In honor of "Back to the Future" turning 40, industry experts like Ryan Fortnine, Matt Oxley, and Ari Henning take a trip back in time with Zack & Spurg to explore five massive motorcycle "What if" scenarios:

What if Boeing built motorcycles?

What if Harley-Davidson abandoned "heritage" for "cutting-edge"?

How would a different World War II outcome have changed German and Japanese engineering?

What does a truly safe motorcycle look like?

If gas motorcycles were banned tomorrow, would the community survive on electric and hydrogen alone?

Plus, Zack analyzes his actual Alpinestars airbag crash data, comparing his 65-mph highside to Marc Marquez's infamous tumbles.

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Is Marc Márquez the greatest of all time? To kick off the 2026 MotoGP season, Zack and Spurg sit down with legendary racing journalist and historian Mat Oxley to discuss why Márquez is a "generational talent".

They dive into the incredible story of how Marc learned to save front-end slides with his elbows, the countless surgeries it took to keep him on the grid, and how Spain has created the most successful racing culture in the world.

The guys also take a look towards the future at the 2027 MotoGP rule changes that could reset the entire field—and whether Márquez's body will let him stick around to see them.

This entire conversation was inspired by Mat's new book, "Marc the Magnificent: Seven-times MotoGP King". To check out Mat's book for yourself, here is a link to his website.

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The $6,000 Harley-Davidson, Honda's automatic clutch, the "vicious" KTM 990 RC R superbike, and much, much more are discussed as Zack and Spurg preview the most exciting motorcycles, tech, and industry shifts coming in 2026!

We also have an "Am I the A-hole" debate involving a delivery robot and a parked Harley… and we're joined by gear expert Pat McHugh to discuss the future of hearing protection: Cardo's active noise-canceling helmet.

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Can you imagine crashing a superbike at a press event in a foreign country? Zack can! Zack Courts returns to the show and shares his experience (both on and off the track) at the KTM 990 RC R press event in southern Spain.

Spurg & Zack also discuss changes in motorcycle policy at the Circuit of the Americas and whether or not a high BMW price tag is worth it off-road.

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In the last episode before Zack's triumphant return, Spurg and guest host Ari Henning celebrate the 40th anniversary of the Suzuki GSX-R by digging into its rise, fall, and rebirth as one of the most prolific motorcycles in the industry.

The guys also dive into the challenge of finding a good used GSX-R and discuss the "Gixxer Bro" culture. Plus, stick around for a very special Engine Sound Guessing Game!

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The legendary Ryan from FortNine drops in to go deep into his most ambitious project yet: a feature-length documentary chronicling a record-breaking, 16-day motorcycle trip around the entire world.

With Zack Courts still out on the mend, Spurgeon Dunbar is joined by CTXP producer Spenser Robert to ask Ryan about his chaotic time in India, the freezing "Nullarbor" of Australia, the logistical miracles worked by Ducati fixers at the Turkish border, and what it's really like to live on a bike for 24+ hours at a time.

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Spurgeon is joined by Common Tread's Lance Oliver to take a deep dive into the financial and structural changes rocking the Harley-Davidson corporate world. From a surprise CEO change (Artie Starrs from Topgolf and Pizza Hut) to a dealer revolt and the future of the brand, we're cutting through the clickbait to deliver a rational, fact-based look at the Motor Company.

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The Motorcycle Dating Game returns! Patrick Garvin and Spurg match Highside/Lowside listeners to their perfect motorcycle. And they all lived happily ever after!

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Fan-favorite Lance Oliver joins HSLS to break down the biggest news from EICMA 2025: The surprising new Suzuki SV-7GX, BMW's controversial F 450 GS (and its AI photos), Honda's wild V3R 900 E-Compressor concept, and the rise of brands like CFMOTO and Royal Enfield. Plus, they debate the "trickle-down" tech trend and ask: are big motorcycle shows like EICMA even relevant anymore?

But where is Zack Courts? Spurgeon Dunbar explains Zack's absence (get well soon!) as well as the engine-sound guessing game, whether or not you should get a bigger bike, and much more!

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It's the Highside/Lowside Season 10 finale, and we're going out with a bang! World Superbike racer Garrett Gerloff joins Zack and Spurg for a wide-ranging conversation that covers everything from the mindset of a pro racer to the simple joy of riding a Yamaha Zuma.

If you've ever wondered what a world-class rider thinks about group rides, speeding tickets, or even the Honda Gold Wing, this is the episode for you.

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