hi all,

today i found my fourth snapped spoke in just over a month!

the spokes all seem tight as i regularly check them, and its only needed minor tweaking since i got the wheel new from superstar about a year ago

its the rear wheel, the rim is a Superstar am490, the hub is a superstar switch evo

is it because they are the cheapo silver SAPIM spokes, and not double butted? the spokes have all snapped in the same place – where they enter the nipple.

any ideas / suggestions? thanks

happened to me in the alps ,broke 12 in 3 days !

Most spoke failures are from fatigue, which is usually caused by inadequate tension. DB spokes can help, but getting them tight enough is the key.

Also, double check that the nipple is free to align itself with the spoke – if the hole is too tight, you get a bend where the spoke enters the nipple – not good.

Not the spokes, just a damaged wheel or most likely, a poor build.

Best solution is to have it re-built with new spokes. Or you’ll just end up with the same problem.

If the rim has canted nipple beds, the builder should ensure they lean the right way. Also that the nipples are correctly formed, i.e. a nice radius on the seat.

Based on numerous previous threads, there may be (9 letter) clue word somewhere in your post ..

“all seem tight as i regularly check them, and its only needed minor tweaking”
They may all be tight, but are they all equally tight?

Seized nipples?

Rebuild required anyway.

I’ve snapped 3 spokes in my life. I weigh far more than you do and ride far more clumsily. I never tweak.

Make of that what you will.

Best solution is to have it re-built with new spokes. Or you’ll just end up with the same problem.

This. Once one has reached its fatigue limit, the others aren’t far off, so all the spokes will snap sooner or later.

thanks

will get it rebuilt with new spokes

I had a Syncros/Hope rear wheel which snapped spokes pretty much every time I rode on it. My LBS thought it was just too worn and fatigued, I guess it just reached the end of its life.

I had multiple failures touring on an Alfine. I’m told it was due to the spoke diameter being too small for the spoke hole diameter of the hub, causing vibration, leading to failure. How big are your flange holes?

cheapo silver SAPIM spokes

Sapim don’t make sh!te spokes.

most probable issue is an imbalance in spoke tensions – uneven tension between spokes causes failures and is self perpetuating.

This is not just that spokes are ‘tight’ but the same tightness as the others on each side of the wheel.

Get it rebuilt with new spokes by someone who knows how to build decent wheel.

I’m told it was due to the spoke diameter being too small for the spoke hole diameter of the hub, causing vibration, leading to failure

That’s not quite right – what happens with spokes that are too small for the hub flange is that, instead of the spoke elbow bedding into the flange, the elbow is clear of the flange and the tension is taken on the head directly. This means the spoke can flex slightly at the elbow, causing it to fatigue and snap. The solution is spoke washers – little brass washers under the head of the spoke, pulling the elbow into the correct position against the flange.

*sniggers*

He was asked how big his flange hole was.