Originally Posted by
Olaf330
So for the third time this month, I've snapped a rear spoke. It's always the spoke connected at the drive side, right at the spoke head bend. The rims are Alexrims ID19, 32 hole.
I've had the spokes replaced for free where the bike was purchased at Performance Bike. They mentioned after the third one they'll look into a warranty replacement. They feel it may be a defective rim or hub. I dunno.
The wheel was assembled sub-optimally. The parts should be good enough.
Spokes fail due to fatigue when the wheel was not properly stress relieved thus leaving high-stress regions near the elastic limit in the elbows from when they were manufactured. Low tension can also reduce the number of stress cycles a wheel will survive.
A replacement wheel built the same way will have the same problems. One which has sufficient uniform tension and is stress-relieved (and not starting with fatigued spokes) will not.
You get to sufficient tension by increasing it until the wheel deforms in waves when you stress-relieve after which you back-off half a turn and re-true. You can use a tension gauge. You can go for the right musical pitch.
You stress relieve by wearing a pair of work gloves and squeezing near-parallel pairs of spokes as hard as you can (except with very light or radially-laced rims). You can put an old left crank or brass drift in the spokes where they cross and twist them around each other.
Or you can delegate all this to a competent wheel builder.