Bike Forums

Bike Forums (https://www.bikeforums.net/forum.php)
-   Road Cycling (https://www.bikeforums.net/road-cycling/)
-   -   Final tension adjustment is potato chipping my wheel (https://www.bikeforums.net/road-cycling/925762-final-tension-adjustment-potato-chipping-my-wheel.html)

rpenmanparker 12-11-13 10:50 AM

Final tension adjustment is potato chipping my wheel
 
I'm rebuilding a pair of wheels with the same model Kinlin XR 200 rims, just new. Actually just transferring everything to the new rim except using new nipples. I'm pretty sure I had the old rear wheel higher spoke tension side at about 120 kgf, but I can't get the new one over about 100 kgf without the wheel potato chipping. Because I am building with a 16:8 spoke design, my tensions on the two sides are nearly identical, so I don't need the 120 on the high side to have a decent tension on the low side. About 100 kgf on both sides would still be better than most builds realize on the low tension side. So some questions. Am I doing something wrong? Do I just have a weak rim? Never had this problem with XR 200s before, but I think this one is on the light side of the specification (371 g vs. nominal of 385 g). Should I just be happy with the 100 kgf and be done with it? Thanks for any help you guys can provide.

canam73 12-11-13 11:00 AM

Just to be clear (and if you re-using spokes I think it would have to be) was your old build 16:8? And if so were you at 120 kgf on both sides before?

rpenmanparker 12-11-13 11:35 AM


Originally Posted by canam73 (Post 16321027)
Just to be clear (and if you re-using spokes I think it would have to be) was your old build 16:8? And if so were you at 120 kgf on both sides before?

Yes, same lacing before. It has been a couple of years, and I don't remember exactly, but 120 kgf on the high side is my standard practice, and I don't specifically recall a problem. With this design, the low side would be about 90% of the high side.

rpenmanparker 12-11-13 02:04 PM

Well I just got the wheel finished and very true and centered at about 100 kgf on the high tension side and 90 on the low tension side. That is going to have to do as every time I try try to go up from there I lose it. Still interested in any comments from the peanut gallery however.

achoo 12-11-13 02:53 PM

What was the old rim?

3alarmer 12-11-13 02:55 PM

...you'll get better advice from a thread in mechanics, but generally speaking,
"potato chipping" as a form of deformation is the result of excessive tension.

When I build a set of rims that are of a new kind in my experience, I generally
follow Brandt's advice to go right on up tensioning until I begin to notice such
deformation, then back off everything about a half turn. If it's a new batch of
rims, for all intents it is new to you. They often come different in different
batches from the makers, including differing erd's.


Once you are at max tension in terms of deformation, or just below it, actually, you ought to be happy and quit.

rpenmanparker 12-11-13 03:16 PM


Originally Posted by achoo (Post 16321874)
What was the old rim?

All same, Kinlin XR 200. Just a different color.

rpenmanparker 12-11-13 03:20 PM


Originally Posted by 3alarmer (Post 16321879)
...you'll get better advice from a thread in mechanics, but generally speaking,
"potato chipping" as a form of deformation is the result of excessive tension.

When I build a set of rims that are of a new kind in my experience, I generally
follow Brandt's advice to go right on up tensioning until I begin to notice such
deformation, then back off everything about a half turn. If it's a new batch of
rims, for all intents it is new to you. They often come different in different
batches from the makers, including differing erd's.


Once you are at max tension in terms of deformation, or just below it, actually, you ought to be happy and quit.

Well, that's just about what I ended up doing. I just didn't remember having a problem with the same rim type previously. But as I said, these are about as light as this rim ever comes. Thst might be the reason I couldn't get to 120 kgf. Brandt's advice makes sense. No preconceived expectations. Thanks.


All times are GMT -6. The time now is 04:24 PM.


Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.