bigfred 

A messege to all of you who would like to comment on spoke tension in my thread, "Find someone who isn't already a member of the choir to preach to."

I wasn't unhappy with my Open Pro's. They had lasted years. They usually got an annual 'touch up', if that. For all my skills, wheel truing had never been one that I took the time to perfect. Instead, I believed it was best performed by someone who did it everyday and was "current" so to speak. I chose my wheelsmiths carefully and had good results for the most part. When I moved here, I went through great effort to find a wheelsmith who would respect the fact that the result they would be able to attain would be limited by the condition of my rims and the neccessity of maintaining reasonably even tension. Several, proceeded to declare that my rims would be "perfect" when returned to me. Rims that had been oh so slightly less than perfect for years but strong and reliable, had now become constant headaches. I looked around and finally found a new shop with a newish mechanic who while not as experienced listened to me and delivered the result I asked for, a well tensioned and balanced rear wheel that wasn't quite perfect. After all the thing has 20,000 or better miles on it. The result lasted about a year. When a 'friend' lead us on a ride that resulted in returning along an estuary during high tide. Hello mother ocean, good by corrossion resistance. Rebuilt most of the bike, but continued to have dissimilliar metal issues at the rim/eyelet/spoke junctions. Finally solved this by stripping wheels, including rim tape, and liberally applying WD40 to all spoke eyelets, nipples and through the valve hole. Cured corrossion issues, but, also eliminated spoke prep that had kept non drive side nipples from backing off. Voila, loss of wheel reliability. Possible solution could have been to delace and relace said rim with existing spokes while applying spoke prep. But, with old spokes and a decaying rim, that solution really didn't make sense. So the OP is being replaced with an MA3. Because, I happen to have a set of unsued MA3's that had been sitting around for a long time.

CXP 11's were take offs from my wifes bike. Took them into shop to get them tensioned. They came undone. Took them in again. Same result. Tried a different shop that I hadn't previously used. Explained, got a wheel back that seemed to have WAY more non drive side tension than I'd seen before. One week after putting back into service broke non drive side spokes for the first time in my 25+yrs of cycling.

Dead set to learn how to true and service my own wheels, set about truing the CXP 11's to find that they had used perminent loc tite. Can wind a spoke up to the point it breaks without getting the nipple to release. I've declared the wheel a candidate for rim replacement.

I'm glad for all you guys that have found lower spoke count or lighter wheels that work for you, your weight, riding strength and style. I'm really not to concerned about the weight of my training wheels. I don't care how few spokes they have. What I do care about is having strong reliable hoops. And with that in mind, no one can argue that more spokes can't/won't build a stronger wheel. The people who design, market and build wheels certainly agree. Every company that markets a wheel for 'heavier' use, uses more spokes than they do in their comparable "lighter" use wheel. Often without varying the rim or hub.

So sue me. I'm going to build some overkill and get back to cycling again, like I used to.

Buck_O

Based on the information you give in that post, i would say the choir leaves before the sermon.

vesteroid

Hoping to get some insight on this.

I am about 235 and losing weight almost every week. I am trying to get to 215 and see how that feels.

I had Peter white quote me a set of wheels and he recommended velocity deep v rims with 36 spoke and velocity hubs.

He wants 465.00 for,the wheels.

I am trying to figure out if the rims that came on my giant defy advanced 1 are not suited for my big but, or may potentially fail, and if so are the ones Peter is quoting the way to go? Should I be worried about weight between the two sets at all? I suspect the new ones are heavier?

Mr. Beanz

I build my own so I'd go with the parts online, you may also , seems cheaper

Deep V $61..................https://www.prowheelbuilder.com/veloc...-700c-rim.html

Pair of 105 hubs...........$70 https://www.ribblecycles.co.uk/sp/roa...pd/SHIMHUBR492

$195 then find a local builder to build them up for $150 total about $350.

I myself could do my own for $250.

Peter White does have a good rep. I ride 32 Deep V's at 250 no problem. Lasted 20,000+ miles with one minor true at 13000. Wheel bake surface wore out, wheel still true. I also build a set with 28 spoke, over 9000 now no problems.

If Peter W couldn't build a set with 32 spokes that lasted at your weight, I'd be shocked. I've heard mixed reviews with Velocity hubs, some say smooth others say rough.

As far as being heavy, yeah when I am out of form the wheels are heavy. When I train and lose 30 lbs, they are superlite on the climbs.

ericthered

Boy, how do you respond to some with over 12,000 post.

I was referring to my 32mm tire (which is my primary rear tire size but once again NOTHING UNDER 28mm) when I said that they were at 85 psi which seems in line with what Sheldon would recommend (he actually says 75).
https://sheldonbrown.com/tires.html
Tire width in mm
Wheel load 50 mm 37 mm 32 mm 28 mm 25 mm 23 mm 20 mm
100 lbs/50 kg 45 60 75 100 110 120 130
70 lbs/35 kg 35 50 65 80 90 100 110

The two comments that you glossed over were why I liked A719. 1) eyelets 2) wider.

There is also differences in rim materials that will make them more or less resistant to denting when subject to abuse. You can see this in discussion on mnt bike forum. Honestly, I cannot always dodge that pothole, railroad track, etc and un-weight as well as I would like in TRAFFIC. My current mavic a719 and previous alex dv15 did not dent in the same way as I experienced with the "bombproof" deep V.

I hold by my statement that I think the mavic a719 are a stronger rim and prefer them over the deep V. The $25 difference is cheap on the front end and I have plenty of places to lighten the bike above the saddle. I guess the real difference can be seen on Peter White's site. The Deep V is under "Racing" while the A719 is under "Touring". If you are looking for the strongest "narrow racing" rim, deep V, "My strongest narrow rim for racing. 30mm tall." My guess is that any of the rims in Touring are "stronger" than the deep V. The a719 might also be easier to build with the access to the nipples and eyelets over the deep V for a novice (considering OP).
Cheers
Eric

dehoff

If you weighed 220 and your bike plus all your gear was 20 pounds, the load on your rear wheel would be greater than the 100 lbs in Sheldon's chart. Throw in the fact that the tires may not have actually measured out to 32mm or the fact that they may have been 28's and your tire could have easily been underinflated.

If you take a look over at the Bicycle Quarterly Article on Tire Inflation, your actual load on the rear tire would have been 144 pounds if you were at 220 pounds and the total bike weight was 20 pounds (17 pound bike plus two full water bottles, and that's not including anything else you might have carried or were wearing). So, we're at a recommended 85 psi for a 32 and almost 110 psi for a 28 and you "usually kept them inflated up around 85 psi depending on the tire.", so they could have easily been underinflated. Those pressures are for the best combination of performance and comfort, so if you're encountering a lot of potholes, railroad crossings, etc. increasing the pressure even greater could lend toward protecting the rim.

ericthered

Or over inflated, or the gauge be wrong, etc. Glad you agree 85 psi is close to the right pressure for a 32mm tire. Which is what I run. The Schwalbe marathons Plus i run seem to be true to size per my measurement. I enjoyed the linked article. Your are correct that you need higher pressures for greater weights. More notable is the fact that I have not had issues since ditching the deep V's given the none scientific inflator that I am. None of this addresses the OP question of which is the strongest RR rim. If you assume I under inflate, that only makes my suggestion that the a719's are "stronger" (whatever that means). A more interesting discourse, and one not mentioned in the article, might be that the narrow rim of the deep V might narrow the tire requiring higher inflation versus a wider rim that might spread the tire and contact patch. I really do not know anything about that though wider rims seem to be returning to popularity.
Cheers
Eric

PS I ride naked so take a 1/2 pound off your calculation.

bigfred 

At this point the OP is pretty content with the idea that there isn't a "thrid" rim out there that I should really be considering but was unaware of.(for my intended use)

ericthered

One last comment from digesting the inflation discussion is the limitation of the deep V for wider tirers. 32mm is the max Velocity recommends. There was a discussion of this here:
https://www.bikeforums.net/showthread...eep-V-vs.-Dyad

Good luck on what ever you decide to use.

Eric

ericthered

Sorry, 35mm found the email:
(but that is much greater than what Sheldon recommends:https://sheldonbrown.com/tire-sizing.html near bottom chart)
Eric

Hey Eric,



Thanks for your interest in Velocity.



Inside width – tire size



Deep V: 13.5mm - 19-35mm

Aerohead: 14mm - 20 – 35mm

Synergy: 17mm - 24 – 38mm





Let me know if you have any other questions or product recommendations.



Cheers,



MD

Sales/Marketing

Velocity USA

800.453.6126

md@velocityusa.com

gyozadude

Just an FYI, I commute half the time on 32.5mm actual width (700x32C) Michelin Dynamics (the old ones before they replaced them with Dynamic "Sport"). The max side wall pressure says something like 57 psi. The Michelin Dynamic 700x28C says 87 psi on the side wall. I pump of the tires to roughly 65 psi and 95 psi respectively. Haven't ever had a pinch flat and probably because I do bunny hop and ride lightly on the saddle. But I also have a rack on the back and haul gear that stays over the rear wheel and doesn't hop lightly over bumps. That said, when it comes to wheels, I'm a strong believer in riding lightly, and also a strong believer building them myself. And that seems to allow me to ride relatively carefree and I'm well over 220 lbs.

cyccommute 

What you missed in Sheldon's discussion is this

For example: Even as a heavyweight rider, I'd wouldn't run a tire at 130psi like Sheldon suggests for 20mm wide tires. I'd actually tighten up the pressure range on all the tires. For example, I'd run a 37mm tire at around 80 psi and a 20mm tire around 115 to 120 psi. A 37mm tire is a 1.5" tire which, in the grand scheme of things isn't all that wide. On a mountain bike, I run 2.2" (55mm) tires at 45 psi in off-road situations but that's because there's a balance between rim protection and pinch flats. I also ride much, much lighter off-road...even with full suspension.

Eyelets make very little difference. They are nice but not totally necessary. I've built dozens of wheels with and without them. I've never noticed a differences in longevity.

Width also means little. I ride mountain bike wheels with the above 2.2" tires on 17mm wide rims. A wider rim is just heavier. It's not necessarily stronger.

The only rim material that would be more resistant to denting is a steel rim. Aluminum is basically aluminum. All the different alloys have about the same properties and about the same strengths...within a rather narrow range. But I wouldn't use a steel rim for several reasons including weight and poor wet weather braking.

I think you missed my point on road hazards. You don't have to dodge all of them...although you should dodge what you can. If you can't dodge them, can unweight even in traffic. All that takes is you standing up on the pedals. You can even hop the bike over stuff or, at the very least, lift the rear wheel so it doesn't slam into the obstacle as hard. Unweighting the bike and letting your body absorb the shocks even improves your control.

As I've said in numerous locations on this forum, strength of the wheel doesn't lie in the rim. The rim is a convenient place to attach a tire. The strength of the wheel is in the spokes. Your problem and comment, i.e. that you "dented" a rim, has little to do with wheel strength anyway. Strength is a longevity issue. Denting a rim is an operational issue. You build a strong wheel by choosing, in order, good spokes, a good hub and (a distant 3rd) rims. You maintain a good wheel by choosing proper tires and inflating them so as to keep the rims from being dented.

bigfred 

And, on this point, some will continue to disagree with you. State it as often as you like and in as many locations. You'll never convince those individuals that subscribe to the points made by folks like Park Tool:

"The recommended tension for spokes in bicycle wheels can be as low as 80 Kilograms force (Kfg) and as high as 230 Kilograms force. As a rule of thumb, it is best to set tension as high as the weakest link in the system will allow, which for a bicycle wheel is usually the rim. Therefore, to obtain a spoke tension recommendation for a specific wheel, it is best to contact the rim manufacturer."

The facts are: Heavy spokes allow higher tensions. Heavy spokes and higher tensions result in less elastic elongation. Less elastic elongation results in less lateral and radial flex of the rim. Lighter/weaker rims can't tolerate the high tensions that can be achieved with heavy spokes and provide less static resistance to radial flex. Heavy/stronger rims provide both more static resistance to radial flex and the ability to accomodate the higher spoke tension that heavier spokes are capable of maintaining. Hence, heavier/stronger rims can and do build into stronger wheels than lighter/weaker rims built up with the same hubs and spokes.

cyccommute 

Heavier spokes do allow for slightly more tension but that's not the reason that heavier spokes are used. Heavier spokes resist fatigue at the head of the spoke which is where a spoke is going to fail in almost all cases. Spokes are butted to get more strength a the head of the spoke where it is needed. The amount of tension that you can put on a rim with the spokes isn't limited by the spoke diameter. You can put enough tension on a 1.8mm unbutted spoke to pull the spoke through any aluminum rim before the spoke would fail.

Think of what people talk about when a wheel is failing. The number of questions that have been posted on these forums over the years about wheel failures is almost countless. Very, very few of them are about the rim failing. The typical question usually goes something like "I've broken x number of spokes, should I replace the wheels?" or the advice is usually "If you've broken x number of spokes, you should consider a wheel replacement." Also think about what advice you receive (or give) if someone wants a stronger wheel. Do you suggest a stronger rim or more spokes? I've never seen anyone suggest fewer spokes and a "stronger" rim. Almost all the advice is for more spokes.

Here's an example: Let's choose the strongest rim I can think of...a steel 1.5" balloon tire rim off a cruiser. Now let's choose the lightest weight steel spokes I can think of...DT Competitions that are 1.8/1.7/1.8mm. I'll only consider the rear wheel since that's the one that always has problems. I'll use a 130mm 10 speed hub and build the wheel in a radial nondrive/2 cross drive side pattern. And I'm going to use only 12 spokes. Is the wheel strong enough for a clyde? Would you want to ride it? It's got the most incredibly strong rim on the planet. Or would the wheel be much better with 36 spokes in the same pattern?

The aluminum of the rim is a weak link but, for the most part, wider, heavier rims are just wider and heavier. They aren't necessarily stronger because, in the end, spoke breakage is the deciding factor on wheel strength.

gyozadude

Park's website isn't always accurate. The weakest point is NOT the rim. It's the spoke elbow and Park should fix that statement. The rim is protected by tire, tube, and sometimes eyelets to distribute load. The weakest link is usually the spokes and that's the most common mode of failure.

From my experience, many folks claim their wheels failed and were looking for one rim or another. But in fact, the spokes failed and that led to catastrophic rim failure. Note that to support greater weight, all the wheel builders don't say to go with a different rim. They first tell folks to stop using 24 and 28 spoke rims and go to 32h or 36H or even 40H rims. More holes drilled for eyelets into the rim, but why is it the first choice for wheelbuilders for say heavier riders or tandem riders? Why?

Because the assertion that Park tool's site is saying that stronger spoke tension depends on the "weakest link which is the rim" and therefore contact the manufacturer, is silly. Park sells a tensiometer. They did not say it makes a strong rim. Only they recommend that spokes are pre-tensioned to as tight as the rim and rim-eyelets if the rim has them, will allow. And that's BECAUSE they know that the main failure mode is the reversal of tensile stress on the head of the spoke if the tension in the rim generated by the spokes is insufficient to always bias the spoke tension positively. In other words, if the load is heavy and it can cause the spokes at the bottom or sides of the wheel to unwind to the point where the spokes are loose and not under tension anymore, this is bad and causes fatigue on the spoke as opposed to elastic stretch if the spoke is always tight enough and under some amount of positive tension. And hence why many of the longest and strongest wheels are built with skinny in the middle butted spokes that stretch elastically.

bigfred 

Please guys, go (re)read the first chapter of The Bicycle Wheel.

cyccommute 

Never read the book. But I do have 25+ years experience building wheels and 30+ years experience of riding and observing wheels. I've had my share of failed wheels, failed spokes and failed rims. A rim that fails isn't a failed wheel, unless you can't find a rim with the same effective rim diameter. It is relatively easy to detension an existing rim, swap the spokes to a new rim and retension the wheel to have a perfectly serviceable wheel. I've done it many, many times... such as, for example, in the case of a dented rim like ericthered's. If the rim were the weakest link in the wheel system, a broken rim should be the end of the wheel. Even pulling a spoke through the rim doesn't mean that the wheel is dead.

However, a broken spoke is usually indicative of something much more ominous and systemic. Two broken spokes is cause for concern and breaking more than 2 means that you should quite riding the wheel and rebuild it with new spokes and a better technique.

I ride narrow lightweight rims on mountain bikes and road bikes. I'm never concerned that a lightweight rim might fail. I don't, however, ride wheels with low spoke counts because I know what happens to low spoke count wheels when used for heavy riders.

jr59

I ride 32 deep V's @ 260 or so with no trouble at all. Many, many miles!
I have also had great luck with the dyad rims, very strong.

I also ran a Phil Wood built 40 spoke dyad rim on my city bike. That thing is bomb proof, but free wheel only.

LVRider

I have Velocity Razors, 28 hole front/32 rear. They've held up great for me with no problems.

bigfred 

[QUOTE=cyccommute;13950753]Never read the book.
QUOTE]

You really should. Or, at least the first two chapters. Chapter One is only 40 or so pages long. Its available as a pdf on the net if you can be bothered to search for it. I think it would lend clarity to your many years of experience and the relationships between: strength vs durability, rim deformation leading to spoke fatigue, fatigue leading to breakage, rim depth and width's inpact of stiffness, etc.

Its worth your time to read.

catmandew52

Check out tandem wheel/rim combos. My former (car free) neighbor was a clyde and taco'd rims/broken spokes were a weekly occurence for him.
Most of us carry a spare tube. He carried a spare wheel.
I finally had him call Will at NYCBikes and he got a set of tandem wheels built.
They carried him all the way to Utah, from Michigan, (heading to California) before his bike was stolen.

Tandem wheel stuff. https://www.peterwhitecycles.com/Tandemparts.asp


The Bicycle Wheel book can be found here. https://icelord.net/bike/

Mr. Beanz

I'm thinking we have too many wheel threads.

Zorba

Salsa Gordo. Nothing else even comes close!

bigfred 

No such thing! Not in the Clyde forum:-) And, there are more on the way. My first wheel rebuild is on the bike right now. Photos, in their own thread, to follow. And,...I just ordered the hubs and rims for the next build last night. Sounds like the opportunity for even another clyde wheel thread.

Wheels, wheels, wheels,...:-) Its all about wheels. At least in my house it is. Thank god I prepared Mrs. Fred for this, before I started training. I told her it was going to get expensive and frustrating. This isn't the first time I've been through this. In my early teens I trained to point of being able to finish junior races in the pack and then started breaking everything on the bike. The wonderful shop owner that supported juniors like myself finally looked at the Fred parents and said, "Fred's just not built to be a bike racer." I did it again in my early twenties. I wasn't training for anything. But, was living in Jackson Hole and either cycling, hiking or skinning up mountains almost every single day. Was breaking an mtb frame per season for a few seasons before I dialed back and just returned to cycling for fun.

When I try to go fast things break. If I 'catch air" in any form(ski, bike, climbing) things break. These are the facts of my life.

gyozadude

Not really. Jobst Brandt - book is held up as a bible for lots of beginners who are looking to study wheels. But in reality, he gets basic Physics sometimes wrong. The load zone is distributed to more than the single group of 4 spokes. It is a distribution. What he often repeats as "insignificant" change in spoke tension is due to his inability to measure the tension with accuracy.

Why? Because if you're a clyde and put 100 lbs of load on 36 spokes on the front, and 240 lbs in the rear (due to panniers and loaded gear), those spokes have to change tension to account for that load. Can't get around it. Laws of Physics. If I put load sensors on the hub axles, that's what they'd register. For each spoke, that might be just 0 - 10lbs each that's pre-tensioned to 200 lbs of tension each, but over 36 spokes, that's a shift with some spokes picking up 2% change and some changing some more.

And then there's the inconsistency in Brandt's books. He says that you can tension a spoke to the max to build a wheel and that makes the wheel hold the most stress. Furthermore, he tells the story that the spoke can take more tension than the rim can at the point because it could crack or fail or warp. And THEREFORE the rim is the weakest part of the wheel.

Ah hah! So all dilettantes read that and assume that the rim is the weakest thing. But how quickly and seemingly non-sequitur, Mr. Brandt mentions off hand that, IN PRACTICE, spokes are tensioned to only about a 1/3rd of maximum rim strength. He attributes this to possible torsion failure or non-lubed spoke nipples or some other thing. And he mentions further that builders need to be careful because it is possible to over tighten a spoke and pull it through the rim or warp the rim if the nipples are lubed.

Well, having years of building experience, I have yet to see a competent (human) builder cause spoke pull through even with lubed nipple threads because we never just tighten two spokes on opposite sides of the rim. We slowly go around and tighten spokes a bit each time. Even the section of the book talking about hub flange - spoke bend contact and direct line to the spoke hole in the rim are all non-issues for hand built wheels. It's as if he's writing the manual for guys building dumb machines that want to spoke just 32 holes and tighten the rim nipples just once.

That's not to say that most of what Jobst says is wrong. He's generally right. He does say is that tires affect stiffness. Rims in the whole scheme of things are NOT the cause of most failures. And he says it's spoke fatigue and pre-stress and not letting the spokes come loose that allows spokes to survive longer and the cause of long term wheel failure. And he basically confirms what all of us builders already know. More spokes means more distribution of stress, less stress and fatigue per spoke and therefore, longer life.

And in experience, unless you're riding and falling into grates daily, or hitting boulders and putting side load on the wheel, the number one mode of failure is fatigue leading to spoke breakage. And that's where having any decent rim with more spokes will help.

In the future, rather than just point to someone's book, why not cut/paste and cite actually what it says, or what you interpret it to mean in the context of how you read it. It doesn't help advance the discussion to tell someone to read the book. I know lots of competent wheel builders who make great wheels who never needed to read Jobst Brandt. As a scientist, engineer, AND mechanic (and I wasn't a software engineer for all of my career), I will put my bet on someone who DOES in reality and their experience far MORE than someone who has a book out. Anyone can research and write a book and do some experiments in a lab. Only until their theories are proven do I respect that, and even then, I respect the guys who build and put the stuff into practice than the folks that just sit and speculate.

And to remind myself, everytime I look at the $12 cheap Alex RP15F rims or X202 single walls that have gone a few thousand miles without failure or much tweaking at all, I wonder to myself: why do I have a huge stock of Velocity and Mavic rims hanging in the garage? I think it's about the "bling" factor more than anything else. It's maybe when folks come over with the Carbon Fibre bike and look upon my small shop, they will appreciate my prowess via the labels of my components. And then it gives my tendency to ride Real-Steel and be a retro-grouch half the time some credibility. Yeah, sure, I stock brifters too and ride them sometimes. But the having the "stuff" makes me cool.

But deep down, I can't escape the reality, that if I build a decent wheel with decent spokes, any rim can last a VERY long time regardless of price or advertised strength. My bets are on the builder and the quality of the spokes - which in PRACTICE are the weakest part of the wheel due to fatigue. The rims much less so.