# This Bike Was A Total Joke. Then It Broke Records Source: https://www.youtube.com/watch?v=f3vp4scTMSo Recap page: https://rapidrecap.app/video/f3vp4scTMSo Generated: 2025-07-27T12:32:26.958+00:00 --- ## Quick Overview The Pinkbike "Grim Donut" bike, initially a joke with a wildly slack geometry, surprisingly performs exceptionally well downhill, though it struggles with climbing, proving that sometimes unconventional designs can lead to impressive results. **Key Points:** - The "Grim Donut" bike, with its extreme 83-degree head tube angle, performs surprisingly well downhill but is almost unrideable uphill. - The bike's slack geometry, while making climbs and flat terrain handling difficult, excels on descents, allowing for high speeds and stability. - Pinkbike's testing revealed that the Grim Donut's unique geometry allows it to handle rough terrain and turns exceptionally well downhill. - The bike features a custom linkage and a 135mm/160mm suspension travel setup, with the front travel being longer than the rear. - The "Grim Donut" branding and custom graphics, including a bat-like creature on the hubs, add to its unique and humorous appeal. - Despite its challenging climbing characteristics, the bike's overall downhill performance was praised by testers. - The experiment highlights how radical geometry changes can lead to unexpected performance benefits in specific riding conditions. ![Screenshot at 00:01: The presenter, Mike Levy, introduces the "Grim Donut" bike, showcasing its extreme and unconventional geometry that makes it look like a joke.](https://ss.rapidrecap.app/screens/f3vp4scTMSo/00-00-01.png) **Context:** This video from Pinkbike features Mike Levy and his colleagues as they test a mountain bike called the "Grim Donut," which was initially conceived as an extreme, joke-like design with a very slack geometry. The video explores the evolution of mountain bike geometry, particularly the trend towards slacker head tube angles, and how this affects a bike's performance. ## Detailed Analysis This video explores the "Grim Donut," a mountain bike born from a joke that ended up being a surprisingly capable downhill machine despite its extreme geometry. Initially conceived with an 83-degree head tube angle and a very slack design, the bike's creator, Mike Levy, and his colleagues at Pinkbike set out to test its limits. They discovered that while the bike's steep head tube angle makes climbing almost impossible and handling on flatter terrain awkward, its slack geometry excels on descents. The bike's design, which evolved from a 2010s trend of slacker head tube angles, proved to be a testament to how geometry impacts performance. The video details the bike's build, including its custom linkage and components, and showcases its exceptional downhill capability on challenging terrain. Despite its oddity, the Grim Donut's ability to maintain speed and composure on descents, even with its challenging climbing characteristics, makes it a noteworthy and successful experiment in bike geometry. ### Bike Concept - The "Grim Donut" was created as a joke with extreme geometry, featuring a very slack head tube angle. ### Downhill Performance - The bike excels on descents due to its slack geometry, maintaining speed and composure. ### Climbing and Flat Terrain Handling - The bike struggles significantly on climbs and flat terrain, making it almost unrideable. ### Geometry Evolution - The design reflects a trend towards slacker head tube angles in mountain biking over the past decade. ### Design Details - Features a custom linkage, 180mm front travel, 160mm rear travel, and unique branding like the "Grim Donut" logo and a bat-like creature on the hubs. ### Testimonials - Riders found the bike terrifying on climbs but surprisingly capable and fun on descents, despite its handling quirks. ![Screenshot at 00:01: The presenter introduces the "Grim Donut" bike, highlighting its unusual geometry.](https://ss.rapidrecap.app/screens/f3vp4scTMSo/00-00-01.png) ![Screenshot at 00:12: A close-up shot of the bike's front wheel and fork, showcasing the pink spokes and "Fox" branding.](https://ss.rapidrecap.app/screens/f3vp4scTMSo/00-00-12.png) ![Screenshot at 00:22: A title card displays "RACE RUN GRIM DONUT" with a first-person view of the bike on a trail.](https://ss.rapidrecap.app/screens/f3vp4scTMSo/00-00-22.png) ![Screenshot at 00:45: The video shows the "Grim Donut" time of 2:03:92 with the presenter and another rider giving a high-five.](https://ss.rapidrecap.app/screens/f3vp4scTMSo/00-00-45.png) ![Screenshot at 01:05: A scenic overview shot of the mountainous landscape where the bike was tested.](https://ss.rapidrecap.app/screens/f3vp4scTMSo/00-01-05.png) ![Screenshot at 01:25: A close-up of the bike's front fork, highlighting the "Fox" branding and "ZEE" lettering.](https://ss.rapidrecap.app/screens/f3vp4scTMSo/00-01-25.png) ![Screenshot at 01:38: A graphic overlay shows the head tube angle of a similar bike at 65.5 degrees.](https://ss.rapidrecap.app/screens/f3vp4scTMSo/00-01-38.png) ![Screenshot at 01:53: Another graphic overlay shows the head tube angle of the Grim Donut at 58 degrees.](https://ss.rapidrecap.app/screens/f3vp4scTMSo/00-01-53.png) ![Screenshot at 02:24: A first-person view of the bike navigating a rocky section of the trail.](https://ss.rapidrecap.app/screens/f3vp4scTMSo/00-02-24.png) ![Screenshot at 03:45: A diagram showing the bike's geometry with various measurements and angles.](https://ss.rapidrecap.app/screens/f3vp4scTMSo/00-03-45.png)