I had an LBS build a wheel with a Flo 30 rim and a PowerTap G3 hub. 24 CX-Ray spokes, 2 cross. Got it back early this week and threw rim tape, tube and tire on it. Took it out for its first ride this morning, and within just a few miles I was hearing some noise in the rear. Stopped to have a look, and it was already loosening to the point where there were NDS spokes with no tension at all. I dropped it back off at the LBS this afternoon. On the way home, I realized that when I originally picked it up, they had never put a tire/tube on it, because it still had no rim tape.
I don’t know what spoke tension they used because I didn’t ask, but the wheelbuilder told me he had contacted Flo for info. I wasn’t able to ask today because he wasn’t there. I’m guessing whatever tension Flo recommended was for inflated tire, and they tensioned it rim only.
In the Flo forums, John or Chris mention that DS spokes should in general be in the range of 110 - 130kgf; NDS 50 - 100kgf, greater precision depends on spoke count, pattern and hub. I don’t know if this is with inflated tire or not.
I’m asking here if anyone knows the right tension in either state since the shop may work on it tomorrow and I won’t be able to contact Flo in time. I’m at about 175 #s.
Most tensions quoted will be for rim only. Specifics depend on the hub (flange spacing), spoke gage, and number.
I suspect the wheel was never given final tension before you picked it up.
Yeah, I’ve been investigating since I posted, and haven’t found anyone that disagrees. I asked a bunch of guys I ride with who they would trust to build a wheel, and this shop was it; but I’m wondering if he bothered to do any stress relieving.
Interestingly, Jobst Brandt and Leonard Zinn among others state inflated tire definitely reduces tension, Sheldon Brown and a bunch of others say no affect. If the wheel is properly de-stressed, shouldn’t be an issue, except Stans 340 rims which are notorious for loosening up. The complete Flo 30 front wheel I bought at the same time is just fine so far.
The correct tension is based on the spokes being used and their placement (non-DS vs DS/front) and of course the non-drive side should always have the least tension. The only way the rim comes into the equation is whether or not it’s strong enough to withstand the proper tension w/o cracking at the spoke holes. I use a Park tensionometer and check their online reference for the particular spokes I’m using (go to park.com to look up the CX-Rays.) I then double check that against the rim’s spec. If the rime can’t handle the correct tension, then you should use a different (thicker) spoke that requires less tension.
Most tensions quoted will be for rim only. Specifics depend on the hub (flange spacing), spoke gage, and number.
I suspect the wheel was never given final tension before you picked it up.
^^^^^This.
Inflation had nothing to do with it; they probably just forgot to destress the spokes (esp. with 2X). If it’s a good shop the wheel should be fine once they adjust the tension.
Well I picked up the wheel yesterday, he had retensioned it. Most of the CX-Rays on the drive side are twisted, some as much as 60 degrees. Couldn’t believe it, but the shop was crowded and I really didn’t want them to eff with it anymore, so I’ll try to rotate spoke and nipple together to straighten them out myself.
Untwisting the spokes can reduce tension, so be careful. This is a really strange case; most wrenches I know take extreme pride in wheel building. Not only is it an art, but the results of their craftsmanship are on display for quite a while. People will laud well built wheels far more than a well adjusted headset.
Well I picked up the wheel yesterday, he had retensioned it. Most of the CX-Rays on the drive side are twisted, some as much as 60 degrees. Couldn’t believe it, but the shop was crowded and I really didn’t want them to eff with it anymore, so I’ll try to rotate spoke and nipple together to straighten them out myself.
Brian
Don’t. Take it back. Ask for a manager/owner. Ask to have their best wrench work on your wheel.
Well I picked up the wheel yesterday, he had retensioned it. Most of the CX-Rays on the drive side are twisted, some as much as 60 degrees. Couldn’t believe it, but the shop was crowded and I really didn’t want them to eff with it anymore, so I’ll try to rotate spoke and nipple together to straighten them out myself.
Brian
Sounds like amateur hour in their workshop. I’m not sure how you gain any confidence in their work if you take it back. Frustrating situation.
Keep us posted on how this goes. It sounds like the LBS rushed the job a little. How much did he charge for the labor?
Finished my Christmas shopping earlier this afternoon so I had some time to work on the wheel. I set it up in a cheapo truing stand to get a reference, then carefully rotated spoke and nipple together until they were aligned correctly. In the end, I adjusted 20 out of the 24, and a couple were off by *more *than 60 degrees. It seems like there was very little movement of the rim afterwards, not enough to worry about until I get a chance to ride it.
To answer all the questions:
I paid $40 in labor
They had it for a week the first time, so they shouldn’t have been rushed in the first build. I suspect they used one of those cheap Park tension meters, which aren’t very accurate, thus it loosened
They turned around the rebuild in 2 days, while being very busy with holiday shoppers, so he probably was very rushed when he did it, but to let a wheel out of the shop with misaligned aero spokes is inexcusable
There is only one bike mechanic there, it is also a ski shop; however, folks in the area did recommend him
Won’t get a chance to ride now until Friday or Saturday, fingers crossed
Bit late here, but wanted to affirm what others had said. Twisted spokes ain’t a good sign, but twisted bladed spokes is worse, it is a sign of a bad/lazy/incompetent builder. There is a visual indicator readily available to the builder, no guesswork involved, to miss it is a sin.