Come up with a number for psi you find comfortable, and create a complicated formula to get you that result. Easy. Reverse engineering.

This is a simplified formula for the 15% drop. The original formula had a factor for the weight distribution and a lot more decimals that I removed because the precision greatly exceeded the accuracy.

I used to run the front tire lower pressure than the rear, then I pinch flatted the front a couple of times, so I now run them pretty close to the same.

How great an effect do you expect from the bracing angle? How much of a difference is a “huge” difference? Using this calculator using a White Industries MI5 hub and Velocity Dyad in 559mm and 622mm rims, the bracing angles are 8.3°/5° (R/L) for the 559 and 7.4°/4.4°. How much of a difference is significant?

On the other hand, if you built the wheels with a Velocity A23 OC hub, the bracing angle would be 6.6°/5.1° which is a smaller bracing angle but it’s more equivalent and makes for a more durable wheel.

So the spoke density is unimportant and the spoke tension is unimportant so what is “important”? The bracing angle?

Your ruler analogy is apt. Most of the high profile rims also tend to be rather thin. Your ruler may not bend easily when you push down on it but if you push on it laterally, it bend rather easily. Wheels don’t just work in one direction. Yes they are stiffer but only from in one direction.


Yea, I “think”. The reason that the Tioga was not such a great wheel is that it depended on the plastic disc for rigidity. Remove the disc and there is nothing there for rigidity. The wheel might be capable of vertical rigidity but the first time you put a lateral load on the rim and the whole thing is going to collapse. Again, the spokes do the work.

Yes, it’s a silly bike but that would be the only way to build with a rim of rubber...by using spokes in compression. But you can’t build with only either. The string would not have any lateral stiffness which is necessary to hold the rim in place. It wouldn’t matter how much tension you put on the strings, without something...like the Tioga’s disc...for them to pull against, the whole thing would fall over.

But a very important part of the puzzle. Look at it this way, you could get a steel rim which is the stiffest, strongest rim available. Now pair it with weak spokes like, for example, 1.5mm spokes and built it properly. I doubt that you would end up with a wheel that would be sufficient for a touring load. It would pop spokes more than your local multiplex theater.

Alternatively, lower the number of spoke to a ridiculous number...let’s say 8 paired spoke...and, just to make the test less fair, let’s use those 1.5mm spokes. Would you ride that steel rimmed wheel on a loaded touring bike down a mountain at 50 mph? I wouldn’t ride that wheel across the street.


What about it “doesn’t work”? I’ve been building with triple butted spokes for the better part of 20 years. Broken spokes are a thing of the past for me. My first build with triple butted spokes was a mountain bike wheel that was ridden hard off-road for 15 years. The only reason that I had to replace the wheel is because I loaned the bike out and the guy overshifted into the spokes...he “adjusted” the derailer because it wasn’t shifting properly (to him) in the manner that most people “adjust” derailers by messing with the limit screws.

My wheels are “sensible”...and strong...and durable. And my wheels are all built with an eye to “component choice, compatibity, build quality” and how the wheel is going to be used. Give me some credit for have a little intelligence. I haven’t found a situation yet where having a heavier rim than what I normally use would be advantageous. If the spokes don’t break and the wheel stays true and round, what more do you think I could do to make the wheel “better”?

As an example of my choices on wheel builds, I built wheels for my fast bike to replace supposedly “better” low spoke count wheels. I used Velocity A23 (not super light rim but it’s not a heavy rim either), Pillar triple butted spokes, White Industry T11 hubs and splined nipples. Do you see anything wrong with those choices? I certainly didn’t and, as an added bonus, the bike went from weighing 22 lbs (10 kg for those with a proper measurement system) to weighing 20 lbs (9 kg) with a what I would consider a far stronger wheel. I’ll take a loss of a kilo of weight off a bike any time and a loss of a kilo of rotating weight is something everyone strives for.

It's hard to say exactly how much is significant without doing some extensive testing. But what is clear is that the bracing angle difference is significant which in turn means that the wheel is much more resistant to sideways loading. What did not surprise me was that the spoke tension difference does not change between sides, because why would it? The angle ratios remain the same.

Now while this is something I would absolutely advocate (since OC rims do make wheels strongers as a component choice), isn't this kinda going outside the goalposts?
Also the funny thing about OC rims is that they rely heavily on the rim stiffness charasteristics to work. If your rim had very little torsional stiffness i'd suspect it would not work at all as an OC rim. Which then brings us back to rim stiffness in general.



I see you've stooped to putting word in my mouth. As some would say: "not cool man!".
As you should know as a fellow wheelbuilder, it all contributes. Every aspect has an effect and maximizing the durability enhancing sides of those aspects is what builds a strong wheel. Neglect one aspect and the wheel won't implode, but it will be somewhat weaker as a result. Not everyone wants to ride 26" wheels (me being one of them) and so they have to take the durability loss of that aspect. There are also those who prefer a low number of spokes and also prefer them to be extra light. It's all about the compromises you're willing to accept.

Hence why it's important that the rim is stiff vertically (and as I realized above, also torsionally). Lateral stiffness isn't as important, because that is where the spokes actually do help with the failings of the rim. Lateral stiffness is largely due to the contribution of spokes in both the stiffness as a whole but also in point stiffness (where you would try to bend the wheel in or out in a single point). On the other hand, while spokes are largely responsible for the vertical stiffness of the wheel as a whole they do not contribute at all to vertical point stiffness (such as when the the force inflicted upon the ground is countered by the ground itself and... Man explaining physics simply is kinda tough isn't it. Let's just say the point stiffness counts where the ground is pushing against the wheel)

BUT it needs to be added that IMO the best touring rims are Vee/box section hybrids where you get the vertical stiffness of the high vertical walls as well as the high Vee-section but also the lateral stiffness of the lateral walls present in the rim. Hence, box section. Double wall.

But tension is the only think that keeps the wheel from coming apart. There is NO compression in spokes, they cannot handle it. Spokes do have some rigidity, but again it's not compression that's keeping the wheel from coming apart. I also disagree with the notion that the wheel would just fall over. If you do 3X you'd have tension pulling both forwards and back but with the bracing angles also to the sides which would mean the wheel would at least stand. Whether it'd be rideable with conventional bike components.. Well I don't know about that.

But you can't save a bad build with good spokes. The good spokes will be just as prone to failure as the bad spokes if there is a critical compromising factor in the wheelbuild. Granted the Alpine III's are the best out there and those are what I use for my heavy duty wheels, but the 1.5mm double butteds' from DT Swiss aren't exactly bad either. I'm pretty sure you could build a successful touring wheel out of them if you beefed up the other factors, ie. more spokes, smaller wheel diameter, stiffer rim etc etc etc. But no, they aren't good if you're trying to maximize strength and durability. Nor would it be exactly smart to build a touring wheel with such light spokes because the extra spokes aspect would just eat all the weight savings...

As for lowering the number of spokes to ridiculously low. No, I would not ride that wheel if it had a steel rim. A flexy steel rim would not be able to support the wheel with so few spokes. If it had a really high profile carbon rim reinforced to allow for really high tensions and I'd be allowed to build said wheel I'd use it without load. But since I'm myself pretty heavy that'd be pushing it. But even with a stiff rim, too little spokes causes too much point load (or is it point slack...) to one spoke.

Sorry but you can’t have it both ways. You can’t say that it hard to say how significant bracing angle differences are and say that bracing angle differences are significant on a 1° level. I’m not saying that the difference isn’t significant only that I don’t know how large a difference is significant.

It’s not moving the goal posts at all. It kind of shows how the bracing angle is somewhat insignificant without taking other factors into account.

I also don’t agree that OC rims are any stiffer than a comparable centerline drilled rim. The A23 OC and the A23 are similarly constructed. The advantage of the OC for a dished wheel comes from the more closely equalized spoke tension. Do an apples to apples comparison rather than cheese to chalk one.


I didn’t put words in your mouth at all. You are the one who said something is important and then said it isn’t. Yes, I agree that all aspects contribute but some contribute more than others. Nearly every discussion I’ve had about wheels starts with the person looking for a strong rim. The discussion usually ends there too. Yes, rims are important but they aren’t the most important element of the wheel. That’s my point. Most any rim you want to choose is going to work. Not every spoke you choose is going to do the job. Would you honestly ride my steel wheel example above? Although it is an extreme, it’s very similar to what most people think is a “strong” wheel.

Lateral stiffness is the most important parameter. You could build your string wheel and, like I said above, it would probably stand up. Put a lateral load on it and rim will do nothing to stop the wheel from folding over.

Also remember that every time any rim hits the bottom of rotation that it is deflected upwards. Making it stiffer decreases the upward deflection but it will still deflect because, as you pointed out, the wheel is in tension and there is nothing to keep the rim from deflecting.



A string spoked wheel would depend entirely on the rim rigidity. Lace up a set of wheels loosely and go for a ride. The wheel snakebellies as it goes down the road. Loose spoke have just enough rigidity to keep the wheel from folding but only just. Even the vertical rigidity is poor because the rim isn’t under enough tension for the load to be spread around.


But you can’t save a bad build with a stronger rim. That’s my point. Yes, it all works together but you can only beef up the other factors so much. There are limits. And, for each of those parameters that you want to beef up, going with a stronger spoke is going to make them more beefy. I’m not saying, nor have I ever said, to build with poor components.​​ Build with good components but don’t put too much emphasis on parts that don’t have that much of an effect on durability and strength.​​​

​I think you are missing why I choose a steel rim. A steel rim is far from “flexible”. Aluminum is flexible. Steel is 3 times stiffer and a steel rim doesn’t lose that stiffness. My point for choosing a steel rim is that it is stiff, strong and inflexible. It is the ultimate in a “strong” rim. I wouldn’t ride a low spoke steel wheel with light spokes because the spokes would be very prone to breaking. I don’t ride low spoke count wheels for the same reason. I don’t buy into the “the rims are really strong so the wheel is strong” sales pitch. Apparently neither do you.

My overall point is that people look at a wheel and they see a hub and a rim and that’s all. The spokes are invisible and an afterthought...until the spokes start to break. Then they start looking around for a stronger rim to solve the problem. It’s not the problem they need to solve. More spokes works but stronger spokes works better. Most any rim made in the last 20 years is strong enough for the job. I start every wheel build with the spokes, then I worry about what hub to use and the rim is the last thing I consider and then only is terms of weight.

I need to revisit what I wrote there. I have the flu so I'm not exactly firing with all cylinders at the moment.



That's actually the whole point of this whole discussion. Everything matters. What matters most seems the be the argument.

They actually probably aren't any stiffer than the center drilled ones when we're considering the same model. But they do need some significant torsional stiffness so that the rim doesn't bend to one side when riding.


At best you're interpreting my comments in the least favourable way instead of trying to see the whole point I'm trying to convey. Back there you just grabbed on to some tidbits which were insignificant in terms of the whole comment, and when I respond that that things wasn't actually the whole point this happens.



And lateral stiffness is achieved via the spokes, not the rim. So rim lateral stiffness doesn't really matter all that much. But in box section rims it's still there usually.

I feel like you're maybe starting to get my point. If the rim is flexy enough to allow for the actual rim to deflect it will allow for the spokes to go slack. If the rim is stiff enough that so that it keeps its shape, the actual wheel will need to deflect enough for the spokes to go slack. There's a big difference here. Does the wheel deflect, or does the rim deflect? If the rim is stiff enough vertically the deflection will need to overcome the wheel spoke tension. If the rim is not stiff enough the spoke tension won't matter nearly as much as the rim will push inward none the less.

I'm having trouble understanding how these two things coincide. If the string wheel is tensioned to high enough a tension it should not resemble a loose wheel. In fact when riding completely upright it should resemble a normal wheel almost perfectly. However the lateral stiffness may be an issue. But I need to check that whether that's true or not.


But you're not getting what I'm trying to say. If the rim is flexy enough that the rim itself deflects on when against the ground no amount of spoke beefiness will save the wheel because it won't matter. If the spokes are allowed to go slack there's no amount of beef that will save them. However if the spokes are never allowed to go slack even for a little bit the, and I hate myself for saying this, even straight gauge cheapie spokes can do just fine. Better spokes have more resistance for the occasional hardship which is way more common in touring. But even the best spoke cannot withstand a situation where the wheel is exposed to conditions the wheel was not designed to withstand (too large a load for the rim stiffness for example)
All that being said Bontrager straight gauge spokes are made of cheese so no matter how good the build they will not last...
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Yes, steel is stiff. However shape matters more than material in terms of stiffness. Steel rims cannot be extruded in any practical manner so steel rims are limited to single wall designs with perhaps a little doubling over. But in the end they are made from folded sheet. Also to keep the weight from being prohibitively high they need to be pretty thin stuff.
On the other hand aluminum rims are extruded giving the possibility for pretty wacky shapes. Aluminum extruded in box vee hybrid with double walls and even perhaps tubeless shelves is going to be more stiff than an equivalent steel bent from sheet.
Also 3mm aluminum is stiffer than 1mm of steel even though they weigh the same. Aluminum gains stiffness from thickness (most metals do I think)

As for the strong rim = strong wheel. I don't buy into that either. But it is easier to build a strong wheel with a strong rim than it is with a weak rim.
I actually wouldn't have a problem using low spoke count wheels in road riding if I had owned a road bike that would benefit from such. If I ever do build myself a road bike again I'll probably build some 24/28 spoke wheels with super high carbon rims and aerodynamic spokes. But that's a project for another time.

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