There isn't much in the bicycle mythos that is more worshiped or revered than the bicycle wheel. Specifically, the traditional bicycle wheel, if you want to retain the mystical connotation. It is an under-appreciated wonder of engineering, and represents a perfect combination of simplicity, elegance, and good design. There's a lot to be said about the bicycle wheel, and this isn't a place where you'll hear a lot of it. If I were to go into a more in-depth explanation of what goes into a bicycle wheel, this would be a very long and probably somewhat boring post. Instead, I'm just going to recount my experience of my first completely solo wheel build, with nuggets of vital information.
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| Starting the wheel building process. January 9, 2013 |
I say completely solo because I had help on my first wheel build ever. A coworker in Indiana helped me plan and build a wheelset for a very awesome Schwinn racing bike from the 1970's that I briefly owned. He essentially walked me through the process of lacing the wheel, and then he wrapped it up by tensioning the spokes. We only did this for the rear wheel, for I attempted to solo the front wheel but couldn't figure out how to start the lacing. Looking back, I blame his desire to uphold a common signature of wheel building: lining up any sort of logo on the hub with the valve stem hole. It's a little tricky as typically a hub gets turned during the lacing process. He ended up building that wheel for me.
Since then I hadn't tried to build any wheels. The need, or funds, never really came up. That began to change as our bicycles re-entered our lives after moving to Tucson, Arizona. In particular I was needing to build a set of wheels for my fiancee
Keri's Motobecane. We got her bike with the stock wheels, sporting beautiful high flange hubs and--gulp--single-walled rims. Interestingly enough, the front rim is aluminum, and the rear is steel. The hubs are the same, so that leads me to believe they are the original wheels. Not sure what is going on with that.
But the problem, besides the fact that Keri was riding on inferior, ready-to-bust wheels, was that she kept getting flats. A ridiculous number of flats. As a mechanic, who has to change numerous tubes a day, I am typically pretty unsympathetic about this sort of thing. Getting a flat is part of riding a bike, plain and simple. But Keri was having serious trouble, especially from her rims. Now, a bit of bicycle knowledge.
Between single-walled rims and double-walled rims, there is no contest. Single-walled rims are significantly weaker, more prone to going out of true, and their only positive quality is that they are the cheaper alternative. Double-walled rims are more or less the norm on any bike past the $500 mark, and as my former manager would always say, "No bike mechanic would build himself a wheel without a double-walled rim." They are much stronger, add very little weight, and the price jump is honestly not that bad. What you gain in integrity far outpaces the price jump.
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Left: Single-walled rim. Note the upside-down U shape of the rim. Source
Right: Double-walled rim. Note the second wall, adding a dramatic amount of strength. Source |
Rim tape, which is used on double-walled rims to protect the tube from blowing out on the milled nipple holes, is tougher than rim strips, which are essentially giant rubber bands. The rubber rim strips were not covering up all of the little holes that tend to line the inside edges of steel rims either, and I am certain those were causing trouble for her too. So, I decided to kill two birds with one stone and work on upgrading her wheels entirely.
One of my greatest hang ups when picking out components for a wheel is the hub. I have a great affection for vintage hub designs, specifically high flanges and narrow hub shell. Some of the most beautiful hubs, in my opinion, have a deep yet gentle concave profile. They're hard to come by, and nowadays they only exist as track hubs, although I'll admit I don't find many modern track hubs very keen to look at. More typical road hubs simply don't follow the aesthetic of their predecessors, they tend to have low flanges and thick hub shells, with hard angles connecting the two. Not there is anything specifically wrong with this style, I just prefer the older look. I've spent a lot of time looking at hubs, trying to find ones I liked. Then one day, I realized how silly I was being. I could just use the hubs that came with her bike!
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Left: Nasty side shot of the hub.
Right: Stamped name on the hub shell, reads "NORMANDY FRANCE".
Both taken November 29, 2012 |
They are, from the best that I can tell, the stock hubs that would have come on the bike. Normandy hubs, made in France. Aluminum, thirty-six holes and overall a nice design. Not my favorite, but a nice look. They resemble a pair of Campagnolo hubs I have laced to a set of vintage wheels hanging on my wall. I started by unlacing the front wheel. After that, I took the hub in with me to work and disassembled it to clean and repack everything. I have an ultrasonic parts cleaner at my disposal there, and that did a good job of removing a lot of the grim and crud. A lot of the tarnish still persisted, however, so I had to use another trick. A Google search unveiled a relatively simple procedure using
Brillo pads and elbow grease to clean up aluminium. Filling the kitchen sink with warm water, I scrubbed away. All-in-all it worked rather well, considering I only spent a few bucks on a box full of Brillo pads. The site that offered the Brillo trick also suggested rubbing a ball of aluminium foil onto the object to shine it up, but this did not yield any favorable results for me. This is probably because there aren't many flat surfaces on the hub. But maybe I was just doing it wrong.
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Look at how shiny and clean it turned out! Note: The golden yellow tone
comes from the poor lighting of my living room. December 1, 2012 |
While disassembling the hub, I accidentally botched up the axle. Old axles tend to have a shallow groove cut along the length of the axle, for keyed washers that lie between the cone and lock nut. The same thing tends to exist more commonly on threaded headsets. And just like on the threaded headsets, these keyed washers tend to turn in place and lodge their key in the threads. If you're careful you can usually work the washer back to where the key lines up with the key slot, but if you're not careful you can booger up the threads. This is what I ended up doing to the original axle. I decided on replacing it with a modern axle, which isn't that big of a deal. There isn't much that is special about axles, at least to me.
With the hub finished up, I was able to make all of the necessary measurements to calculate spoke length. There is some fancy math you can use to do this (I don't know it) but nowadays there are a plethora of online spoke length calculators. I used the
United Bicycle Institute's calculator. 296mm spokes were what came out for me, for a three-cross front wheel. Time for some more explanation.
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An example of a spoke on a three cross wheel. Each arrow points to a
point where the highlighted spoke is crossing another spoke. January 14, 2013 |
The lacing of the spokes of a bicycle wheel is just one of the several ways to categorize wheels. The United Bicycle Institute's calculator goes up to five-cross, so I guess you can say you can go from zero to five. The term " # cross" signifies how many other spokes a single spoke will bisect. On a three-cross wheel, every spoke crosses three other spokes. On a four-cross wheel, every spoke crosses four other spokes. This design is a simple yet extremely effective way of building strength--through tangents, much like a
truss bridge--into a bicycle wheel in a lightweight manner. Typically the more spokes a single spoke crosses, the stronger the wheel. This adds weight of course (due to longer spokes) but the increase in weight is not a tremendous thing. Three-cross wheels are considered the "norm", although this is slowly disappearing. I chose to lace Keri's wheel in three-cross mostly because I've found they are easy to replace spokes in. I've had to replace spokes in four-cross wheels and I found it frustrating sliding the spoke into place.
The spokes I used were cheaper, relatively simple spokes. The problem is that spokes can be very expensive, and can be just as "high tech" as the hubs or rims. I went with Wheel Master straight gauge stainless steel spokes. A box of seventy-five spokes retails for $30, and although I don't need seventy-five, it ended up being my cheapest option. For a little more money, I could have gone with some DT Swiss double-butted spokes, which would be stronger and lighter, but it would have been a hassle. I figure this wheel will be a good preliminary build for Keri, if she gets more serious we can bust out the big bucks when the time comes.
The final component is the rim, and an important one it is! There aren't many 27" rim options out there anymore. The only two viable options I had were Sun or Weinmann rims. I decided to stay away from Weinmann. They don't really make a bad product but they are sort of synonymous with cheap in wheels. Sun, on the other hand, makes some nice yet affordable rims, and I've actually had experience with them. I own a pair of pre-built wheels with Sun M-13II rims that are currently on my Fuji or Cannondale (I have to swap between bikes depending on what I want to ride.) They look great and have held up well for over a year now. I could have gotten another M-13II rim but I figured I already know how it holds up, so I'll experiment and try the Sun CR-18. It is a little more wide but also appears to be a little more sturdy. In addition, the 27" CR-18 comes polished. Pretty!
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| A Christmas gift from Keri, which I used to build her wheel! Source |
With all of the parts finally in my possession, I could begin the wheel building process. Luckily I had just received the book "
Zinn & the Art of Road Bike Maintenance" from Keri for Christmas, and it has a step-by-step procedure for building a three-cross wheel. I then proceeded to sit on my living room floor and anxiously began the lacing process.
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Beginning of the lacing process. Sun CR-18 rim, Zinn's book, Normandy hub,
36 nipples and spokes, spoke wrench and slotted screwdriver. January 9, 2013 |
I won't go into any real detail on the lacing process, as it would balloon the size of the post and isn't that relevant. To sum it up, I began by lacing half of the spokes for one flange to the rim, and then laced half of the spokes for the opposite flange.
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| A quarter of the spokes laced, another quarter ready to be laced. January 9, 2013 |
Then I spun the hub as far as I could and began truly lacing the third quarter of spokes. I say truly because it was at this point that I started crossing spokes and, in a sense, weaving them to create a strong wheel. After the last two quarters of spokes were done, I had an untensioned, yet fully laced, bicycle wheel. What an accomplishment it felt like! But the hardest part was about to happen, the tensioning.
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Three quarters of the spokes are laced. Note how it is beginning to
resemble a normal wheel. January 9, 2013 |
Naturally, after lacing a wheel you have to bring all of the spokes up to proper tension. A poorly tensioned wheel won't last as long as a properly done one, and tensioning can be a tricky process. I did some preliminary tensioning at home, by tightening every spoke until I knew I was in the ball-park. But I had to eventually take it into work with me to use a proper truing stand. I attempted to use a bike and it's fork flipped upside down, but that only helped me get into the ballpark. It didn't quite provide me with the precision I was needing. In addition to tensioning the spokes I have to of course maintain lateral trueness--that's the elimination of side-to-side wobble--and radial trueness--making sure the rim is a perfect circle and not lopsided. There is also the dish of the wheel to consider, which essentially means whether or not the rim is in the center of the fork or frame when the wheel is mounted. Balancing all of these attributes while making sure the spokes are at a proper tension can be harrowing on the mind, especially when dealing with thirty-six of them! Eventually I managed to get the wheel within sufficient tolerances. No wheel is truly perfect, simply because there are too many elements pushing and pulling against others. You could make a perfectly true wheel, but it may not be uniformly tensioned. Likewise, a uniformly tensioned wheel more than likely wouldn't be perfectly true. You have to reach a state of balance between all of these parameters in order to build a good wheel. There is some serious Taoism going on in wheel building.
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Finished wheel. Note the rings of reflected light on the
floor and walls. Shiny! January 14, 2013 |
With the wheel ready, I applied the rim tape, installed the tire and tube, and mounted the wheel in the Motobecane's fork. Needless to say, it all looks great. Can't wait to start on the rear wheel.
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| Final product. January 14, 2013 |
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