In the May 1974 issue of Dirt Bike, an interesting motorcycle was featured – the prototype Aquavarna amphibious dirt bike. Although no other references to this bike have been found, here is the story of the 1974 Aquavarna 450 as written by staffer George Wegner.

Someone in Ann Arbor, Michigan, has developed a groundbreaking waterproofing technique. This dedicated individual, Peter “Gills” Dill, has combined his love for dirt biking and scuba diving to create an innovative amphibious motorcycle. His invention, the Aquavarna 450, caught the attention of Dirt Bike magazine, and they decided to put it to the test as the “MASTER TESTERS”.

The test session took place at Lake Michigan, where the Aquavarna amazed the testers. Equipped with a scuba regulator connected to the rider and a modified Husky air box, the bike could be ridden completely submerged. The waterproofing technique used by Dill remains a secret, but it is suspected to involve Elmer’s Glue, malted milk balls, and WD-40.

During the test, the bike achieved a top speed of 14 knots underwater, offering a unique and exhilarating riding experience. The traction was impressive, allowing the rider to maneuver through underwater obstacles effortlessly. Even crashes were enjoyable, as the rider would simply settle to the bottom.

After the successful test, the Dirt Bike team discussed potential improvements for the Aquavarna, including adding fins or rudders for better cornering stability. Gills, the inventor, was invited to join the team as a “Special Underwater Consultant and Test Editor”. The article concludes with a mention of a future cycle park opening off the coast of Delaware, where enthusiasts can explore underwater biking.