Ask Josh Anything #19

Drivetrains, aero tweaks, and wheels have emerged as the sweet spot for where listeners can achieve marginal gains on their current bike setups, and this episode will really scratch that itch. We do a deep dive into the why, how, and what of Silca's new diamond-polished chains, how properly-lubed chains affect cog and chainring wear and tear, and whether you really need to replace that quick link after each chain connect/disconnect cycle. We also get to the best ways to locate your hydration on long rides and the question of whether — wheelwise — deeper is always better.

Got a question you’d like to ask? Text or leave a voicemail at the Marginal Gains Hotline: +1-317-343-4506 or just leave a comment in this post!

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  • Sam Guerra

    Hi there! My name is Sam Guerra from Orange County, California.

    Question for you regarding wheel depth. I have a set of 42mm and a set of 60mm, both carbon, wheel-sets. Both weigh virtually the same but the 42mm are much more stiff and snappy.

    I race crits and longer events like centuries+. My normal set up is to ride the 60mm for crit races and flat centuries/training rides. I use the 42mm for most training days and longer events with more elevation gain.

    Without getting into the nitty gritty of the details in the wheel-sets, theoretically how much climbing would an event need to have to make the 42s a better choice than the 60s?

    I am a light rider at 140ish lbs and bike weighs 16 lbs so I do get tossed around by the wind a little bit when riding the 60mm.

  • Ron S.

    I have a question that may be silly but here it goes. I have participated in a few slowtwitch aero and VE discussions and I was wondering if you can get rid of most of the variables could you actually accurately calculate the power(and I mean accuracy not precision). Here is what I was thinking, you build a bike with a faring that’s would resolve the issue of CdA variability, the other variables you can accurately measure such as weight, temperature, humidity, speed, or neutralize by making them constant for the test such as Crr. The course is set for zero net elevation gain a la Robert Chung. Then you need an accurate anemometer/ pitot tube to determine air speed and yaw. You make the test platform bike so that you can fit various power meters and compare the power from the meter to the calculation. Can this work? Could this be able to test various power meters for accuracy? It seems like I am missing something so that is the question, why would or wouldn’t this work.

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