-
spokes fail through a process of fatigue. Low tension may be a contributing. Factor. Most spokes these days fit hub flanges well so movement is not the issue.
Loading the wheel causes spoke tension to vary that results in length changes and that the process of cyclic fatigue caused by loading. This is prime reason for fatigue failures as its cumalitive. Low tension matters if the spokes can load when ridden, if they dont unload because the wheel is stiff enough to prevent that then low tension is not a problem unless it leads the wheel to be instable.
One big reason for spoke failure is lack of stressing by the builder. The spokes need repeated grasping or stretching to fully bed them into the hub flange and stretch them. I can pull the wheel out of dish doing this. Then i turn it round and repeat and pull it back again. Tension drops of 300N are possible but normally this is done not just at the end but throughout the building process. That way when doing the final true before sideloading the rim you not having to do massive correction in dish, truness and getting the tensions back up to where they should.
You are reading a single comment by @thecycleclcinic and its replies.
Click here to read the full conversation.
thecycleclcinic
Only because I read the Schraner book recently and found what he says about spoke breakage really interesting, where are yours breaking?
If you haven’t read the book, he says (iirc) that spokes don’t break purely because of load, they break because of lack of tension or because they are moving in the hub flange and getting stressed.
He recommends replacing a broken spoke once and increasing the tension on the whole wheel. If another one breaks, rebuild the wheel with washers under the spoke heads.