Ask Josh Anything #008

We're back with more proof that we're willing to ask Josh practically anything bike-related…and that he's willing to take practically any question seriously. In Ask Josh Anything #008, we talk about what gas you should fill your tires with, the challenge of planning for endurance ride air pressure loss, marginal gains and Kipchoge's sub-2-hr marathon, which pedals are most aero and whether aero pedals matter (they do!), whether aero adjustments could make a difference in downhill MTB races (they could!) and —as always — much more.

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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  • Nick

    “Back in the day” we used to use liquid latex to fill the gap between tubular tyres and the rim (which then set) is there anything in that? Did it cost more Crr than the aero gain? Also on the topic of aero tyres, there was a period with quite a few – zipp tangente, bontrager aerowing and R4 aero. Any thoughts on why they went away, will aero tyres come around again?

  • Nels Hackl

    Question for the next appropriate podcast: Rim Width

    I have a new gravel frameset on order that can accommodate a wide range of tire widths. The next part of the project is to build a wheel set for 25-28 mm road tires and a second set for 35-40 mm grave tires. I am currently baffled by the current choices in rim width. For road, I can purchase rims with an internal width anywhere from 18 to 21 mm. For the gravel rims, I am looking at rim widths from 21-24 mm. Any thoughts on which rim widths would optimal for me? Thanks for your consideration.

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