rxspeed presents

Race to 300

Achieving 300 mph in a standing mile has never been accomplished on a motorcycle, but a few men from Connecticut are building the world’s first compound-turbo Hayabusa to make it happen.

Hass-Serafini Racing Turbo Hayabusa

Racing is dangerous. Lives are lost. On top of highly-advanced machines, inches separate the asphalt below and the human flesh above. At speeds of up to 300 mph, one mistake and the ground is deadly.

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Steve Serifini, owner of Fab-U-This in Torrington, Connecticut, has been fabricating custom headers, exhaust and award-winning builds with some of the most intricate and beautiful weld work in the industry for the past 25 years, 15 of which at Fab-U-This. The two have worked together through their love of motorcycles, originally working on Hass’s GSXR 1000. “He [Steve] does the fab work on my 1000cc and I decided to build something different and no one has seen before,” Hass confirms. “I want to make more power. The original plan was to do it as a 1000.”


Hass continues, “I started buying parts and the turbos; I had a 1000 chassis. Everything started going together. I started thinking about the engine cases cause at the time I was doing this, I started making big boost and having problems with the 1000 engine cases. And if I’m having problems with this turbo, [our new] setup is going to blow it apart.”


The new setup—based around a 2004 Suzuki Hayabusa chassis with the neck raked five degrees—is a solution taken from Hass’s experience as a heavy equipment and diesel mechanic, where one night browsing on the internet he stumbled on a compound turbo setup from one of the diesel forums. Serafini remembers the exchange, “Don sent me a picture of a compound turbo setup, because it’s big on the diesels and you can run a ton of boost with very little lag; it comes on quick.” The consensus was decided that it would be a “fun thing to try” so after tossing the concept around, Hass left building the world’s first compound turbo motorcycle—and potentially the first to 300 mph in one mile—to Serafini.


“It was one of those things that if we counted the man hours, it would probably disgust me."


“I told Steve, this is the concept I want, I think we should put the turbos here and I’m leaving the build up to you,” Hass says. “Build it as you want to build it.”


Compound turbos are a great solution because of the power delivery and high boost numbers. In this case, Hass-Serafini is projecting around 60-70 psi on an alcohol setup. In order to compensate for the temps and extra boost, Serafini built a custom 5-gallon ice tank to hold (you guessed it) ice water that circulates through the liquid-cooled intercooler. Even during hot and humid days on the dyno, they were seeing frigid temps and impressive numbers: 564 horsepower @18psi.

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Compound Turbo

As I look over the bike, which in person makes you appreciate the time, money (lots of it) and effort this took to build, Serafini explains the benefits. “You could run it with gasoline, but the alcohol is such a cooler burn [Ed. Note: They are seeing 38-42 degrees in the intercooler]. With all that boost you’re going to make, all that extra heat, with the alcohol you can drop the temperature down and you make more horsepower with the alcohol anyway. Originally we weren’t going to run an intercooler, but Shane Tecklenburg the tuner recommended we have an intercooler. A lot of other riders use methanol spray to knock the temp down and helps with detonation. It takes twice as much fuel to run on alcohol.”


Dangerous conquests require the vision—not only the idea—to be successful and ultimately safe in the long run. Countless hours, many of which were spent by Serafini just staring at the naked Hayabusa chassis, ticked away while he contemplated the best and smartest way to put it all together. “It was one of those things that if we counted them [man hours], it would probably disgust me,” Serafini laughs. “Everything had to be four steps ahead because it was gonna screw you if you didn’t.”


Hiring some of the best names in the business and buying the best parts to further add to the cache of what they’ve dreamed, Hass-Serafini chose Steve Knecum of Knecum Performance Engines to build the beast and Shane Tecklenburg to tune it; bringing it all together. The result is a bulletproof motor running custom everything, from pistons and camshafts to the compound turbo system that has a low and a high-pressure triple-ball-bearing unit from Comp Turbo.

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How the compound turbo works: the low-pressure turbo draws air from the atmosphere; the pressurized output is plumbed into the high-pressure turbo inlet. The output of the high-pressure turbo runs through the intercooler into the plenum. This process "compounds" the boost effect increasing efficiency, and dropping turbo lag by a large degree. And by all accounts, it seems to be the first time anyone has ever effectively run it on a motorcycle. And while lag still exists, the range of rpm where a single, large turbo would be laggy is reduced because the smaller turbo can spool with less airflow—much like a sequential turbo setup.


“I could go two years and not see a good day to race.”


“People are like “how did you figure this out?”” Hass says. “And that’s Steve staring at the thing for hours and hours and hours.” Their first pass was with a single wastegate, which made so much exhaust it couldn’t get out the wastegate fast enough. That day, on the last pass, it made 42psi when it was supposed to make six. “I went 223 [mph] with the fairings blowing a tire off at 42psi and that had a tailwind.”


Weather’s a huge factor for land-speed record attempts, and one that cannot be controlled. Crosswinds are the killers of any type of record attempt, especially for motorcycles where a rider can veer hundreds of feet from side to side. When the bike is naked, crosswinds don’t affect the bike as much, however, with the Air Tech fiberglass body panels, any sort of wind moves the bike around violently. “For the time and money spent and to only have 10 passes on it: the handling, brakes, power were fine and everything is doing what it’s supposed to do,” Serafini says with enthusiasm. “We went to the wind tunnel to get a handle on aerodynamics and make sure were spot on. Basically next year, it’s up to mother nature and we should be able to go after the goal we’re trying to get.”

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Get A Grip

“I could go two years and not see a good day to race,” Hass admits. “You gotta know when to say “it’s not a good day to go out”. With the smallest crosswind you can’t run it.” Hass may get frustrated at the lack of available seat time, especially in the turbulent conditions of the Northeast, but you can sense in his voice that it’s just the nature of racing. When the time comes, he’ll be ready.


Hass is a competent and skilled mechanic in his own right. Serafini, the skilled fabricator, applauded Hass’s efforts in the wiring. “Don probably has over 100 hours in just wiring,” Serafini acknowledges. “I look at the stuff I did and I want no part in the wiring. “I’m meticulous when I do work, so I separated everything and tagged it,” Hass responds. “It makes it easier so you don’t have to hunt for every wire. It’s the best harness I’ve ever built.”


"If it saves a life by telling them two different things, then we just saved a life.”


The team works incredibly well together as each has their own set of skills, whether its Serafini’s fab work or Hass’s piloting of this jet they call a motorcycle. This pursuit—and mostly all racing—has secrets that are closely guarded from prying eyes, but Hass-Serafini admit to sharing data that might be beneficial to the entirety of the sport.


“We kept it a secret for all that time [three years] because we didn’t want people to copy the ideas,” Serafini admits. He continues, “I built a lot stuff for different people and some of it got knocked off before so I kept this behind closed doors. However, we helped others with what we’ve learned in the wind tunnel. If it’s going to help with [preventing competitors] from crashing we’re going to share what we’ve learned. It’s one of those things where if [they] go faster than us with the same body then we didn’t do our homework and kudos to them. If it saves a life by telling them two different things [to change], then we just saved a life.”

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"I can’t believe we’re building a bike that goes 300 mph. That’s not a normal conversation that you have with somebody.”


There are martyrs and heros in this dangerous sport. Renowned land speed record holder, Bill Warner, was killed pushing the limits going for the same record as Hass-Serafini. He was four mph short of the goal, and both Hass and Serafini acknowledge his influence and dedication to progressing the sport, ultimately becoming the spark and inspiration for building the bike to what you see today.


“He’s [Warner] the main reason the bike got built in the first place,” Hass admits. “I painted my 1000 his colors to honor him.” Serafini recalls the chase to keep up with Warner and the conversations he had with Hass. “If someone’s gonna go 300, then you gotta challenge it so let’s challenge Bill as a good thing and let’s try to do this. I can’t believe we’re building a bike that goes 300 mph. That’s not a normal conversation that you have with somebody.” PQ


Over the winter, the team will be changing around the exhaust a bit to go behind Hass’s feet, and hopefully obtain a sponsorship for their pursuit to help with costs, as most of the money has been self-funded by Hass himself. The general consensus is on their side, too. Many in the small community agree that this is the future of the land speed record, and what they're building is revolutionary.


You can really sense the stress, excitement, passion, long days and nights in both their voices. In a sport where Mother Nature plays an equal role alongside skills, money and expertise at deciding how well they’ll do and how fast they can go, the team of Hass-Serafini only has a matter of time before this amazing build breaks the 300-mph barrier.


Hass-Serafini Motorcycle Specs


Builder: Steve Serafini of Fab-U-This

Rider: Don Hass




2004 Suzuki Hayabusa


Raked 5-degrees by Fab-U-This

Trac Dynamics swingarm under braced by fab-u-this

Custom weight boxes by Fab-U-This

Penske shock

Revalved front forks

Heads Up Performance (Scott Horner) Triple Tree

Brocks Performance BST carbon fiber wheels

World Wide Bearings ceramic bearings

Brembo brake calipers, rotors, master cylinders

Ohlins steering damper

Air-Tech Streamlining fiberglass bodywork

Front fender Tiger Racing (Guy Caputo)




Engine built by Knecum Performance Engines

Tuned by Shane Tecklenburg

Custom JE Pistons

Custom Carillo Rods

Marine billet crankshaft

Undercut micro polished transmission with overdrive gears

Custom Webb camshafts

Coated bearings

Multi-stage lock up clutch

Billet basket

Stainless valves

HD valve springs

O ringed head

HD cam chain

Manual cam chain tensioner


Turbo System


Custom compound turbo system built by Steve Serafini from Fab-U-This

2 Comp Turbo triple ball bearing billet wheel turbos

2 Bell water-to-air inner coolers

3 Turbosmart wastegates

Turbosmart blow off valve

5 gallon custom ice tank

4 gallon custom fuel tank

Custom Fab-U-This water-to-air intake




Motec M800 ECU

Motec HD-VCS

Motec C-125 color display dashboard

AMS-2000 Boost controller

24 volt starting system

2 lithium ion batteries


Fuel System


NLR Waterman mechanical fuel pump

8 Injector Dynamics ID2000 injectors

Fragola fuel lines and fittings

48mm throttle bodies

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