Ask Josh Anything #010

We've got a great batch of questions from you for Josh to contemplate this episode:

  • Does the placebo effect apply to cycling clothes and shoes as well as to equipment?
  • Since many rims are different widths in different places, where should we measure when applying the rule of 105?
  • How much — if any — does a patched tube affect a bike's CRR?
  • Are third-party ceramic bearings and oversized pulley wheels still relevant?
  • How marginal of a gain do you get with a really nice hub?
  • Is it faster to run a deeper wheel in the front than the rear?

Josh will answer all of these — and more! — in this episode of Marginal Gains (Disclaimer: the answer almost always begins with "it depends.")

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!

Subscribe using your favorite podcast platform (but be sure to rate and review us on Apple Podcasts).


  • Pari

    I have this question for a long time, but is now even more interesting after a “Placebo” episode. I ride both, MTB and Road, and for simplicity reasons use SPD pedals and shoes on both. I know for roadies this is kind of heretic, but I can live with that :) More interesting are debates that occur sometimes, about effectiveness of MTB and Road pedals (systems). And regularly, roadies claim to me that MTB system is more convenient, but Road is better in power transfer due to bigger cleat and therefore bigger contact area. And the best part is when they claim they can FEEL it! (This is definitely Placebo effect in place)

    So, is there any actual difference in power transfer between the two, if we are talking about carbon shoes soles on both shoes?

  • Marcus


    really love your podcast, glad I finally found it!

    Here is a tricky one for TT-bikes and I got quite a few opposite theories on that, depending on who you speak to in the industry: if the gear ratio is ok with that for your purpose/the course: can one skip the front derailleur to save a watt or two?


    all the way from Germany

    Marcus a.k.a. Der Baranski

  • J Vandervelde


    What is faster, a full or an empty bottle cage?

    I often see pro riders throw their water bottles away before the final kilometers of a race to lose some extra weight, but how does this influence their CdA and is the weight-loss worth it? And does this differ for a full or empty water bottle?

  • John Allison

    Hi Josh and the rest of the gang at Marginal Gainz Podcast!

    Aerodynamically speakibg, is a matte finish frame and parts faster, or slower, than a shiny, or polished frame and parts?


  • Michael Collins

    Your discussion on hubs in Ask Josh #10 made me think of this. I ride 60mm deep DT Swiss wheels most of the time with a Wahoo Speed Sensor or the rear hub. I use a Zipp disc wheel on the rear for important triathlon races when it is allowed. How much of a drag penalty is there if I move the speed sensor to the front hub? I’m I negating the benefit of the disc if I put the speed sensor on the front hub? Should I go without the speed sensor and just go off of GPS Speed? Also, how much drag different is there between the front or rear hub if I’m using the 60mm wheel in the rear for a non-disc wheel allowed race?

Leave a comment

Please note, comments must be approved before they are published

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.