Spoke tension loss
I’ve had loose spokes before and sorted them out without issues. However I lost a spoke on a last ride. Wheel was straight and true previously as I had just checked the tension.Posted 6 months ago
However I finished ride after the spoke went and the rest were OK when I spotted the loose spoke. By the time I had got to the car (about 2 miles) there were 5 where the nipples had basically unwound. I’ve never seen anything like this before and am curious as to why.
Only thing I can think of is its a 28h rim and the loss of tension is catastrophic?
Below a threshold then the spokes go slack each time they reach the bottom of the wheel or get unloaded in a corner, landing, bump etc. Once they’re slack there’s no friction on the threads to stop them unwinding.
It’s a PITA with rims with low spoke tensions (stans and other light rims that do without eyelets).
Solutions are to use thinner spokes which stretch more, therefore the wheel has to deflect more before they are slack (particularly on the non drive side at the rear where the stans maximum tension on the drive side basicly leaves the other side slack). Or just use some sort of threadlock on the thread (makes re-truing harder, but since doing it I’ve not had to so 6 vs 1/2doz).
If you go down the threadlock route, you’ll need to soak the nipples in petrol or similar to remove any trace of grease used in the original build.Posted 6 months ago
I’d expect the tension wasn’t high enough.Posted 6 months ago
Possibly but I took a reference tension when it was first built as my tension gauge isn’t calibrated. It was basically the same after the spoke replacementPosted 6 months ago
Did you check the tension with the tyre beaded? Some tyre/rims combos suffer from a large tension drop when tubeless tyres bead. If the low tension side was already borderline its not uncommon for them to go slack when the tyre is fitted.Posted 6 months ago
Yup that appears to be it. Spoke tension appears that it was low on the non drive side from new. I’ve re tensioned the wheel according to the roval instructions and the spoke tension is significantly higher but more like I would expect a wheel to be.
Will see how it is after a ride this afternoonPosted 5 months ago
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