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Replacing a Spoke

ikedawilliams

Speeding Up
Oct 15, 2010
669
11
I had a quick look to see if this topic had been covered, but did not come across anything on the TCC. So...

I broke a spoke on my road bike for the first time last weekend. I had broken one before on my MTB but stopped riding it, and never fixed it, because I have a history of being taken to the cleaners when bringing a bike in, and figured it would be 5,000 yen to true the wheel and have a new spoke put in, and then while I am at it I should really get new tires and well... thinking about that cost, maybe it would be better to just get new wheels or new used ones anyways... I was not riding my MTB much at the time and always put it off.

I got a 5,000 yen tool kit when I got my first road bike in January this year and have been pleased with it. I felt confident enough to replace the spoke myself on the road bike and thought I should do the MTB at the same time. Both broken spokes were on rear wheels. The MTB on the drive side and the road bike on the non-drive side. I had the tools to remove the cassette and get the broken spoke out on the MTB. The road bike was easier. I brought the pieces to Y's today in Nikotama and went to the repair counter.

I had both pieces of the MTB spoke so the total length should have been easy to figure out I thought. Also, I thought there were only about 3 sizes of spoke for MTB, road bike and whatever - like small, medium and large for each wheel size (26'', 700C, etc.) I instantly got a bad vibe from the staff as I approached, yet proceeded to show him the spokes I wanted replaced and he said it was impossible to tell without complete, intact spokes. I said just hold the two pieces together and he would be able to get the total length, but he was very reluctant to do it and sighed several times throughout the process. I didn't know it, but it seems they do not sell standard sized spokes there. They custom cut spokes with threads on the end, then re-thread them depending on the size. All that was missing on the road spoke was the head - the bit that goes into the hub, but he said that was impossible to replace without a complete spoke. I was satisfied I could leave with at least one spoke as it is a 4km round trip walk and with a 2 year old kid in tow, it is not the quickest trip.

Seems every time I want to go to a bike shop it is a Wednesday. One good thing about Y's is that it is not closed on Wednesday, when all the other LBS's around me are. Another good thing was that it was only ¥46 for the custom cut spoke. No typo there. It was basically free, and probably didn't even cover the labor cost of ringing it through the till. Go figure.

I was also happy to throw them some money for some more chain lube, but they were out of the regular size, some grease but they wanted 1,350 for a small tube of it and I imagine I can get grease at the hundred yen shop, and a Top Peak Road Morph G with gauge, but they wanted 5,000 yen and it was under 3,500 on Wiggle, so I left it at that.

After another trip tomorrow or the next day, I should have the spoke I need for my ride on Saturday. Fingers crossed.
 
Actually spoke length is pretty critical. Generally they are sized within 1 or 2mm. BTW - Proteck in Ebisu will also custom cut and roll spokes for you. But this really only works with round, single butted or constant thickness spokes. for double or triple butted spokes, or flat blade, you generally need to get the right length spoke.

When you replace it, tension it so when you pluck it, it sounds similar in pitch to the other spokes on the same side. Then work your final truing from there. If a spoke has broken, it means either the rim has experienced extraordinary stress - or the spoke itself has fatigued. If the rim has been over stressed at that point - then it may be 'set' out of true and will require some extra TLC to massage it back. Work on the radial (roundness) before you work on the wobble. And always work from rightside (DS) to left (NDS) if you're on the rear wheel.
 
Yeah, what Tim said^

Also, where abouts did the spoke break? I have never broken a spoke on my road bike (touch wood), but have broken countless on BMXs. They usually go around the elbow where they thread the hub, so would be interested to know where yours went on the road bike.

Are the spokes regular ones, or are they any fancy shape / material?
 
Thanks for the info!

FYI: Just standard spokes. When I was twisting the nipple (sounds more fun than it was) the MTB one snapped about 3cm from the rim. I think it has seized up and that if I had sprayed a little WD-40 in there first it, might not have happened. As for the road bike, that one came off right at the elbow as I was on a decent. I don't recall any major bumps at the time and thought I might have gotten a flat, but I learned later it must have been the spoke I heard at the time.
 
Yeah thats normal.... I've had front spokes break on the front and rear wheel for no apprent reason. You may have dinged it when leaning the bike against something or from road debris flicking up many reasons..... Voodoo sometimes play a part along with solar flares.

Oneof the main reasons though why spokes break is because 99% of riders do not service thier wheels. Most factory built wheels by major brands actually state that you need to get the wheel retensioned after the first 1,000km. if you are heavier then its less (Especailly if you are over the recomended weight allowance for the wheel)

Custom built wheels normally need a setting in period and require 3 visits within about 200km to get the wheel tensioned for your riding weight and style.

I suggest you take thewheel in for a service and get it fully serviced as the spoke tension for the whole wheel is normally set way off after you brrake a spoke, especailly for wheels with low spoke counts and you will probably snap a few more over the coming weeks or ride as some spokes will have more tension on them now than overs.
 
Yeah, I second all that FarEast just said.

I have built a lot of BMX wheels, which while not quite the same as road wheels, obey the same basic principles;

Build them, make sure the tension is correct, de-tension the spokes (on a BMX wheel, this involves standing on the wheel - do not try this on a road wheel), ride it for a while, then go back and service it. On a BMX wheel this is a matter of days / hours if ridden hard due to irregular loads / stresses. On a road wheel this is a longer amount of time, but less than you think.

My new Mavics I bought, I had checked and trued / tensioned fairly soon after buying. I am taking them in again tomorrow to get them checked again, and I haven't even ridden them that much. There is a tiny bit of left and right on both the front which will be teased out by the wheel builder and all will be beautiful again.

Feels like when you have loose laces on your shoes and you do them up again, not too tight, but just right. Your whole body feels good.

Keep the wheels checked!
 
Just wondering... (and probably a dumb question)

Do any manufacturers/wheel builders offer (for lack of a better way to describe it) "pre-stressed wheels"?

That is, according to the comments above, a set of wheels would be effectively 'used' or burned in, on a machine or rollers or some such? Stressed as tho they had been ridden and then re-worked according to the above?

As per those comments, I do understand that actual riding by the customer would be the best way to go, but given a rider's riding style and weight, maybe almost the same adjustments could be made before delivering the the wheels to the customer?
 
As FarEast correctly pointed out, riding a set of wheels in gets them used to the way you ride; any particular way you lean on the wheels, the amount of stress you give the drive-side, your weight on the ballooning of the spokes etc. This (without some kind of peta-flop level stress potential modelling computer) is not possible to predict.

De-stressing as I was referring, is when you lace up a set of wheels correctly, then jump on them (if they are BMX wheels) or just ride them (if they are road wheels), then re-adjust the tensions.

The theory is, when you build a wheel, you are assuming that each spoke and nipple is the same length, and the hub and rim are perfectly round. They are not, of course, so when you lace up with this as your control, you are forcing things a bit against their nature. Once you do the initial de-stress, you are setting threads male-female to hard seat, you are seating spoke heads hard into the hub, and bedding the spoke crossings in to each other.

This all adds tiny amounts of play to the tightness you originally set, which need taking up, or indeed loosening.

If you want to think about it simply, it is just 'bedding in'.
 
Build them, make sure the tension is correct, de-tension the spokes (on a BMX wheel, this involves standing on the wheel - do not try this on a road wheel), ride it for a while, then go back and service it. On a BMX wheel this is a matter of days / hours if ridden hard due to irregular loads / stresses. On a road wheel this is a longer amount of time, but less than you think.

We do that on road wheels to mate.... don't stand on them just put the full force of the upper body on them.

Just wondering... (and probably a dumb question)

Do any manufacturers/wheel builders offer (for lack of a better way to describe it) "pre-stressed wheels"?

That is, according to the comments above, a set of wheels would be effectively 'used' or burned in, on a machine or rollers or some such? Stressed as tho they had been ridden and then re-worked according to the above?

As per those comments, I do understand that actual riding by the customer would be the best way to go, but given a rider's riding style and weight, maybe almost the same adjustments could be made before delivering the the wheels to the customer?

Most of the big companies like Shimano and Mavic have this Vodoo down to an art so they can guage the tension and build of the wheel to almost perfection thus why these wheels only requireservicing after about the first 1000km . Some companies and a torturetest that they put the wheels through formaybe 1hour and then go back and check the tensions.
 
I have yet to break a spoke but I just realized that when I started to ride seriously about 8 years ago my wheels would often bend on to a brake pad on bends and some times on sprints....

I now ride / pedal better from using rollers etc and am much kinder to my spokes in that regard....

I'm quite heavy :eek: but my wheels ( old and new) have no wobbles....

I want to practice wheel building and tuning with an old wheel I have in preparation for the day I need to do it but have never bothered to learn.
Knowing me, I'll probably end up getting my boys at SEO to do it for me ( for free ) :cool:
 
Care with WD-40

Thanks for the info!
I think it has seized up and that if I had sprayed a little WD-40 in there first it, might not have happened.
From experience, I know that getting a can of WD-40 near your braking rims or your braking disks is not especially satisfying either. The stuff is mildly corrosive, too. It's probably highly flamable, so I'm sure MacGyver could turn it into a high-octane blow torch...

I have only broken spokes on a MTB as a result of a branch through the front wheel, so your thread has been interesting to follow.
 
I've built hundreds of wheels. Spokes break especially if the tension is not equal and either too high or too low. They usually break at the head cause that's where the highest stress riser is. But under severe pounding, they'll break at the nipple, pull through the rim or just about anywhere. Spokes will also break if the hub is not de-burred and the constant scratching against the spoke 'J' will eventually score it enough to cause a weak joint - then 'bam' - it's gone on the first bump. A wheel literally 'hangs' from the spokes - so when a spoke breaks, it is typically spoke at the TOP of the rotation. Funny, huh?

Building a wheel is very simple and very hard at the same time. But the most direct advise is:

1) Build the driveside first, then the non-driveside.
2) Start with about a 25, then 50, 70% tension getting the wheel perfectly round. Don't worry about wobble yet.
3) Then tension the non-driveside equally until you have proper dish.
4) Then go back and work the wheel into true (round first, then wobble) until you have all the spokes at about 95% tension.
5) De stress the wheel alot during this phase. Squeeze the spokes, press on the center, etc.
6) Bring up tension gradually and pay attention to both round and wobble - it's not all about tightening - it's alot about loosening. So - you need to always 'mind the center' and loosen or tighten to achieve that balance.
7) A perfect wheel will have spokes on either side at equal tension - +/- 5% , if you're building a freewheel wheel, then the driveside will have about 10-15% higher tension than the non-driveside.
8) If you don't have a tensionometer - then shoot for about an 'A' on the DO-Re-Mi scale (if you're a guy) I know this sounds really wrong - but it mostly works. If you're in doubt, pluck the spoke on your other wheel and you can go from there.
9) If you have a tensionemter - then you can make sure closely. Most wheels build up quite nice at about 125 - 155 kgf. Some higher and some lower depending on a zillion things.

Other tips:

1) Use spoke wrenches that grip the nipples from 3 sides. The stupid 2 side wrenches are worthless and will just round your alloy nipples into mush. Get them from DT, VAR, Sapim, etc. Everyone who makes good spokes, makes good spoke wrenches.

2) Soak the nipples in oil for a few days - or just keep them there. Personally I use olive oil. Why? Cause it's cheap, smells good, easy on the skin, and dries a little sticky. Some people swear by linseed oil as its even more sticky. Either way - these are both good oils to prelube your nipples with.

BTW - Liquid Wrench is one of the best pentrating oils. WD-40 is more for protection and water dispersal than anything. Also - just automatic transmission fluid is an awesome pentrating oil - if you mix with a little acetone or methyl ethyl ketone, it works wonders on frozen parts. BTW - ATF/Ketone mix IS a bit corrosive - so you don't want it sitting on painted /finished sufaces very long. And it will damage gelcoats and resins of composites. So - it's a big NO NO on carbon wheels and parts.
 
Tim, totally agree with everything said ...includingthe olive oil trick something my grandfather taught me as well as my old mentor from Excelsior days.

One thing I would disagree on though is lossening spokes I was taught that this is a cardinal sin and actually weakens the spoke, especailly when having to replace a broken spoke.
 
Owen , to be honest I don't know it was something that both my wheel builder in the UK swore by and also Hiyoshi at Sagami cycles swears by.

One way to explain it:

Assume we have spokes A, B, and C on the same side of the wheel. If A and C become loose and B does not, B will continue to hold the wheel straight until it breaks or you loosen it. So, it is a better philosophy to assume the wheel was made correctly and not to loosen any spokes unless it is unavoidable. Even then, it should be only one or two spokes that are too tight; otherwise, the rest are all too loose.

Another reason is that as you tighten a spoke they twist especailly cross over spokes. If you lossen any spoke durring the build they tist the oppersite way, thus weakening the structure of the spoke.

An example of this is bending a spoon, you can bend a spoon in half and the structure of the spoon will remain somewhat intact and retain its strength across the bend, but as soon as you bend it in completely the oppersite direction the metal becomes brittle across the outer arch that used to be the inner.
 
Wheels are built on the principal of the triangle.

There are many triangles in a wheel, which increase with the number of crosses one puts in the spoke lacing.

Loosening a spoke will not change the triangular patterning, and will not weaken the spoke.

If loosening spoke tension at the nipple did, in fact, weaken the spoke strength, we would have to lace all wheels radially, as according to your Yuri Geller physics, bending a product back and forth will cause to eventually break, so the crossing of two spokes will eventually cause snapping from riding.

I can understand that a loosening of spokes may cause problems if a wheel is not destressed, but done properly, and this has been given to me verbally by Dave Hinde and George French, it is standard practice.
 
@James; loosening spokes weakens them? How so?
I wouldn't think it weakens the spoke, if done carefully. However a spoke can't possibly work itself tight during use, only loose. So if the wheel was built properly... OK it's a big "if".

Incidentally I think The Bicycle Wheel by Jobst Brandt is an excellent read.
 
Actually I believe everybody is 'right' to a degree. It all depends where in the build process you are, how the wheel has been behaving under riding conditions , and also after a high stress event, what issues may have developed. Modern spokes are constructed so as to have an optimum tension range that is actually very close to over-stressing and potentially work hardening the steel which in turn could cause brittleness and lead to failure under an excess event. Tension is everything.

If you start loosening spokes that are brought up to correct tension - without making sure the spoke body is anchored - then you will cause the 'reverse spoon issue' and the spoke will work harden a bit. If this is done too many times - then your spoke becomes very brittle and will be in danger of breaking. What I'm referring to by loosening is in the build process where you need to balance all spokes in perfect tension to achieve the correct runout, dish and wobble. Most people with no experience will just keep cranking on a spoke to hog the rim over without realizing they are actually overstressing the rim in that segment, plus potentially exceeding the spoke's tension range.

After a wheel has been bonked - then you can throw more caution out the door, cause if the wheel was really bonked, then rim will have been deformed and the tension required at some segments will be different than a perfectly unbonked rim. But again - you need to mind the tension all the way around - and if it is wholly out of range, chances are the wheel is never going to be a reliability candidate.

I rarely, if ever, loosen a spoke after the wheel has bedded in. If I have to, then something radical has happened to that wheel. And if you loosen, the re-tension spokes that have been brought up to a full tension before - it's not good. You need to overstress (stretch) them to get the same consistent tension - and then the spoke has a narrower operating range.

A wheel should be built (with max reliability in mind) so that any deformation of the rim within reason will not over-tension the spoke to failure. Some builder say build the wheel so tight that you have max stiffness to begin with and if you'd hit hard enough to damage the wheel, well, you are probably whistling Dixe with the Devil. And other people say run them a bit on the loose side so that extreme events will allow some deformation, but the spokes operating range will keep up with the deformation and not break, thus the wheel's integrity will be maintained.

Again, personally, I just rely on the spoke mfg recommendation for tensioning, and the rim mfg. Then interpolate a little based on the rider's habits, desired use, etc. And actually I'd be more inclined to change the lacing pattern than spoke tension anyway to build up the right wheel for the job.
 
wind up

I was taught when the wheel is nearing completion and close to its desired tension you are to unwind the spoke by loosening the spoke just under a quarter turn. I was told this is because the spoke actually twists a small amount when you are aproaching final tensioning and if you do not unwind it, it will unwind when the wheel is ridden causing the wheel to go untrue. It was said that a sign of a master wheelbuilder is that you will not need to re true the wheel after the build. I myself have not built a wheel that has not needed to be re trued after building, so take it with a grain of salt. As far as loosening a spoke I avoid that at all costs, I would say this would be classified as unwinding, but indeed loosening has been neccesary and the only cure (if the cure is a perfectly straight wheel, which to some is not the most important thing, to some tension is king and a little wobble is OK)
Also some people have said that the non drive side can be dry as in no oil or spokeprep but the drive side needs something to ease the friction of the higher tension. I swear by DT spoke prep and use it on all spokes, drive and non. I have used grease and had problems with loosening spokes. Linseed I heard is good because it will will dry so you dont have to worry about spokes loosening.
Just a few Ideas, Tomatoe-Tamatoe!
 
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