About kellersprinter.de

From painful indoor training to an authentic ride feel.

The story of kellersprinter.de is really the search for the perfect ride. Anyone who now sits pain-free on a smart trainer for hours has probably forgotten how uncomfortable the early days of direct-drive training could be. Here’s the short version of how a back problem turned into an open-source project.

The Evolution of the Rocker Plate

2017: The Smoking Trainer and a Rigid New Start

After I literally smoked my old BKool wheel-on trainer, it was time for an upgrade: my first direct-drive smart trainer, the Wahoo Kickr v3. Disappointment followed immediately. With the rear wheel removed and the frame clamped rigid, all natural flex was gone. The first rides were agony for my whole body. The expensive newcomer was close to being thrown out.

The Battle for Comfort: From Foam to Mechanics

To dampen the rigid setup, I started stacking foam mats under the Kickr’s feet. That helped for rides over an hour, but the higher the stack, the more vague and uncontrollable the ride feel became.

The Community Breakthrough

In US Facebook forums I found like-minded people. Through intense exchange, a new basic concept emerged: trainer and bike go on a solid board, with a mechanism underneath for left-right rotation. Optimising the damping became an obsession — from various foams to tennis balls to air cushions, until inflatable balls turned out to be the ultimate setup. The SprintBoard was born.

The Escalation: Showroom & Experience Centre

The tinkering project for friends quickly became something bigger. When well-known YouTubers tested the SprintBoard, interest exploded. The hobby grew into a real venture: a showroom and experience centre for eCycling and eRacing came to life. Almost every major smart trainer brand on the market was available for testing — and I also sold trainers and complete indoor cycling accessories directly.

The SprintBoard itself made waves well beyond the hobby scene. Whether in the compact S or the large XL version, demand was enormous. From eCycling beginners to road pros still racing on the UCI World Tour today, everyone trained on our boards. In the community the name became a generic term: just as “Hoover” means vacuum cleaner, “SprintBoard” became a synonym for the rocker plate itself. This network, and feedback from thousands of training hours, allowed us to perfect every last detail of the setup.

2022: The End of Hardware Sales

The commercial chapter is firmly in the past. The sale of smart trainers, indoor accessories, DIY kits and finished SprintBoards has been discontinued entirely. Kellersprinter is today exactly what it was at the very beginning: a purely recreational hobby with no financial agenda whatsoever.

Today: Free Knowledge for the Community

The passion for eCycling has remained, and the knowledge accumulated during the showroom years I share here with the community — completely free and ad-free.

Grab the build guide, head to the hardware store, and bring the authentic outdoor ride feel straight to your indoor trainer. And when your setup is done: I always love seeing a photo for the Community Builds gallery!

Ride On,
Rüdiger

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