This is a recently restored Jak Pak 300, it’s a highly unusual off-road motorcycle featuring double inline rear wheels that are both powered, offering substantially improved hillclimbing ability.
There were three primary Jak Pak models made, all closely related. They were the Jak Pak 100, Jak Pak 200, and Jak Pak 300, with the price and feature list increasing as the model numbers climbed. Interestingly, the Jak Pak 300 was said to be street legal with the addition of a speedometer, rear view mirror, and a horn.
As you can see here both the rear wheels are powered by a linked chain and sprocket system. This has the added benefit of driving both wheels at the same speed regardless of traction.
The Origins Of The Jak Pak
The Jak Pak, alternatively written “Jak-Pak” by some, was built by the Right Way Manufacturing Corporation of Owen, Wisconsin for a handful of years, with production ceasing in 1971 after an estimated 125 vehicles had been built. Owen is a tiny rural town with a current population of just 940 that sits closer to Minneapolis than its own state’s largest city of Milwaukee.
How the company came to be founded there is lost to history, and relatively few examples of the unusual “inline tricycle” that they manufactured are known to have survived. The engineer and inventor behind the design was Richard Gostomski, originally of Thorp, Wisconsin which is just a few miles east of Owen down the World War I Veterans Memorial Highway 73.
Gostomski’s design was quite clever, running the two wheels in tandem at the back and providing them both with power give the simple motorcycles excellent hillclimbing ability, and it increased their cargo capability.
The Jak Pak: Specifications
The Jak Pak features a tubular steel frame with a centrally-mounted Tecumseh 7 bhp flathead single-cylinder gasoline engine that drives the rear wheels through an automatic torque converter. It relies on its beefy tire sidewalls to provide limited front suspension, but in the rear you’ll find an unusual two-piece box-section tubular steel swing arm with dual rear shock absorbers.
The bike comes with two rear seats, but the aft seat can be removed when you need to carry cargo, bags, additional fuel etc. The front tire is 16″ x 6.5″ x 8″ and it has two large 18″ x 9.50′ x 8″ rear tires which are both powered by two chains linked by sprockets.
Then Jak Pak 300 has a dual 12 volt alternator, a daul beam headlight, a brake and tail light, and a horn. The top speed is said to be 35 mph though there’s no word on what a realistic cruising speed would be. Regardless, this is a vehicle really designed for off-road use.
As an inline-tricycle the Jak Pak 300 shows what ultimately would be an evolutionary dead end. The more traditional tricycle layout with the single front wheel and twin rear wheels fitted in parallel would quickly become the dominant form factor, initially on vehicles like the Honda US90 used in James Bond’s Diamonds Are Forever and the later Honda ATC70 that would become a favorite of the Jackson 5.
Power is provided by a centrally-mounted Tecumseh 7 bhp flathead single-cylinder gasoline engine that drives the rear wheels through an automatic torque converter.
By the mid-1980s it would become clear that this type of three-wheeler was simply too dangerous for the general public due to the risk of tipping over, in this way the Gostomski-designed Jak Pak was far superior, and eventually quad bikes would take over altogether.
The Jak Pak 300 you see here is a recently restored example, and it’s now the single nicest example of the rare American-made three-wheeler that we’ve yet seen come up for sale. It’s being offered at no reserve in Florida for off-road use only with a bill of sale and you can visit the listing here if you’d like to read more about it or register to bid.
Images courtesy of Bring a Trailer
Articles that Ben has written have been covered on CNN, Popular Mechanics, Smithsonian Magazine, Road & Track Magazine, the official Pinterest blog, the official eBay Motors blog, BuzzFeed, Autoweek Magazine, Wired Magazine, Autoblog, Gear Patrol, Jalopnik, The Verge, and many more.
Silodrome was founded by Ben back in 2010, in the years since the site has grown to become a world leader in the alternative and vintage motoring sector, with well over a million monthly readers from around the world and many hundreds of thousands of followers on social media.
