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Old 02-20-06, 12:23 PM   #1
simplify
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spoke tension making rim bulge around eyelet? Did I overdo it?

I'm trying to tension my spokes as well as possible, following the advice in Jobst's book and Schraner's too, and what I've read here on the forum. High tension, but not overtensioned. I noticed that the rims are bulging slightly around the eyelets on the Drive side rear wheel spokes only, so please tell me if I've overdone it and hurt these rims. They are mid-80's vintage Araya rims, polished aluminum, double walled with double eyelets. The spokes are straight-gauge 2.0mm stainless. I hope you can see the bulge at the base of the eyelets in the attached photos, it's difficult to capture it. I don't see any signs of stress fractures in the rim yet, so should I just de-tension them a bit and see what happens? Or are the rims structurally compromised now?

Maybe I need to find a hobby that's less frustrating, like maybe hitting myself repeatedly in the head with a hammer. At least I wouldn't do so much damage.
Attached Images
File Type: jpg rimbulge1.jpg (27.7 KB, 16 views)
File Type: jpg rimbulge2.jpg (30.6 KB, 23 views)
File Type: jpg rimbulge3.jpg (20.0 KB, 18 views)
File Type: jpg rimbulge4.jpg (30.0 KB, 12 views)
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Old 02-20-06, 12:27 PM   #2
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it's not unusual, you may notice on dark anodized rims with brake wear will often have a light-dark pattern that corresponds with the spoke holes.
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Old 02-20-06, 12:44 PM   #3
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right, these have that "broken line" look on the sidewalls too, which they've always had. But the concern I have is that bulge right at the eyelet, right at the base of the spoke, on the formerly-flat surface right where the eyelet is. I think you can see it best in the second and third photos.

Last edited by simplify; 02-20-06 at 03:20 PM.
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Old 02-20-06, 06:48 PM   #4
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Old 02-20-06, 09:00 PM   #5
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Right, I get it. But #1, I don't have any idea what the manufacturer's suggested tension is for this vintage rim--do you?? And #2, serious cash flow issues at the moment which prevent an outlay of $60 for this instrument. It's on my wish list, but Christmas is a looooong way off. Can someone please just tell me if the structure of the rim appears compromised?
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Old 02-20-06, 11:31 PM   #6
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Quote:
Originally Posted by lawkd
Right, I get it. But #1, I don't have any idea what the manufacturer's suggested tension is for this vintage rim--do you?? And #2, serious cash flow issues at the moment which prevent an outlay of $60 for this instrument. It's on my wish list, but Christmas is a looooong way off. Can someone please just tell me if the structure of the rim appears compromised?
nah...just cosmetic. don't worry about it. you'll forget and no one will notice it
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Old 02-21-06, 07:13 AM   #7
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I'm not sure about this, but it might not hurt dropping your spoke tension by half-a-turn all around. But as I said, I don't have expertise in this area. Hopefully you'll get some more knowledgable people answering your question.
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Old 02-21-06, 10:26 AM   #8
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If the 'bulge' deformed the rim enough to cause a hop, then yes, you have yielded the aluminum and have over-tensioned the spoke. Not much to be done now but ride the wheel. If you loosen the spoke you will cause more problems when you re-tension it since the Aluminum has already yielded.

Enjoy
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Old 02-21-06, 11:19 AM   #9
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No, no hop or deformity of roundness at all. It's nice and round and true. Just the slight raising of the flat part around the eyelet, that's all that seems amiss. The sidewalls of the rim are not deformed at all. They've always had a slight "broken line" appearance in the brake track, but there's no perceptible irregularity, either visually or by feel when braking.
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Old 02-21-06, 03:42 PM   #10
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Quote:
Originally Posted by lawkd
No, no hop or deformity of roundness at all. It's nice and round and true. Just the slight raising of the flat part around the eyelet, that's all that seems amiss. The sidewalls of the rim are not deformed at all. They've always had a slight "broken line" appearance in the brake track, but there's no perceptible irregularity, either visually or by feel when braking.
its just cosmetic, but i am not saying you shouldn't loosen them and re-do the tension. just because its cosmetic doesn't mean you should leave it too tight if they are.
look at this conversion table:

http://www.parktool.com/products/doc...05912_4301.pdf

it might help you. you seem smart so my idea is that you can sort of extrapolate some useful info from it even though it is meant to be used with their tensiometer. i am thinking if you find your spoke size you can kind of compare it to other sizes and maybe get a feel for what end of the spectrum you fall. i don't know, just trying to help
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Old 02-21-06, 03:57 PM   #11
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Hey thanks! That really does help, I hadn't seen that table before, and didn't realize there was such a big difference in tension readings for different gauges. I agree, about bringing the tension down a tad, and I am definitely going to get that tensiometer as soon as I can afford it. Thank you all for your help.

Last edited by simplify; 02-21-06 at 04:04 PM.
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