooden rims. You might be able to find something suitable in the rivet section of a good hardware store, but you would want to match the inside, and outside diameter pretty closely. All things being equal a rim washer is a much easier solution. I would probably keep the original eyelet as well just to keep the nipple centered in the hole.
            "A properly ridden unicycle is like an object in orbit: constantly falling but never landing." -Diogenes

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            • #7
              Yeah jtrops was super supportive when I was learning to build wheels. It's why I love this community. Good luck with the rim. Let us know how it works out.
              KH20 Street, 110/127 Moments with rollos
              Stock KH27.5 with Black Street Saddle
              Oracle 36/Oregon Hub, 127/150 spirit

              Comment


              • #8
                Originally posted by jtrops View Post
                the 3x3 method
                That's a really handy tip, thanks!
                Unicycling is the fountain of youth.

                Comment


                • #9
                  Originally posted by jtrops View Post
                  rim washers were the norm before eyelets, even going back to wooden rims. You might be able to find something suitable in the rivet section of a good hardware store
                  Saying that those eyelets can be replaced with rivets is not quite right- they ARE rivets!! 4mm rivets, to be exact. I found a bag of 100 of them today at Home Depot. They were made of shitty metal, and the pliers they came with do not open wide enough to clamp them into my rim, but I managed to install one anyway by gently tapping a conical metal rod into it to widen it, then snapping it into my rim with my fingertips. After that, I reached inside the rim with a countersink and flattened out the bit of rivet that jutted out of its hole so that it would stay in place.

                  Funny you mention wooden rims- after a lot of legwork, I finally found a bike shop where someone had heard of rim washers. He had a bunch lying around... because he had recently built a wooden rim!

                  Anyway, as you predicted, this repair will be easier and probably better with rim washers, so that's what I'll use, but I wanted to put the info out there in case anyone else encounters this problem. Good 4mm stainless steel rivets are the eyelets in seemingly any KH or (I think) Nimbus rim. Not even Josh at UDC was able to tell me that, though. Many bike store personnel said I should just throw away my rim, even though it is undamaged.

                  In the photo, the middle rivet is from Home Depot. It is backed up by a rim washer, so its purpose is mostly cosmetic, but, as you said, it does keep the spoke centered. With the right rivets and a large enough crimping tool, eyelets should be 100% replaceable without even resorting to washers.
                  Attached Files

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                  • #10
                    I'm glad it's working out. My only point about the rivets was that a good hardware store may have suitable ones.

                    Most shops wouldn't attempt a repair that involved replacing a rivet, and for that matter they would probably steer clear of reusing a rim that had a pulled rivet. As long as the rim is not modified the manufacturer takes the lions share of responsibility for the part. In this case any further damage due to unknown cracks wouldn't be catastrophic and would most likely happen due to a significant trauma. So, i would feel safe using a washer.

                    Honestly, i think washers do a better job than eyelets, but it adds more time to building, and machines can't build with washers. I would bet that's the real reason eyelets became standard as rims got lighter.
                    "A properly ridden unicycle is like an object in orbit: constantly falling but never landing." -Diogenes

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