Myths About Wheel Building

By Rob Curtis (aka PSIMET)

The internet is a great invention. It allows us to access information so readily it can truly make your head spin. Turns out it also provides immediate access to information regardless of its validity. As a wheelbuilder this situation can really be a pain. Like with all hobbies or interests there is a large number of internet thugs that are positive they are the only ones who possess the correct information to what things are right or how they should be done. These people pollute the inturnetz with pages filled with what can only be described as old wives tales. Today I would like to take some of these common misconceptions about wheels and wheel builds on. No doubt some will take issue with what I am posting here but at least you’ll know where we stand.

1. Wheelbuilding is just quite simply assembling the components of the wheel. It’s a process that anyone can learn and any shop anywhere can do it well. It’s not a craft and there’s nothing special to it.

It has taken me a lot of time in reflection on this one to assemble how I feel about it. I’m not one to think that there is anything particularly mystic about me or what I do and yet I know from cold hard experience that the wheels I build are often completely different than those built by others even when we use the same materials. The closest analogy that seems to make this 100% clear to people is bicycle frame building.

“Building a frame is simply the assembly of tubes into a frame. If you all have the raw materials and the tools then if you’ve been shown the process then anyone can do it and there is nothing special about it. All frames are the same.” See how stupid that sounds when you say it?

Can machines build bicycle frames? Yes. Can just about any bike nerd in any shop in the country be taught to assemble frame tubes into a bicycle shaped object? Yes. Is a Mongoose POS bought from a big box store the same as a frame built by Richard Sachs? No. We all know this to be true and yet somehow we forget this when it comes to wheels. We view wheels more like slapping components on a frame than we do actually creating a tensioned unit that has integrated mechanical connections that allow it to function as a single entity….more like a frame.

Quite simply if you give 6 wheel builders – people who claim they can all build wheels – the same kits of components to build a wheelset from you will get 6 different wheels. It’s a constant challenge to articulate and express this though. I vividly remember one discussion with a local shop owner. I was expressing how there was no way we should ever think of ourselves as competitors: I didn’t sell bikes – I was a wheelbuilder. That’s when he said, “see Rob that’s where I have a problem – I’m a wheelbuilder too.”

I know about 4 people he has built wheels for and they all have either fallen apart or just been scrapped completely. Did he know how to assemble all of the parts into a wheel shaped object? Sure. Was he a wheelbuilder? No. It is for this reason that I still contend that even if you work in a shop and build “a lot” of wheels you are still not a wheelbuilder per se. A chef can bake cupcakes but that doesn’t make them a baker. Period…errr…ATMO

2. “I use thinner spokes on the non-drive side so that I can run it at higher tensions and get a better tension balance.”

Someone in some shop somewhere told these people this crap. Most likely over a cup of coffee. You can read more about spokes in general in my post on the subject but in general spokes are simply tension carrying elements. That just means that the diameter of them plays no role in the their “tension”. Tension is tension. If you pull hard at an angle – Newton says you have to pull at the same in the other direction in order to be equal and opposite or in static equilibrium.

Drive side pulls at the max tension. Non drive side is at a greater angle therefore it has to pull at a lower tension.

Drive side pulls at the max tension. Non drive side is at a greater angle therefore it has to pull at a lower tension.

Fig2

Fig2

If the non-drive side pulls at a lower tension then the resultant horizontal component is lower (Fig2). At about 60% then the horizontal component of the tension is the same as the drive side horizontal component. This has absolutely nothing to do with the diameter of the spoke. NewtonMeme

So putting a thinner spoke does NOT allow a higher tension in the rear wheel when used on the non-driveside. The only way to increase the NDS tension is to change the geometry. Change where the nipple bed is (asymmetrical rims) or change the flange spacing or size. Smaller diameter spokes will simply lower the weight of the wheel and usually your wallet as well.

3. Ceramic bearings are always better.

We’ve all seen the videos of awesome ceramic bearings that spin for 20 minutes after someone barely sneezes on them. Those videos are awesome—ly entertaining. Ceramic bearings CAN be awesome. The vast majority of the ones that you have the opportunity to use on your bicycle aren’t so awesome. First ceramic bearings have qualities that make them great for the applications in which they were designed. They operate well at high speeds and can withstand heat extremely well. Think motor shafts and a thousand plus degrees in temperature. Until those seatpost motors become ubiquitous I think it’s safe to safe ceramic isn’t necessarily the right bearing for cycling.

Some benefits though are great. They CAN be made more precisely than traditional bearings. They are extremely hard and more resistant to corrosion than steel or even stainless bearings are. Here’s where it gets fun though – Really precise, round ceramic bearings that are hard and durable and not prone to corrosion are bearings where the races as well as the ball elements are ceramic. Those are $$$$$. Like check out my Lambo grocery getter or Space Shuttle pricey.

In fact most of the bearings that are used specifically in wheels that call themselves ceramic are hybrid ceramic. They have steel races and ceramic ball elements. Due to costs involved a lot of times the quality of the races and the quality/roundness of the ball elements are actually a lower quality than the parts involved with constructing an ABEC 5 steel bearing. This little myth though has been evolving. The bearing manufacturers have been coming out with better and better offerings that do let us take some of the advantages of ceramic into our specific applications and offer us a benefit over high quality steel bearings.

Kogel Bearings  does a supremely good job at the complete specification and assembly of truly higher end bearings specific for the application. We do offer them – just ask if interested. Some of the products from our other bearing provider Enduro have also gotten a lot better since we first started seeing hybrid ceramic wheel bearings hit the market. So while the bearing landscape has been getting more and more complex the general myth that ceramic bearings are always an upgrade is still true…they are not.

4. Hubs are hubs. There is little to no difference between them.

The largest single expense in a wheel build is almost always the hub (not always true when we think of high end carbon). I therefore have to spent a lot of my time explaining the differences between the hubs. Because they have the most moving parts and can be made from any material from steel to yet to be discovered un-obtanium forged from unicorn tears and elf farts this is also the one place in a wheel build that a lot of brands look to save some money. Almost everyone has an inexpensive hub that they build with at a house brand level. Most of the time these hubs are standard off the shelf catalog product from one of the thousands of hub manufacturers out there. Most of these guys are based in Taiwan so we commonly refer to these as “import hubs”.

There’s nothing wrong with an import hub. Heck Chris King are import hubs to any builder outside the US. Just is what it is. Sometimes these hubs get bad reputations though. In general the inexpensive versions of import hubs tend to have a lot of the following traits in common: they have cast aluminum freehub bodies, sometimes lower quality bearings, smaller bearing elements to save weight (lowers load capacity of the hub), etc.

What many may not know is that this level of hub is used in most all premium level wheels built. Most wheel companies aren’t hub manufacturers. HED, Reynolds, ENVE, etc have often used and most continue to use common catalog or simple modification hubs from most of the same manufacturers. Zipp is one of the few companies that has been building their own hubs but to be honest I have usually despised their designs. They have had quite a few failures and recalls over the years on their hubs as well.

Nicer hubs tend to be made in smaller production environments, using better tooling, not run of the mill designs, and usually better material selections throughout. The tolerancing on the designs seem to be tighter. The control is usually better. The drive mechanisms are usually more durable and better built leading to longer life throughout. Titanium freehub bodies. Hardened and anodized aluminum. Larger bearings throughout, etc. Like a fine machine these hubs tend to wear in over time as opposed to wearing out. I will quite commonly recommend saving a used White Industries hub for a new build while generally recommend trashing an import hub for the same application.

5. Cup and cone bearings are the best and you should always build wheels with cup and cone bearings.

Cup and cone bearing systems had their day. They were awesome. So was Led Zeppelin and cassette tapes. The big thing about this older style of hub bearing system is quite simply that the bearing preload is adjustable and that they are designed to take an axial load as well as a radial load. The whole world has switched to commonly available cartridge bearings. Cartridge bearings are generally designed to take a radial load only. The fear of this axial load is what led the guys like Shimano and Campagnolo to swear off cartridge bearings in wheels. Well that was the 80’s. Mavic kicked all of their butts and did it with cartridge bearings. Turns out they work. They work well. All of the major companies that are considered boutique hubs use cartridge bearings.

In fact if you were dead set on getting cup and cone bearings we would be greatly limited on hub options. To the point where you’d most likely be stuck with a 32 or 36 spoke option only. Cartridge bearings are amazing. Can be built for tons of different applications. Are easy to replace and relatively inexpensive when compared to the cost of a whole hub. When cup and cone go bad you’re replacing the whole hub. We can sit around and talk about how great cup and cone were. We can fire up the 8-track, crack a can of Hamm’s and talk about how awesome the 80’s are going to be as well but I’d just assume run cartridge.

6. Carbon rims are all the same.

They’re not. Not even close. The resins, cure times, temperture ramps, layups, etc are all completely different. It’s like saying all cars are the same because they have doors a windshield and 4 wheels. Along these lines carbon brake pads are extremely different as well. I have found out the hard way – they all operate at different temperatures. “I have carbon pads in there” doesn’t cut it. You need the ones that were designed to work with your rims. When in doubt contact the OEM.

7. Riding carbon wheels on a trainer will damage them.

Seriously….there are people who believe this. This is so untrue it hurts. In fact wheels will definitely fare better on the trainer than they will being ridden around on roads with things like potholes …..and cat 6ers.

8. Size matters/Aero is everything

Deeper is better! Wider is better! Aero is better! That sound you hear is me beating my head against the desk. Whenever these discussions come up people just latch on to their beliefs with the fervor usually reserved for religious crusades. A lot of the discussions usually center around the trends in the industry over the last decade to go to wider rims. Reams of data have been generated by more than one groups who claim that by setting up their own study it definitely shows their rims are better because they are wider. At the same time deeper rim sections must be better too. I mean – they are aero and that’s everything. Not to mention they look kick ass.

Sure in general wider rims seem to bring out better qualities in the tires we like to use. They increase the air volume for the same size tire over a narrower rim which in turn allows you to run a lower pressure. Lower pressure on a higher air volume feels more comfortable. These are not revolutionary concepts. At the same time aero is awesome. It will allow you to gain so much time on your next 40k TT that you will hardly even have to pedal anymore. Or not.

Turns out you can achieve aero shapes that are shallower than anticipated. Also it turns out that aero data is only ever as good as the person who has commissioned it. Wind tunnel time is expensive and the constraints placed on the models are designed by the same person who has to justify their designs later. Kind of like letting the fox in the hen house.

Reality is that you can take amazingly new wheels and put them on top end racers and they will place just as well as they do with wheels they were running 4-5 years ago. The width or the aero just aren’t going to win the crit or the cross race for them. The athlete still has to perform and turns out their form will always trump the gear (LeMond’s 1989 TT Performance aside). Personally I have found through direct experience that the wheels that last and can be counted on to perform each and every time consistently always out trump whatever new technology someone wants to peddle.

To quote my favorite quote from Jacques Anquetil (happens to be on the back of my business card even) : “Strange people, bike riders. They imagine a racing bike is made for going quickly. They’re wrong. A racing bike is made solely for winning races.” In this day of saturation of technology it’s extremely valuable to remember that the fastest equipment is the equipment that gets you across the line first. Sometimes that simply means the equipment that stays together.

PSIMET
11 Jackson St E Dundee, IL - 60118
(847) 428-2600