just snap all of a sudden? Of all things it was on the wall climb whilst cranking round one of those tight switch backs.

Went with a real bang and snapped at the middle of the spoke.

Wheel build is about a year old (proII/721) and had no problems with it, wasn't buckled etc…

Top guys at skyline cycles sorted it, but just wondering what might have caused it to fail. I could understand if I was jumping or something

It'll have been weakened for whatever reason. It's not only the obvious things like jumps that put stress on your wheels – when climbing, a lot of your weight is on the back wheel which is also dealing with pedalling forces etc.

I'm no wheel guru but could it have been over tensioned?

Dunno, probably just waiting to happen, or a weak spot, something like that. I think spokes are cold drawn, so the normal fatigue spots are where it's been worked, so at the bend or the thread, but it doesn't stop them from just "going" once in a while

my wheels are currently away for warrenty because ive had 5 or 6 spokes snap in the middle of spokes as you describe.

factory wheels ! – ive built wheels for 10 years for a shop downhill/xc/road/lightweight and never had this issue – so i lodged a complaint and they took em back to rebuild em.

Snapping in the middle is unusual – it's likely to have either been damaged at some point (stick/rock type thing) or just a manufacturing defect.

Possible impact damage in the past?

most likely your missus cut it, thinking it was a brake pipe.

call the police and have her charged with attempted murder.

I had a spoke break near the top of Kipps at GT last month. That was annoying in that it was the worst place/time for it to happen on that ride but would have been much worse had it happened similarly on my next planned ride which was Mount Keen. I have been advised that once a spoke breaks the wheel strength is fatally compromised and a rebuild with a new rim is needed. I'm being a bit cautious until I get that sorted.

Kunstler – Member
I have been advised that once a spoke breaks the wheel strength is fatally compromised and a rebuild with a new rim is needed.

That's utter BS! You can often keep riding on a wheel missing a spoke, and usually they repair up fine (depending on damage obviously).

depends on the wheel cynic al

if it was a stock wheel that came on a factory bike with cheap spokes – and was snapping from fatigue at shoulders id reccomend replacement – often youd find your self chasing broken spokes round a wheel !

well built wheels with dts dont generally do this

I have been advised that once a spoke breaks the wheel strength is fatally compromised and a rebuild with a new rim is needed.

Really? I need to get the wheels on all four of my bikes rebuilt pronto then, i've obviously been on borrowed time all these years! 😉

Sure – after 3 spokes go for no apparent reaons I's say rebuild – the post refers to one spoke though.

I just take spoke breakage as an act of god. Given the abuse wheels take I'm surprised they don't fall to bits in hours. With a disc braked wheel you can still ride with several broken spokes, there's plenty of redundancy – I'd just replace any broken ones ASAP. Having said that, I can't remember the last time I broke a spoke…

one large cause of spoke breakage is uneven tension between spokes

trail_rat – that sounds very much like my situation. It's an xtc which has everything else upgraded but the original wheel is four years old. Several spokes have been replaced now – two more broke during the last replacement.

Wasn't a factory set – LBS build, I think most likely is that it could have been weakened as suggested. Very odd though first time I've had a spoke go in all the years I've been riding.

I actually continued riding w2 and got skyline to fix it afterwards. I didn't die, but the wheel most definitely was buckled by the end of the ride it did true up fine.

Irritatingly the nipple is inside the rim now rattling around.

"With a disc braked wheel you can still ride with several broken spokes, there's plenty of redundancy "

I do not think that is really a good idea, rim braked wheel maybe with extreme caution,
all the braking force in a disc wheel is via the spokes…

The odd spoke may break, if your wheel breaks 3 or more spokes best rebuild it unless you have a good idea why its happening.

I do not think that is really a good idea, rim braked wheel maybe with extreme caution,
all the braking force in a disc wheel is via the spokes…

can i suggest you think about that statement.

yep, thought about it , the braking force is the hub being stopped by the disk. Hub needs to transmit braking force to tyre via rim and spokes.

Rim brake – force from rim to tyre .

Is there some other explanation ?

Spokes are involved in dealing with the stresses of rim braking.

yep, thought about it , the braking force is the hub being stopped by the disk. Hub needs to transmit braking force to tyre via rim and spokes.

Rim brake – force from rim to tyre .

for the love of god your not an engineer – please say your not !

why not explain if what I said was so wrong?

yes spokes are involved in the stresses of rim braking , but I think they are far more important in disc wheels

suppose you build a radially laced front wheel with a disc hub and rim brake rim.

what brake would you feel safest with that wheel ?

what your implying is that the hub would continue to rotate irrespective of rim slowing down.

all a rim is , is a giant disk …

all the braking force in a disc wheel is via the spokes…

We're just being pedantic about that statement, I suppose the answer is that with a rim brake there are no rotating* forces on the spokes.

*yeah sounds wrong but YKWIM

i thought stw existed solely to be pedantic and pick up on minor points ….

i see where your coming from – it is a less force going back to hub but its a force none the less

simple fact of the matter is – rim brakes are not really possible with a snapped spoke due to wonky rim – disk brakes are due to redundant contingency of spokes in 32/36 spokes

yes ok i get your point with a rim braked wheel , the braking spokes stop the hub , but do you see my point? the torque issues with disc hubs ?

yep – dont worry i was just being pedantic 😉

ok ok I think we are on a similar track , I forgot about the wonky rim redundancy ,

All friends in the end! 😀