Technical Q&A with Lennard Zinn | Substack

Questions About Hearts of Athletes

Heart monitoring as a diagnostic tool and coronary artery disease

2 hrs ago • Lennard Zinn

Sudden Cardiac Death of a Masters Bike Rider

Is there a test that could have alerted this very fit and seemingly healthy man and averted his death?

Feb 9 • Lennard Zinn

Tire Width Tolerances, 750D Tire Sizing, and Brake-Cleaning Solvents

How much wider or narrower is allowable? How did 750D get its name?

Feb 3 • Lennard Zinn

Tire sizing explained

What does the “C” mean? (Or the “B”?)

Jan 26 • Lennard Zinn

Making XPLR 1X work on a vintage steel road bike

Three more solutions on upgrading a Campy drivetrain for lower gearing

Jan 19 • Lennard Zinn

Most Popular

Andy Pruitt’s Final Bike Fit

Dec 2, 2025 • Lennard Zinn

Tubeless Sealant Refresh and Replacement

May 6, 2025 • Lennard Zinn

Should you ride shorter cranks?

Dec 10, 2024 • Lennard Zinn

Sudden Cardiac Death of a Masters Bike Rider

Feb 9 • Lennard Zinn

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