Breaking Spokes

[porky]

On another point, "how come some wheels just never go out of true, let alone break spokes??.

 

I have a set of VELOMAX wheels I used for years and years, I rode them constantly, bounced over pot holes, raced on them and  they never once even went out of true, in fact they are still perfect (although they are here in the cupboard now) - yet some wheels just need trueing every few months.??

 

[dollar]

I have seen that some hubs wear more than others. Some rims settle in more than others. I guess that some spokes strech more than others etc etc.

 

I am not a total s/steel convert. It's nice for corrosion but it also has a few other nasty properties.

 

[Johan Bornman]

Agreed. There is one point that I would like to make that I dont see yet. Spoked wheels need pretty constant maintenance.

Many of us allow our spokes to go a bit pap over time and this leads to problems. Remember that as some of the spokes loosen up it places more stress on the others around it.

You need to check your spokes every week or so to ensure that they are all at the same tension. If you find a shirker he needs to be sorted. Dont touch unless you know what you are doing!!

 

I disagree. Well-built spoked wheels require just about zero maintenance. I ride 16-year old wheels that have needed attention maybe three times in their life. Wheels subject to more abuse (and abuse is not from riding but lateral bumps to the rim) may need double that, but nothing like constant maintenance. Good wheels are buy-and-forget items.

 

Spokes that slacken are a sign of spokes that weren't tight enough to start off with. Tension is what keeps nipples from turning. The only way a tight spoke can loosen is if the rim starts to fatigue and collaps around the spoke holes.

 

A spoke that's does put more stress on the adjacent spokes but that's linear stress that the spoke can handle. It doesn't deteriorate those spokes.

 

 

[Johan Bornman]

On another point' date=' "how come some wheels just never go out of true, let alone break spokes??.

 

I have a set of VELOMAX wheels I used for years and years, I rode them constantly, bounced over pot holes, raced on them and  they never once even went out of true, in fact they are still perfect (although they are here in the cupboard now) - yet some wheels just need trueing every few months.??

 

[/quote']

 

Your observation is correct. If their tension is high, they'll never unscrew at the nipples and thus never go out of true. However, if they weren't stress relieved, have poor spoke arrival angles and weren't flattened against the hub at build-up, they will prematurely break.

 

There are two things at play here - tension and stress relieving and it is possible to get one right but not the other, hence what you observe.

 

[dollar]

Yes - If you have a well built wheel with perfect components you may never have to touch the wheel - agreed. BUT not all wheels are perfectly built with perfect components - only the select few

[Johan Bornman]

I have seen that some hubs wear more than others. Some rims settle in more than others. I guess that some spokes strech more than others etc etc.

I am not a total s/steel convert. It's nice for corrosion but it also has a few other nasty properties.

 

I don't know what hub wear is, I've never seen it.

 

Rims don't settle. They eventually fatigue and crack but I can't see how they can settle. It is not loose powder in a vibrating container or corn flakes in a box that shake into tighter spaces.

 

Spokes do stretch, but not as you envisage it. Lets first separate all the modes of stretch: There's elastic and plastic deformation. The former is temporary and happens at build-up and during each cycle of the wheel. The latter only happens at build-up and then never again unless the wheel is in a stick accident.

 

But, since they're all stainless steel, the strain is similar across brands if you compare similar cross sections. In other words, all 1,8mm spokes will display the same strain if subjected to the same force.

 

Your statement of "some spokes stretch more than others" is thus meaningless.

 

 

[dollar]

Are we going to spar a little 

 

The holes in hubs elongate over time. Soft material elongates more than hard. A very slight elongation will tend to loosen the spokes.

 

The nipple holes in the rims are constamtly being stressed and unstressed. Depends on the rim but they can work loose over time - thats what I mean by settle. Nothing to do with frosties

 

I bet you that my 25c spoke is going to suffer from greater permanent deformation than your R2 double butted spoke? No?

 

[Johan Bornman]

Are we going to spar a little 

The holes in hubs elongate over time. Soft material elongates more than hard. A very slight elongation will tend to loosen the spokes.

The nipple holes in the rims are constamtly being stressed and unstressed. Depends on the rim but they can work loose over time - thats what I mean by settle. Nothing to do with frosties

I bet you that my 25c spoke is going to suffer from greater permanent deformation than your R2 double butted spoke? No?

 

Yup, especially if you....what's the PC word for it??? Talk distruths

 

Spoke holes do not elongate and I challenge you to show me a hub with elongated spoke holes. I have some nice measuring equipment and I'll promise to take photos and post the results here.

 

I don't see how nipple holes work loose over time. They're simply spaces where there is no rim, how can a hole work loose?

 

I have no idea what a 25c or R2 spoke is, maybe D2 can shed light on the latter.

 

C'mon, you're cluttering what was a good discussion.

 

[Wyatt Earp]

 

 

 

I don't see how nipple holes work loose over time. They're simply spaces where there is no rim' date=' how can a hole work loose?

 

[/quote']

 

I agree, it's impossible.

 

However I have seen eyelets work themselves loose, but then again the amount of movement is minuscule and when the spoke is under tension they eyelet is under tension too.

[Johan Bornman]

Anton, you're right about the eyelets that come off. But as you say, when they come off, they make no difference. That's because the eyelet metal cracks right around the nipple on the inside of the rim and it falls off. A washer of material still remains underneath the nipple, hence the before and after dimensions remain the same.

 

 

 

[porky]

Hmm, I find the discussion quite interesting.

 

Last time I had my wheels trued, the shop told me they only used a spoke tension meter (or something similar, I cant remember the exact word) which ensured all the spokes were tensioned correctly, - I was quite surprised because I wondered how it could work, although I never had the time to ask.

 

It seemed like a bit of hocus pokus to me, but I wondered if there is any merit in having your wheels trued and the spokes checked with this method Johan? - dos it even work.?

 

[javadude]

 

All bikes of reasonable quality have stainless steel spokes and only the cheapest have galvanised steel spokes.

 

This is what annoyed me the most about my wifes bike. This was a Fuji Sunfire, not a department store special. I still have the wheels and the remaining spokes are so brittle i can snap them using the fingers on one hand.

 

According to the official specs the spokes were meant to be stainless, but who knows.

 

[Wyatt Earp]

Porky

 

 

 

When I build wheels I am glued to my spoke tension meter.

 

Replacing a spoke on a conventional wheel, doesn't bother me too much, I just use my feel.

 

Mavic wheels and other wheels as the older Shimano's,I use the spoke tension meter in abundance.

[Guest Big H]

Dollar, Dollar, Dollar...... are you questioning Johan Bornman??????...... do you want to be the resident Hub bike fundi???????, do want to say you know more about wheels??????? Always stick to Windhoek Lager.......... and remember I am watching you!!!!!!!!!!

[Guest Big H]

I also use a spoke tensiometer as an indicater to spoke tension. Final tension I use the "tyre lyre" method by twanging the spokes........ but there are varied opinions on the successfull use of the tensiometer.

[Johan Bornman]

All bikes of reasonable quality have stainless steel spokes and only the cheapest have galvanised steel spokes.

This is what annoyed me the most about my wifes bike. This was a Fuji Sunfire' date=' not a department store special. I still have the wheels and the remaining spokes are so brittle i can snap them using the fingers on one hand.

According to the official specs the spokes were meant to be stainless, but who knows.
[/quote']

 

I know the spoke you're talking about. They're high galvanised high carbon steel spokes that perform very, very poorly. The surface is rough and they're brittle as hell.

 

Here's a photo of such a spoke. It broke, like you say, like glass.

 

Good spokes are made from ductile, degassed stainless steel and don't break like that but in one smooth cut.