SPOKES

[anotherkiwi]

Because all our manufacturing went to China...

 

[johnc46]

Altering the elbow angle so that the spoke head sits flush against the hub and using a spoke washer, sorted my Aurora which was breaking rear spokes weekly, 3 years on and never a broken spoke since. I am no expert but this worked for me.

https://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwj3xfGc9dTPAhWnB8AKHQZoD_MQFggjMAA&url=http://www.wheelfanatyk.com/blog/wheel-building-tip-no-8-know-your-spoke-elbows/&usg=AFQjCNEgSBdG-5zYAR6KmNgyvT0YJahn3g

 

[trex]

good read. I particularly like his article on becoming a wheel whisperer:

http://www.wheelfanatyk.com/blog/wheel-building-tip-no-5-be-a-wheel-whisperer/

I totally recommend it.

 

[Ruadh495]

I'm having this problem with my rear wheel at the moment. It's a new wheel, built by a company in Germany who supply via Amazon at a very competitive price, so presumably machine made. I've had 4 broken spokes so far, all gone at the elbow. I put it down to hub brakes, which can apply a lot more torque than either pedal or motor, but I've also noticed the elbows are not snug against the hub flange. I've taken to carrying spare spokes, which I'm sure only long distance tourers used to do. Washers would help, but I'd have to rebuild the wheel to fit them.

My motor wheel is the front, presumably built in China (though it could be a UK build, EBC kit, anyone know?). That had a couple of loose spokes to begin with and has never been very true, but no real trouble.

 

[trex]

you should learn truing your wheels rather than carrying spares and replacing broken spokes. Machine spoked wheels usually need re-truing when they are got out of storage because the spokes are loosened. They usually need taken up about half turn to a turn. The other thing to keep in mind, you need to ensure that your wheel must line up with the middle line of the frame, otherwise, spokes will keep breaking.

 

[Ruadh495]

you should learn truing your wheels rather than carrying spares and replacing broken spokes. Machine spoked wheels usually need re-truing when they are got out of storage because the spokes are loosened. They usually need taken up about half turn to a turn. The other thing to keep in mind, you need to ensure that your wheel must line up with the middle line of the frame, otherwise, spokes will keep breaking.

Both of those are possibilities. I did prestress and true both wheels when I first had them and at about 100 miles, but it's something I'm in the process of learning so I'm not brilliant at it. Misalignment in the frame (bent frame?) is certainly also possible, but wouldn't that cause spoke failure on one side only?

 

[Ruadh495]

The first time I found a broken one I put it down to just a bad spoke, but started carrying a couple of spares just in case. Then I got 3 at once. Haven't had any since, so maybe it was bad spokes, though I did retrue the wheel once I got home, so that might have something to do with it.

I do use so pretty terrible roads and sometimes carry loads on the back rack (dead Muntjac, 30kg of trout, that sort of thing) but the previous wheel never had spoke trouble.

 

[trex]

Misalignment in the frame (bent frame?) is certainly also possible, but wouldn't that cause spoke failure on one side only?

no, I meant correct dishing so when you look from the rear wheel to the front wheel, the bike is symetrical along the middle line.

 

[Ruadh495]

no, I meant correct dishing so when you look from the rear wheel to the front wheel, the bike is symetrical along the middle line.

OK, thanks. It's not that one then. The rim is centred in the chainstays. It's a hub geared, coaster brake wheel so symmetrically dished, or close to. Replaced a hub gear drum brake wheel, so that should be the correct dish for the frame.

 

[trex]

I do use so pretty terrible roads and sometimes carry loads on the back rack .

would you consider a full suspension bike? a rear suspension would help eliminating broken spokes.

 

[Ruadh495]

would you consider a full suspension bike? a rear suspension would help eliminating broken spokes.

I suspect that would change a device for breaking spokes into a device for breaking racks, or maybe seat posts. Are there racks for suspension bikes which will take 30kg?

I have owned a full suspension bike, which I bought because of the quality of the local roads. Found it very hard work (it was a cheap one) and eventually got rid.

A trailer might be the best answer when I'm expecting to carry a load, but it's not always expected ( a choice roadkill, for example).

 

[trex]

yes, the Thule will take 60kg easily or a trailer as you said. Marwoodhill has a trailer that carries his other half.

 

[Deleted member 4366]

When you get 4 broken spokes, you should rebuild the whole wheel.

 

[Ruadh495]

Marwoodhill has a trailer that carries his other half.

Isn't the correct device for that a tandem ;-)

 

[Ruadh495]

When you get 4 broken spokes, you should rebuild the whole wheel.

That's probably what I will end up doing, if it continues to misbehave. Maybe upgrade to a 7 speed hub and use the stainless steel rim from the original rear wheel. When I bought my current rear wheel I didn't realise wheel building was something you can do at home (and it cost the same as a loose hub, which probably says something about the quality of rim and spokes...).

 

[Georgew]

When you get 4 broken spokes, you should rebuild the whole wheel.

That's true....it indicates that there's fatigue at the elbows and all spokes should be tightened to their proper level, stressed and de-stressed before ensuring that the spoke tensions are all within parameters. The problem is that machine-made wheels are usually radially correct but the machine cannot carry out the above procedures which are essential if the spokes are not subject to fatigue. I tend to buy factory-made wheels as they are cheaper than buying the same components and building my own wheels...but I always go through the above procedures before I use them.

 

[Georgew]

I suspect that it is the bend that gives the trouble.
I do wonder if the older spokes had a slightly different shape at the bend, or received stress relieving treatment after being bent.
It really doesn't matter about some of the explanations given here.
I contend that modern spokes are prone to snapping, older spokes were not.
If this is the case, why aren't manufacturers doing something about it?

Not true I'm afraid. "Rustless" or "galvanised" spokes of yesteryear were never as strong as today's spokes and broke with monotonous regularity. Good quality modern stainless spokes are made with superior materials and superior manufacturing processes and the double-butted ones are designed to flex and elongate which reduces fatigue at the elbow. That said, the most important element in ensuring a strong and durable wheel is not the components used but the builder.

 

[mike killay]

Not true I'm afraid. "Rustless" or "galvanised" spokes of yesteryear were never as strong as today's spokes and broke with monotonous regularity. Good quality modern stainless spokes are made with superior materials and superior manufacturing processes and the double-butted ones are designed to flex and elongate which reduces fatigue at the elbow. That said, the most important element in ensuring a strong and durable wheel is not the components used but the builder.

if you read my original post you will see that I am speaking from 65 years of experience with spokes, bikes, motorised bikes, motor cycles and my old MG Midget.

 

[Georgew]

if you read my original post you will see that I am speaking from 65 years of experience with spokes, bikes, motorised bikes, motor cycles and my old MG Midget.

Err....well done but I have over 65 year's experience with rustless spokes on bikes......mind you it could have been one year's experience repeated over 65 years.
I've repaired bikes and wheels for paying customers and KTM in this thread has also built wheels for a living and I'd be interested in his opinion on the subject.

And again Sheldon who usually knows about these things said:
"The material of choice for spokes is stainless steel. Stainless is strong and will not rust. Cheap wheels are built with chrome-plated ("UCP") or zinc-plated ("galvanized") carbon-steel spokes which are not as strong, and are prone to rust."

 

[Deleted member 4366]

Galvanised mild steel has a much higher fatigue resistance than stainless. I would have thought they would last the longest. Is mild steel strong enough? I would have thought so.