wheels wheels wheels

Hey Team!

This week’s coaches corner is going to go down the rabbit hole of tech a little! Specifically wheels. I want to talk about rim depths, why you’d want a more aero wheel(and being more aero in general), tubeless, and hooked vs Straight Sidewall(hookless) wheels!

As a general rule, a deeper wheel is more aerodynamic. This is why one of the first upgrades cyclists make to their bike is a deeper carbon wheel. It’s as close as you can get to buying speed. Most riders have seemed to settle on what we like to call a mid depth. Anything from 40mm-65mm falls into this category and usually gives the best of both worlds between aero and weight. Deep enough to be more aero, but shallow enough to not add tons of weight. Generally a deeper wheel also adds weight. A deep wheel isn’t good for a mountain stage, but a deep wheel is wonderful for the descent of the mountain stage. Thus, the mid depth has taken the market. The research as of late is suggesting that weight isn’t the end all be all like we once thought. For most. weight doesn’t begin to mean more until a gradient of 7-8%. For reference, Alpe d’Huez only averages 8% meaning for the vast majority of that climb, aerodynamics is still playing a larger role on speed than weight(hint hint wear tighter kit!). A secondary downside to a deep wheel is cross winds. You will get blown around. I’m sure you’ve been on a ride and passed by a farm(think like burnt mills road) on a windy day. That gust comes and you feel like you’re being blown into traffic. A deep wheel makes this feeling worse. A lighter weight rider will also feel this effect more than a heavier one.

Okay, I’ve kept the rim depth chat short as I’m assuming most of you knew this already. If you have more questions, reach out and I’ll answer them! I want to spend more time on tubeless, why you want it/dont want it and most importantly, why straight sidewall, or hookless, has some flaws to it. This week’s email may sound more like a PSA and that’s on purpose. With the holidays behind us, I’ve had a lot of customers come in with their shiny new wheels, only to be disappointed when I explain that they can’t run certain tires, certain sizes and in a lot of cases both on their new wheels. Let’s first explain the difference. There’s two types of bicycle rims, hooked or chrochet and Hookless/Straight sidewall/TSS(tubeless straight sidewall). From here on I’ll use hooked and hookless. The difference is as it sounds. one rim sidewall has a hook that holds the tire bead, and one that doesn’t and uses the air pressure to keep the tire in place. Hookless is not a new technology. Hookless rims have been used in mountain biking for a decade. Hookless isn’t inherently dangerous. The danger has come out when it’s needed to run the higher pressures of road riding. A hookless rim has a maximum pressure of 72psi. For a rider of heavier weight, 72psi can be too low and in order to run a safe combination, they may need to ride a 38cm or bigger tire, not the ideal for competitive road riding. Just today I explained to my co-worker that his current tires aren’t approved by zipp, and the only tires we have in stock that would work are whole size up, and he can only run 50psi as that is the recommended maximum via Zipp. To boot, he doesn’t like that tire. The result of running an incompatible set up? Catastrophic failure. On a positive note, the trend of running wider tires at lower pressures is making this less of an issue, but it’s still an issue. A hooked wheel has none of these problems. Hooked systems can be optimized for the best performance for you, where a hookless system *MAY* have issues getting you the fastest set up. Personally I don’t think I’ll be on hookless anytime soon.

Tubeless! Tubeless road has hit the masses. I am a huge fan of tubeless. The ease and peace of mind is wonderful. Tubeless basically makes the traditional puncture a non issue. I’ve been explaining it to those asking as just swapping where and when you have to work on your bike. Decreasing the time spent on the side of the road fixing a flat is replaced by checking sealant and refilling in the warmth of your own home. Since swapping to tubeless, I’ve had about 3 flats in 6 years. The only thing tubeless can’t save against is a sliced sidewall. The easiest way to think about tubeless is this: if the sealant can’t plug the whole, you need a new tire. This same rule would apply even to a tubed system, if the hole is that big, you’d still have to put a boot on the tire and limp back to the car.

Like I said, this week is reading more as a PSA than a tech corner. If you’re running a hookless wheel, please make sure you’re doing so to the manufacturer’s guidelines. No one wants to crash because of an error they’ve made in setup. Please reach out to myself or Pop’s Bike Shop if you have any questions on your own wheels.


Discover more from Team Somerset

Subscribe to get the latest posts sent to your email.

Leave a Reply