LV2TNDM

Disagree about tension not being important. It's crucial. And when you quote someone who makes possibly THE most precise and nice spoke tension meter on the market, it's kinda funny:




Hjertberg has been a pretty big advocate of accurate spoke tension measuring for a long time now.

I'd say the OP's problems are twofold: Crappy OEM wheels with dirt-poor spoke quality AND machine building with zero attention to even and appropriate spoke tension.

Rebuild those wheels with double-butted DT or Sapim spokes and achieve proper, even tension, and the OP will be set. Unless he weighs 350 lbs. and bombs rock gardens with flat tires on that bike!

PS And DT's spoke tension meter retails for over double the cost of the one above. Crazy!

cyccommute 

The common advice is “follow the manufacturer’s recommendations”. I haven’t seen anyone say “well follow it to ±20%”. If a manufacturer says to torque a bolt to 20 foot-pounds, do you torque it to between 16 and 24 foot-pounds?

As to the spoke tension overall, again the common advice is to have even tension. I don’t disagree with that but how even is “even”. The ranges of suggestions from the few manufacturers that provide them are already quite wide…roughly ±10%. If you go ±20% that’s now ±30%. That’s a huge swing and not really all that useful.

cyccommute 

I know it’s fun to pile on but go read what I wrote again in the context of the thread. I didn’t say…and have never said…tension is unimportant. I never implied that Hjertberg says tension is unimportant. I was disagreeing with the idea that tension is “the single most important thing to do to make wheels strong.” Hjertberg’s own words don’t mention tension to make the wheel stronger, probably because he assume that the tension is right to begin with. Hjertberg opens that article with this statement

and then goes on to discuss the strength of the spokes without mentioning tension.


I don’t disagree. However the advice of just increase the tension or replacing the wheel with another machine built wheel is bad advice.

Or rebuild with triple butted spokes and the bike will be able to bomb those rock gardens. It won’t hurt to use triple butted spokes. They do everything the double butted spokes do with a large margin of strength.

What’s the downside?

e0richt

ok! thanks... I will check that out as well!

cyccommute 

You could have bolded it, underlined it, and put in italics. You are still wrong.

Keep repeating that to yourself all you want. It’s never going to be true.

Yes, I agree. I just see it from a different perspective as to who is shoveling garbage.

Kontact 

Some points that seem to be confusing to some people:

1. Spokes normally don't break on well made wheels.* If anything, the spokes on a good wheel will outlast several rims and possibly the hub.

2. 14 gauge elbows don't break on correctly built wheels. They break on wheels built by amateurs that have never received real instruction, and they break on machine built wheels because the machine isn't able to seat the elbows, stress relieve or balance tension. Thick, 2.3mm elbows are designed to counter poor wheel assembly, and are even advertised for use by machine wheel builders.

3. Butted spokes are more elastic, and are able to make up for under-tension, over-tension and sprung elbows better than straight gauge. A well built wheel doesn't require butted spokes to last, but butted spokes are lighter and ride nicer - so there is always good reason to use them.

4. Stiffer rims flex less vertically, which decreases the tension range that each spoke sees every revolution as it goes past the 'flat spot' on the ground. For a given rim weight, taller rims are stiffer than shallower rims. For a given shape, thicker walled/heavier rims are going to be stiffer than lighter/thinner walled rims. Smaller tension deltas mean less work cycles on each spoke, decreasing the wear and tear on each spoke. This is why you can build a 36 hole wheel on a 270g rim and have it last - the spokes are closer together to minimize the flex of the super light rim. And it is also why 20 hole wheels tend to be built on tall, 500g rims that are stiff enough to have large unsupported spans between spokes.

5. High tension spokes vary in tension less than low tension spokes per revolution. But they have a greater static load on themselves, which is its own source of wear. But low tension spokes get cycled much harder as they approach zero tension at times and then 'snap back' into tension.

6. The correct average tension per spoke needs to be based on both the spoke itself and the number of spokes being used. If you go to high tension on a light weight, 36 hole box rim, it will potato chip as you build it. Use the spoke count and the suggested tension range to suggest a reasonable spoke tension for the wheel you are building. Low count=higher tension, high count=lower tension in the range.

7. Nice rims are those that are extruded, pinned and machined so well that perfect straightness comes at very even tension. Less exacting rims require some spoke tension variation to force the rim into true. That's okay, as long as the tension variations are fairly smooth one spoke to the next. But it is sometimes better to accept a slightly less true wheel (especially near the seam) if you can keep tension more even.

8. Even cheap modern spokes are pretty reliable, and even cheap modern rims are straighter than older rims. So fairly modest wheels can last very well, if the deficits of machine building are addressed by seating the outside elbows and evening tension.


*Modern carbon rims have a tendency to break spokes on hidden nipple rims where the nipple enters the rim.

Kontact 

The reason I detest dealing with you (aside from the graphs, flow charts, pseudo science, paragraphs of yada yada and insults) is that you can't be bothered to read.

I wrote that machine built wheels, gone over by the bike mechanic to address tension and seating, will be a good wheel. You ignored the "gone over" part, then kept ignoring that is what I was talking about despite pointing it out to you twice. A total knucklehead move.


The problem with you is that the shear volume of intellectual-adjacent stuff you write will suggest to people that your ridiculous points about tension, rim design, etc, might have some validity. And those unfortunates might act on that wise sounding advice, instead of using time tested advice from people with much more quality experience than you. Many of us learned wheel building from experts. You learned by trial and error, and you didn't learn what we have.


Of course you have a lot of experience with broken spokes. You aren't building wheels correctly, and you are too 'smart' to accept anyone else's suggestions as to why. Instead you think any wheel without oversized elbows is garbage. Redic.

Deanster04

which end did the spoke break…nipple or hub end? Makes a difference. Talk to a shop that has a wheel builder after you check. SS SPOKES only break if bent. Built many wheels with modern spokes and have NEVER broken a spoke even after a crash.

Kontact 

SS spokes break all the time. Especially in carbon wheels.

His spoke broke on a heads out j bend.

e0richt

it broke at the hub end... the LBS mechanic is not good with wheels (as I have found through experience as my trek 7100 had similar problems...)

Deanster04

Sorry, old school no experience with straight spoke builds only 3 or 4 cross. The tension on a straight spoke build is much greater than the X build. Usually custom spokes are required. My experience goes back to pre 1970's where the spokes were sub par because of manufacturing methods used. Good luck. Deanster04!

Kontact 

Carbon wheels don't use only straight spokes. Crossed j bend spokes commonly break in carbon rims.

Deanster04

I was thinking when the wheel was built the spoke was bent enough to cause weakness. Check the tension on your spokes before you use the wheel. I have a couple of very old rims that are still aligned very well inspite of many miles. Machine built wheels can be a problem with an already defective spoke. I also noted that many wheels with straight spokes have lower counts so the tension is not distributed very well. I know that I have used and tried a variety of straight spoked wheels and always ended up with a sore butt...they look sexy but are a real pain in the ass. Although I have tried MANY configurations and bike materials I now use a steel frame form the 1980's. From a material perspective I like the Greg Lemond bikes built out of Reynolds 853 tubing so I'll probably look online for one of those bikes: Poprad steel (gravel XC) is the best. In my opinion...which is like an A**H*** everyone has one.

Deanster04

Again no experience with carbon wheels...and don't expect to ever have any. I'm over 80 and still ride pretty old bikes at least 50 miles a week in the summer and when ever during the winter. Boulder is nice W.R.T. snow and cold. I also have a trainer set up in my basement that gets a workout. My gravel bike is a Ritchey Breakaway that has ridden many a pass in the Dolomites, French alps, and Spanish Par... Have slowed down but only a little. Bike riding is still the best exercise...Deanster04

Kontact 

I guess that's the problem with making broad pronouncements.

JohnDThompson 

The importance of even spoke tension is inversely related to the number of spokes in the wheel.

Jeff Neese

Maybe - it depends on the application. If something just needs to be "tight enough to hold together but not to strip the bolts" then 16-24 may be perfectly fine. In that case we would refer to 20 foot-pounds as the nominal value, but the actual torque can be within 20% of that and still work for that use case. I might even be able to just use the torque setting on my cordless drill and that will be good enough. Other applications obviously require greater precision, along with a more accurate and precisely calibrated torque wrench.

About 20% is the most commonly seen figure. My wheel guy gets it a lot closer than that, and even gives me a printout, probably generated from the Park Tool app.

cyccommute 

You are really working hard to make 20% variance sound reasonable. Nothing I’ve ever read on torque says to “get it into the ball park”. There’s error in torque wrenches, of course, but the variance isn’t ±20%. That “about” territory not anything that is accurately measured. You might as well just not use the torque wrench at that point.

And 20% is a wild ass guess. That “20%” isn’t the total variance. Pick a value and it can be 20% above or 20% below. That’s neither an accurate nor precise measurement. I could probably get to that level of accuracy just by squeezing the spokes. It’s not much of a standard to aspire to.

Jeff Neese

Maybe you could. A lot of people claim they can do it by ear (plucking the spokes) or using a guitar tuning app. I don't know of any professional wheelbuilders that do it by squeezing or plucking though. Every one I've ever dealt with uses a real tensiometer.

It's not just a wild-ass guess. 20% relative spoke tension is a fairly common standard. It's even the default in the Park Tool Wheel Tension App. I think we can agree that you'd like to come closer than that if possible, but that needs to be balanced with making the wheel true, so variance is acceptable and expected.

You seem to feel that 20% is too wide a variance. How close do you get on the wheels you build?

Kontact 

Tensiometers are fairly crude, so I use them to get in range and pitch to fine tune.

FBinNY 

Allow me to.introduce myself. Built my first wheel in 1966. Built countless wheels since, mainly for racers and tourists. Before THE BOOK nobody had tensiometers. The only one around was the Hozan, which was only used as a QC tool in factories.

Even tension wasn't an issue, because rims were much lighter, and it was difficult to build an aligned wheel with uneven tension. Some rims, including Fiamme Yellow Label, and Araya track rims were so aquirrely that the least error would show. Even with no conscious effort any decent builder was consistently producing tensions within 10% purely through good technique, and calibrated fingers.

When I started distributing Wheelsmith spokes sometime in the 80's I swiped a tensiomerer from stock, and still use it to check my "calibration" taking 3 readings off finished wheels.

Like other old tech builders, I still use my thumbnail and ears to confirm that tension is uniform.

Jeff Neese

What's 20% of C#?

Jeff Neese

I understand. When aligning a radio, a lot of us "old timers" can do it by ear and I can get it pretty close. But since I do actually own a signal generator and oscilloscope, I don't have to do it by ear. I bet we can think of a lot of examples where "back in my day, we didn't need no stinkin' ____" (fill in the blank).

If I walk into a shop and their wheel guy says he doesn't own a tensiometer and just does it by ear or by feel, I'm not leaving my wheels with him.

FBinNY 

You sort of understand, but not quite. Those of us who learned without tensiometers, developed habits and methods that maintain even tension throughout the process.

Let's use pancakes as an analogy. Folks who don't know better end up with lumps in the batter that they need to work out. Experienced cooks know to stir in the liquid slowly, so they get smooth lump fee batter straight off. Saves time, effort, and because the batter isn't overworked, end up with lighter, fluffier pancakes.

So, I must travel in different circles than you, but none if the highly regarded builders I know use tensiometers for anything but final QC.

cyccommute 

The problem I have with the ±20% recommendation is that you can get that kind of variance without using a tool on it. Why spend the money on the tool then? The tool will let you get closer than ±20% so why not use it to do so?

The other problem I have with that recommendation goes back to “all you need is tension” idea. Everyone assumes that the wheel build is bad and that the tension is uneven when spokes break. They never consider that the problem might be with the spokes themselves. My wheels have always been tight and even but even with double butted spokes, breakage was an issue. Going to a spoke with a heavier head stopped the breakage issue. I didn’t change the way I build wheels…they are all built tight and even. The only thing that changed was the spoke. For light riders, they may never break a spoke even on, admittedly, commonly badly build OEM wheels. Heavy riders will likely even break spokes on well built wheels.

Triple butted spokes fix the problem and prevent future problems. I have never been able to understand the resistance to this idea for heavier riders or heavily loaded bicycles.