Essential upgrades, wheels and tubes.
If you read the review of the Foundry Harrow cyclocross bike, then you know how impressed I was with it. The handling and ride qualities were fantastic for any cyclocross bike, and given the price of this bike, it is a great choice for anyone looking for a new mount. As with any stock bike, however, there is typically something that can be improved. Some upgrades can deliver large performance returns and others small. Obviously, as competitors, we want to look for large returns first.
On most stock bikes available today, the manufacturer will boast their frames and shifter/derailleur packages. In order to keep the price attractive, however, the manufacturer will often include wheels, cranks, seat post, stem and handlebars that leave a fair amount of room for improvement. These stock parts are usually adequate and durable, but for those looking for maximum performance, upgrading these components can significantly improve the bike.
Most bicycle experts would agree that the first upgrade should be the wheels. A good set of wheels can significantly improve the ride quality of a bicycle in many ways. One way is weight. Because a wheel rotates and must be accelerated, a lighter weight wheel can save you a lot of energy in a competition and will get you up to speed faster. Physics tells us that the weight of the rim, tire and tube will make a bigger difference than the weight of the hubs. What some may not know, however, is that rim and inner tube choice can also improve the performance of your tires.
In this review we will highlight the latest developments in rim technology and how this affects our tire’s grip and performance. We will also look at latex inner tubes and how they can further improve the performance of your tires.
While I was test riding and reviewing the Foundry Harrow, Nick at BELGIANWERKX already had a plan for a custom wheel upgrade. What I thought would be an upgrade in weight turned out to be much more. A custom set of wheels allows the builder to select the exact combination of features desired from the individual components. Nick knows how to combine multiple component features to create a synergistic result, where the sum of the features is greater than the components alone. This can be a huge benefit over buying a pre-assembled wheel set where you may need to make compromises. What many may not know is that custom built wheels are typically no more expensive to buy than a comparable pre-built set. I would encourage anyone considering a wheel upgrade to consult a knowledgable and skilled wheel builder first. Fortunately for us, we have Nick Moroder from BELGIANWERKX in house.
What is “grip”?
Before we describe these custom wheels, let’s first look at what constitutes “grip” in a cyclocross tire. Most people would say that the tread pattern is the most important variable in the “grip” equation. While tread is certainly an important component of grip, it is far from the whole story. Contact area and conformity are just as critical.
Contact area refers to the amount of tire that is in contact with the ground. In cyclocross, we run lower tire pressures. Lower tire pressures allow the tire to flatten out in order to increase the amount of tread in contact with the ground. Additionally, wider tires will have more contact area than a narrow tire. Simply put, a larger “footprint” improves the grip of the tire.
Conformity, on the other hand, has to do with what is happening “within” that contact area. If the tire, tube and tread are supple, the tire will conform to every irregularity in the surface of the ground and the grip will be improved. If the tire, tube and tread are rigid, the conformity of the tire will be poor and therefore the grip will be poor, and this is regardless of the amount of contact area. In summary, a tire that has more contact area and more conformity will have more grip, and these variables are independent of the tread pattern. If these variables, contact area and conformity, are considered when lacing up a custom set of wheels, the result will be a high performing wheel that will maximize the performance of our tires.
The wide rim revolution.
Wider rims have been the all the rave in rim technology in recent years. This may seem counterintuitive, but wider rims are faster. On road bikes, the wider rim gives a more aerodynamic transition between the rim and the tire, reducing drag. Additionally, a wider rim gives the tire a more vertical sidewall and, for reasons beyond the scope of this article, reduces rolling resistance. Grip and cornering performance of a tire is also improved when the tire is moved to a wider rim. A wider rim creates a wider tire profile and therefore more contact area with the ground. When the wider rim feature is applied to a cyclocross wheel, the benefits are no less significant. Wider rim, wider tire profile, more contact area with the ground. This benefit is made even more significant because a wider tire profile allows you to run an even lower air pressure, further increasing the contact area between the tire and the ground.
Latex tubes, light and supple.
Latex tubes are a performance upgrade for two significant reasons, weight and conformity. The latex tube used on this cyclocross wheel upgrade weighs in at 207 grams. The black “butyl” tube that it replaced weighs in at 320 grams, a difference of 113 grams. This reduced the tube weight in this wheel by more than 35%. Keep in mind that this isn’t just 113 grams less weight, this is 113 grams of rotational weight. Any weight savings from around the circumference of a wheel is literally many times more significant than the same weight removed from a non-rotating component.
Just as significant is the conformity of latex. Hold a latex tube between your fingers and you will immediately feel how it is different from a butyl tube. Latex tubes are significantly thinner and more elastic than a butyl tube. “Thin and elastic” are the key characteristics of a material that has superior conformity. The thin, elastic nature of latex allows it to stretch and conform to the irregularities of a race course and then immediately rebound to its original shape. When mated with a quality cyclocross tire, this thin and elastic inner tube will improve the compliance of the tire and therefore improve the overall grip. It has been known for years that tubular tires are lighter and have more grip than standard clincher tires. It should be no surprise then that most quality tubular tires use latex tubes. By using latex tubes in a high quality, foldable clincher tire, the performance gap between tubular and clincher tires is made significantly smaller.
The custom wheel build, Nick’s creation.
The information above is nothing new to Nick Moroder. This kind of data and information is swimming around in his head most of the day. Given his in depth knowledge of wheel building and wheel performance, here is what Nick created.
The wheels Nick assembled combine a classic Shimano Deore XT hub with the latest clincher cyclocross rim featured by HED. This rim is called the HED Belgium+. The plus refers to the rim’s width, which is 25mm wide. This is compared to most cyclocross rims that are no more than 23mm wide. These wheels also feature latex tubes instead of the standard black butyl tubes.
The inside width of the rim, where the rim mates with the tire, is an even more important feature of these new rims. The HED rim has an inside width of 20.6mm vs. the typical 17mm for the stock Alex rim and others. When inflated to 30psi, the tire on the stock Alex rim measures 34.5mm wide vs. 36.5mm on the HED rim. This makes the tire on the HED rim nearly 6% wider, which improves the tire’s contact area with the ground. As mentioned above, a wider rim also allows you to run a lower air pressure than you can with a narrower rim. This lower air pressure will further increase the footprint of the tire and therefore the grip.
The tires used on the new wheel build are identical to the tires used on the stock wheels. Clement PDX 700×33 foldable clinchers are among the best clincher cyclocross tires available today. By using the same tires on both wheels, we can assume that any performance difference is a result of the wheels and not the tires.
I was fortunate enough to be able to ride these wheels in variable conditions. They were ridden hard on a dry training day and on a wet race day on back-to-back days.
My ability to lower the tire pressure was my first observation. I was able to lower the pressure from 30 psi, my normal cyclocross pressure, to as low as 25 psi without risking a pinch flat or feeling like I was riding on jello. While on the topic of pinch flats, it is important to note that latex tubes are much less likely to pinch flat than butyl tubes. This is a huge advantage for cyclocrossers who risk pinch flatting because of the low pressures required for grip.
In the dry conditions on day one I slowly started increasing my speed through every turn, looking for that limit where the grip was lost. I never found that limit in the dry weather. For the first time ever I was able to maintain speeds through the turns that I had never achieved before. This was making me faster through the turns AND saving me energy coming out. I kept hearing my new mantra, “Look ma! No brakes!”, over and over in my head as I challenged every turn to take me out. The combination of rim width and latex tubes was giving me an advantage in the turns that I had not felt before. It did take a bit of time getting comfortable entering turns at these speeds, but I never lost traction or control despite my efforts to do so.
The next day I competed in two races in Janesville, WI. The races were rainy and the course was wet but not muddy. Here was an opportunity to further test these wheels and tubes. In short, I had my best performances of the season. I found myself attacking into the turns while my competitors were slowing down. This was a freedom I had not experienced all season. I had to constantly remind myself that “it is okay to enter the turns this fast”. As my confidence built, so did my speed through the turns. Being rainy and wet, I was able to find that edge where I would start to slip. This edge, however, was at speeds I wasn’t used to doing in dry conditions on the stock wheel and inner tube package. This is a remarkable statement given that the tires used on both wheels were the exact same tires.
The question in everyone’s mind at this point is likely, “how much lighter are the custom wheels”? Weight seems to be the bottom line for many people, and this is understandable. Weight is a concrete number that makes comparisons of components quick and objective. However, as mentioned above, it is not the whole story. The truth is, I did not get a chance to weigh these wheels against the stock wheels until after the test ride and races and after writing this entire review. The result……..the new wheels weigh in at 18 grams less than the stock wheels. For many people, if they saw these wheels side-by-side on a shelf, would buy the less expensive wheels based on price. It is only 18 grams after all, right?
What is missed in this assumption is weight distribution and performance. The performance of these wheels has already been well established. What remains is weight distribution. Shimano Deore XT hubs are high quality, durable hubs. The trade off is that they are heavy. These wheels, though they weigh essentially the same as the stock wheels, have re-distributed the weight from the rim, inner tube and tire and moved it in toward the hubs. This lowers the weight around the circumference of the wheel, improving the acceleration characteristics.
In conclusion, riding and comparing bicycle equipment is a pretty subjective exercise. A so-called upgrade for one person may be unpalatable for another person. We all have different likes and dislikes. This equipment test, however, highlights a characteristic that we all want and need…GRIP. I think we can all agree that too much grip is never an issue in cyclocross. This comparison of wheel performance is significant because all variables besides wheel build and inner tube choice were kept the same. The rider, bike, tires and riding surfaces were kept constant, allowing the characteristics of the wheels and tubes to be isolated and compared. The performance improvement between the stock wheels and the custom built wheels was beyond significant. The wider rim created a wider tire footprint, and the latex tube gave that footprint greater conformity. When added together, these characteristics worked together synergistically to create superior GRIP. The weight of the upgraded wheels, though nearly identical to stock, has been re-distributed away from the circumference and toward the hubs. When I thought this wheel upgrade was going to be an upgrade in weight savings, it turned out to be a whole lot more. That is just like Nick, to once again overachieve and shatter all of my expectations.
Arlen Spicer is a Cat 3 Team Belgianwerkx member. He’s been road riding since college. This is his first year cyclocross racing. He’s already a pretty good Cat 3.