Velo Podcast

Featuring: Mike Levy, John Karrasch, and Jan Heine

Does a 32-inch wheel actually save watts, or is the testing methodology broken? We put Chung Method advocate John Karrasch and vocal critic Jan Heine in the same room to hash out the reality of rolling resistance.

This week, the usual crew steps aside to host a direct debate between two of the most outspoken voices in tire tech. John Karrasch (aka flexfitbyjohn) has generated massive datasets using the Chung Method, recently claiming that adopting 32-inch wheels can improve rolling resistance by up to 10%. On the other side, Rene Herse CEO Jan Heine—a pioneer of supple gravel tires—argues that wheel size ultimately doesn't matter for speed, pointing to historical roll-down tests and potential flaws in the Chung Method's precision.

After a long series of online blog posts and rebuttals, we brought them together to debate the physics, the testing protocols, and the future of gravel geometry face-to-face.

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Episode Timestamps

00:00:00 - Episode Intro & Guest Backgrounds

00:07:51 - Setting Up the 32-Inch Test Bikes

00:12:12 - Understanding the Chung Method for Tire Testing

00:16:18 - The Results: Do 32-Inch Wheels Roll Faster?

00:25:01 - Analyzing the Physics and Approach Angles

00:29:32 - Jan Heine's Counterargument: Wheel Size Doesn't Matter

00:36:58 - The Debate: Is the Chung Method Too Precise?

00:42:36 - Defending the Data and Real-World Variables

01:03:15 - Tire Design Priorities: Casing, Compound, and Pressure

01:17:11 - Tire Inserts and 36-Inch Wheel Possibilities

01:18:57 - 2030 Gravel Bike Predictions & Outro

Featuring: Mike Levy, Josh Ross, Lisa Charlebois, and Logan Jones-Wilkins

This week is easily one of our favorite recent episodes. All four Velo podcast hosts—Lisa Charlebois, Logan Jones-Wilkins, Mike Levy, and myself—are together in the virtual studio, and things get incredibly spicy. Expect a lot of passion and plenty of heated back-and-forth as we debate drivetrain futures, prototype spy shots, and the true definition of bikepacking.

We kick things off with listener questions. What starts as straightforward bike-buying advice quickly devolves into an argument over whether bikepacking is strictly a gravel activity and if camping is actually required. Josh also gets a chance to double down on why there is more to a bike than its spec sheet, specifically making the case for the Cannondale CAAD14.

Next, the conversation shifts to the newly spotted 13-speed Shimano Dura-Ace prototype. Because the system still relies on wires, the analysis quickly spirals into a broader SRAM vs. Campagnolo vs. Shimano showdown. The crew splits on what matters more: Shimano’s shifting precision or the glaring gaps in the rest of the brand's ecosystem.

Finally, the main event. Following a week of dueling op-eds, Logan and Josh bring the drivetrain battle to the microphone. Is 1x the inevitable future of road bikes, or will the slow-to-change road market ensure 2x remains superior? Listen to the arguments, read the articles on the site, and vote in the Velo poll to settle the score.

00:00:00 - Intro

00:02:52 - Listener questions: Bikepacking definitions and the Cannondale CAAD14

00:25:45 - Shimano 2x13 prototype and the great drivetrain brand war

00:53:41 - 1x vs. 2x on the road

Read More on Velo

Front Derailleurs Are Living on Borrowed Time: Why 1x on the Road Is the Inevitable Future

Opinion: You Can Take My Front Derailleur When I am Dead

The Velo Drivetrain Poll: Is 1x or 2x the Future of Road?

Featuring: Mike Levy, Josh Ross, Lisa Charlebois, and Logan Jones-Wilkins

The Vuelta a España is in full swing, and this week the whole crew is in the house to break down the racing, new tech, and the latest industry chaos. Host Mike Levy is joined by Logan Jones-Wilkins, Lisa Charlebois, and Josh Ross to cover:

Vuelta a España Wackiness: The race has a reputation for the unexpected, and Logan and Lisa walk us through the organizers' questionable decision to hire a specific influencer. It seems nobody vetted the content before handing over the credentials, and the resulting shock was entirely predictable.

New Silca Tires: Logan gives the rundown on Silca's latest rubber and the inevitable claims of being the absolute best. Josh jumps in with intel directly from Josh Poertner, who he caught up with at the MADE show, to explain why the master of marginal gains chose to make a road tire that explicitly isn't aero-optimized.

The Best of the MADE Show: Josh spent the week shooting rolling art and picked his five favorites. We dive into his absolute top choice. No spoilers, but it features exposed cables, is built for ultra-endurance distances, and comes from fellow Oregon resident Rob English, who builds highly functional steel frames just down the road.

Van Rysel Gravel Reviews: Lisa drops two reviews covering the newly launched Van Rysel gravel line. We look at the adventure model that somehow maxes out with only a 50mm tire, and the crew gets into the weeds on why the "racy" version should probably be categorized as an all-road bike rather than a dedicated gravel racer.

Timestamps:

00:00 - Intro

02:47 - Pogacito

14:32 - Silca tires

33:45 - MADE bike show

44:22 - Van Rysel EDR-G and RCR-G review

Featuring: Mike Levy, Josh Ross, and Lisa Charlebois

We air out our worst group ride habits, explain why the CAAD14's aluminum vibe beats cheap carbon, and tackle reader questions.

In this episode:

Toxic Cycling Traits: What's the thing you do on the bike that the group ride probably hates? Levy admits to half-wheeling, I talk too much, and Lisa... well, you'll have to let us know if her trait is actually a big deal.

The Cannondale CAAD14: I’ve had this bike all summer and absolutely love it. We discuss how a mistake by Cannondale made the bike better, why it's an incredible value, and why other reviewers are entirely missing the point. It doesn’t matter that there are cheaper, faster carbon bikes out there; the CAAD14 has an undeniable vibe.

Reader Q&A: With Logan Jones-Wilkins off at Leadville playing at high altitude, Lisa, Levy, and I take over the mic to answer your questions. Would Logan have suggested a Trek endurance bike instead of the gravel bike I recommended? We also touch on the massive new 32-inch Mosaic that launched this week.

We want to hear from you:

What is your toxic cycling trait? Also, have you ridden a CAAD bike and know exactly what I'm talking about, or am I off my rocker and people should just buy cheap carbon instead? Let us know!

Articles covered in this episode:

Review: Cannondale Made a Mistake and the CAAD14 Is Better for It

The New Trek Domane is Too Good to Call an Endurance Bike

The New Mosaic 32 Gravel Bike Fixes 32-Inch Gravel Bikes' Biggest Problem

Featuring: Mike Levy, Josh Ross, Lisa Charlebois, and Logan Jones-Wilkins

The Velo tech team breaks down a week of massive summer rides, including fueling disasters on a 1x Factor One and why Trek’s endurance labeling might be entirely wrong.

It is the height of summer, and right now, we are doing some massive rides. We are all here this week—including Lisa Charlebois, Logan Jones-Wilkins, Mike Levy, and Josh Ross. This week we talk about how Logan just did a century on a new bike, but before we get to that, it was Josh's turn to discuss a “big dumb ride.”

The 220-Mile Aero Experiment: Last weekend, Josh took the Factor One to the beach and back from Portland. It’s a 220-mile ride with 14,000 feet of elevation, and the base build of the One wasn’t extreme enough. To set things right in the aero world, he swapped the wheels for a staggered Zipp 858 NSW / 454 NSW setup and paired that with a SRAM 1x XPLR groupset. We start by talking about how that 13-hour ride went, including the fueling mistakes that led to violently retching on the side of the road.

Seven Centuries in Seven Days: Last week, Lisa declared she’d be doing a century a day for seven days. She crushed it and recorded the numbers. She rode for 52 hours, but how many pounds of sugar did she consume during that time? We discuss the fueling, and Levy reveals why the number of people she rode with is actually the most surprising part of the whole thing.

Testing the Trek Domane 5: We bring home the discussion with Logan and the century that was just a small part of the 650 miles he spent on the Trek Domane 5. Trek calls it an endurance bike, but is that what it actually is? It weighs only 14 lbs and will take up to a 40mm tire. Is there a better name for it? Logan walks us through his thoughts on the bike, including why he loves it so much.

Timestamps:

00:00 - Intro

00:35 - 220 mile ride on a 1x aero race bike

18:52 - A century a week results and figures

28:27 - Trek Madone review

Articles covered in this episode:

The New Trek Domane is Too Good to Call an Endurance Bike