400bhp Buell Leviathan falls short of 250mph Bonneville target

Remember that 400bhp Buell that was heading to Bonneville with a 250mph target? Well, we now know how that went, and things didn’t exactly go to plan.

Project Leviathan previously set its sights on breaking the 250mph barrier, although the bike's best recorded run, that we can find, was 178.531mph.

That is obviously some way short of the headline target, but the circumstances around Leviathan’s first attempt at Bonneville aren't clear-cut, with outside influences helping to stifle the team.

For starters, neither the bike nor its rider, Jacob Stark, had ever competed at Bonneville before. The Speed Week outing was the first time Leviathan had moved under its own power outside of testing and dyno work, while Stark had never ridden on the salt. Before the team could even start chasing big numbers, they had to work through the Bonneville licensing process, which requires riders to demonstrate that they can control their machines at increasing speeds.

The first run was deliberately straightforward, as Stark needed to maintain more than 125mph to secure a ‘D’ licence, and the team kept things simple with a short-shift into second gear before returning to the pits for inspection and adjustment. That first run apparently went without drama, but things became considerably more complicated once third gear was introduced.

Buell says the character of Leviathan changed dramatically as Stark pushed the bike beyond 150mph at the two-mile mark. The team was then faced with a series of technical challenges and corrections over the following days as it worked to get the bike ready for higher speeds.

Fourth gear was the next hurdle. The problem was that selecting fourth resulted in rear-wheel speeds of more than 200mph, even though the bike itself was travelling considerably slower.

That meant Stark had to learn how to control Leviathan while effectively performing a rolling burnout at more than 175mph. It is probably fair to say that this wasn't covered in the standard motorcycle test.

Eventually, Stark secured the ‘B’ licence required to qualify for the Long Course, giving the team five miles in which to accelerate rather than the shorter two- and two-and-a-quarter-mile distances used during the earlier stages. The team then recorded its best speed of the event at 178.531mph.

That number needs to be put into context. Leviathan was built with a stated target of more than 250mph, and Buell claims the turbocharged 1190 platform produces more than 401bhp at the rear wheel, alongside more than 215lb-ft of torque. On paper, at least, there should be considerably more to come.

The problem is that Bonneville isn't a dyno, and getting 400bhp out of a motorcycle is one thing, but putting that power down on salt, while keeping the rear wheel under control at more than 200mph, is an entirely different proposition.

The team also had to deal with the reality of developing a brand-new land-speed motorcycle in competition conditions. Buell says a number of technical issues required corrections throughout the event, while Stark was simultaneously learning how to ride a machine that behaves very differently as its speed increases.

The Leviathan project originally began as a Super Cruiser prototype, with Buell CEO Bill Melvin giving Stark ‘carte blanche’ to unleash the 1190 platform. The resulting machine combines the Super Cruiser chassis with Hammerhead and 1190RS bodywork, FOX suspension, forged aluminium wheels and custom sprocket hubs designed for a claimed 300mph mechanical limit.

It was always an ambitious project, then, and Bonneville Speed Week 2026 appears to have been as much about learning what Leviathan can actually do as setting a headline-grabbing top speed.

Buell's own summary of the event is suitably understated: “The Beast has a taste for the salt.” While that may be true, it certainly hasn't had its fill yet. A 178.531mph best is a long way from the original 250mph ambition, but Leviathan has now proved that it can run on the salt, its rider has gained the necessary licences and the team has a much better idea of what needs fixing before the next attempt.

The real question now isn't whether a 400bhp Buell can do 250mph on paper. It's whether Buell can turn all that dyno horsepower into forward motion before the salt runs out.

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