Broken spokes
- Thread starter bazzapage
- Start date
StormTrooper2
Member
I've broken three spokes on the rear of my 2016 Turbo X. Each time the heads popped off (i.e. at the hub). One and Two were random "no reason" failures. Third time happened yesterday. I'm pretty sure this was due to a stick flipping up into the wheel (there's a bend in the broken spoke). I sense the original spokes break at weak points (the spoke heads on many). The 13G (2.3mm) spoke is strong. Tension is high. Lowering tire pressure to 50 psi seems to have helped. After two breaks for no apparent reason the lower pressure seems to have cured the odd random breaking. Still, it seems the weak points in the original 13G spokes are the heads and threads - relative to the greater stiffness and strength of the 13G spoke body. The wheel was rebuilt under warranty (that's what I was told, anyway).
I'm going to try something different this time. I just ordered 40 Sapim Strong 13-14G Butted 205mm spokes (black spokes and nipples). When removing the broken spoke I noticed the threads are 2.0mm (standard). The working hypothesis for the Sapim Strong is the 13G ends provide strength while the narrower 14G mid-portion of the spokes should give a bit, reducing the instantaneous loads on the spoke heads. I ordered the spokes from GRIN Technologies. They also sell Sapim Leader 13G non-butted with 14G (2.0mm) threaded ends. I found it interesting that GRIN actually discourages buying the Leader spokes because the spoke nipples are standard size and become a weak point - recommending the Sapim Strong 13-14G instead. Interesting how the 13-14G is named "Strong". Might be better to describe them as "resilient"... oh well, if they don't break they must be "strong".
I'm going to try something different this time. I just ordered 40 Sapim Strong 13-14G Butted 205mm spokes (black spokes and nipples). When removing the broken spoke I noticed the threads are 2.0mm (standard). The working hypothesis for the Sapim Strong is the 13G ends provide strength while the narrower 14G mid-portion of the spokes should give a bit, reducing the instantaneous loads on the spoke heads. I ordered the spokes from GRIN Technologies. They also sell Sapim Leader 13G non-butted with 14G (2.0mm) threaded ends. I found it interesting that GRIN actually discourages buying the Leader spokes because the spoke nipples are standard size and become a weak point - recommending the Sapim Strong 13-14G instead. Interesting how the 13-14G is named "Strong". Might be better to describe them as "resilient"... oh well, if they don't break they must be "strong".
flymeaway
Well-Known Member
My 1st ebike was a 2014 BH Emotion Carbon. I had issues with broken spokes at the hub constantly. I spent too many hours repairing broken spokes, I moved on to building mid-drives bikes using Stan's notube rims and Rohloff 500/14 IGH with Sapim spokes and haven't broken a spoke in 4 years.
Cheers...Court J.
Cheers...Court J.
StormTrooper2
Member
I have considered that mid-drive is the answer. Lots of advantages. However, I do much prefer the quiet ride of the hub motor. All mid-drives make noise to greater or lesser degrees. I ride the W&OD trail to work so I don't need the mechanical advantage of running the power through the gears - but obviously hill-climbing is a big advantage of mid-drives. I will give these spokes a go and see if they do any better. If not I'll order the original spokes to put it back to stock and sell it on (which will happen anyway as we are moving overseas).
