Sick Customs’ 1989 Harley-Davidson FXRT

A lot has been done with Harley-Davidson V-Twins over the years, so it takes some effort to customize a Harley today that really stands out. Jack Reigelsperger of Sick Customs thought outside the box with this build of a 1989 Harley-Davidson FXRT. See for yourself what makes it unique!

Sick Customs in Phoenix first opened its doors back in 2009, but founder Jack Reigelsperger’s obsession with performance started before he was even old enough to drive. “As a kid, I used to hang out in an old hot rod shop,” Reigelsperger says. “I’d sweep the floors, and when the shop was clean, they’d let me work on some of the cars. Back then, that was tech school.”

Today, Reigelsperger’s shop, Sick Customs, is a classic automotive shop that creates custom vehicles, boats, motorcycles, and off-road toys.

1989 Harley-Davidson FXRT customized by Jack Reigelsperger of Sick Customs in Phoenix.

“This business is not a job to me, it’s a lifestyle,” he states. “I enjoy combining the best of old school aesthetics with modern touches that improve both performance and drivability. We like to see people using these things.”

That philosophy was part of the deal when Reigelsperger decided to build the ultimate ‘80s Harley street cruiser. With this project, Jack says he wanted to build a bike that ticked every box for him, both aesthetically and mechanically.

“I was basically looking to build a motorcycle that had everything I wanted on it,” he says. “It’s completely custom from front to back.”

He selected a 1989 Harley-Davidson FXRT for the project and set to work making his vision a reality, equipping the bike with radial brakes, a hand-made, one-piece front fairing to replace the factory two-piece design, suspension upgrades, and of course a wild custom paint job.

“And performance was a must,” he says. “We did a 113 cid V-Twin with an oil-less Comp turbo – we just kind of remote-mounted it underneath the fairing so it’s kind of hidden.”

Outfitted with forged internals and running 8-lbs. of boost, the V-Twin dishes out about 180 horsepower, which is more than enough to get the 600-lb. Harley moving in a hurry. Still, Reigelsperger felt like the bike needed something more to help separate it from the pack.

“We like to think out of the box – do things that no one else is doing,” he says. “We always want there to be a ‘wow factor,’ and turbo bikes are becoming more and more common these days. But nobody has been running oil-less turbos on older bikes because it’s a newer technology and it’s tough to figure out how make the fuel injection system work with them.”

That gave him an idea to do something that nobody’s ever seen – flipping a Sniper EFI system on its side and seeing if he could make it work. Reigelsperger selected a Holley Super Sniper EFI 2300 for the job, as it offered the boost reference MAP sensors he needed and its four 100-lb. per hour injectors would be able to keep up with the boosted V-Twin’s fueling demands.

However, considering the fact that the system had never been adapted to a vintage Harley before, he knew he’d inevitably run into a few challenges along the way.

“One of the bigger ones was just making sure that it could function properly on its side,” he noted. “We added some extra bracketry and made a custom aluminum intake for it, and we made a cutout up underneath the tank so we could mount the high pressure fuel pumps.”

He also pointed out that the Sniper system offered tuning functions that go well beyond a factory-style setup.

“With the turbo system, I wanted something that I could change on the fly,” he says. “The Sniper system is very tuner-friendly, and it allows us to make changes while we drive for various situations.”

Even still, there was a fair amount of custom work that needed to be done in order to get everything to work in harmony such as an aluminum flange for the throttle body that was adapted to a factory Harley intake.

“Getting the depth dialed in was tricky – I think we went through four prototypes before we nailed it,” Reigelsperger says. “We also needed to put together that high pressure fuel system with a return – most Harleys don’t have return lines or anything like that.”

On the software side, Sick Customs used the Sniper system’s baseline tune to get the engine up and running so its self-tuning features could help get things sorted out, then made some manual tweaks from there.

“There were a couple of places where the Sniper wouldn’t want to make changes, so we went into the Holley EFI software, made some modifications, and then applied those changes to the system,” he says. “This wasn’t really designed for a two-cylinder engine, so the tweaks we needed to make were about getting it to work in this unusual application to keep it from over-fueling.”

With those custom parameters dialed in, Reigelsperger says the Sniper EFI retrofit has significantly improved the riding experience.

“The power delivery is very smooth, and the response is so much sharper because it’s running the correct air/fuel ratio all the time,” he says. “When that boost comes on, it’s just… ‘you better hold on.’ Normally, if you’re cruising on a turbo bike that’s off-boost and you grab the throttle, the fuel injection systems on most of the Harleys will kind of choke up for a second. But, with the Sniper’s live adjustment, that just doesn’t happen – it responds instantly no matter where you are in the rev range.”

While the project is still in the final stages of development, Sick Customs is already looking into where Sniper EFI can provide big benefits in other applications.

“We’re actually building two other bikes with Sniper systems right now,” Reigelsperger says. “And we’ve been looking into newer Harley engines like the M8 as well. The tunability opens up a lot of options that the factory EFI won’t give you – like the ability to make street and track-specific tunes that you can switch between whenever you need to. It allows us to take these bikes to levels that Harley’s fuel injection systems just can’t do.”

With more than a few ‘sick’ custom touches, this is now one cool Harley FXRT that 1989 could have never imagined. *Thanks to Holley for the original article*

If you have a motorcycle, ATV, UTV, snowmobile or jet ski you’d like to feature in MPN’s Ride of the Week series, please email MPN Editorial Director Greg Jones at [email protected].

You May Also Like

2025 Beta Xtrainer Model

The number-one-selling entry-level enduro bike.


As the Beta Xtrainer begins its 11th year of production, it is being celebrated with a stunning new look featuring grey bodywork to compliment the Italian red frame. The new look separates the look from its cousins, the RR X-Pro and RR Race Edition models.

The Xtrainer has been the number-one selling entry-level enduro bike in many countries; this is no surprise due to the ease of riding compared to larger, bulkier enduro models. The bike's overall smaller chassis, low seat height and overall weight make the bike perfect for not only entry-level enduro riding but also as a perfect model for those wanting a second bike for play.

Custom Kawasaki KZ400 Motorcycle

Zane Cook’s custom Kawasaki KZ400 certainly turns heads. We have the details of this custom motorcycle creation in our Ride of the Week brought to you by Gryphon, a family run motorcycle protective clothing company offering style, function and protection. See the full line of apparel at https://www.gryphonmoto.com/ Related Articles – Revival Cycles’ Custom Honda

Revival Cycles’ Custom Honda FT500 Ascot Motorcycle

This custom Honda FT500 Ascot from Revival Cycles turned an ordinary motorcycle into something extraordinary. It’s also our Ride of the Week brought to you by Gryphon, a family run motorcycle protective clothing company offering style, function and protection. See the full line of apparel at https://www.gryphonmoto.com/ Related Articles – Brough Superior AMB 001 Limited

Custom 2022 Polaris RZR Pro R 4

Dave “Heavy D” Sparks of Diesel Brothers fame, has plenty of other hobbies outside of the diesel world, such as dune buggies. That passion for off-road playgrounds lead him to build this custom 2022 Polaris RZR Pro R 4 featuring classic LeMans livery. The UTV was on display during Camp RZR, and its our Ride

Lord Drake Kustoms’ BMW K1 Racer

Anyone familiar with Lord Drake Kustoms will know they make some amazing custom motorcycle creations, and this BMW K1 is no exception. Hear the full details in this Ride of the Week brought to you by Gryphon, a family run motorcycle protective clothing company offering style, function and protection. See the full line of apparel

Other Posts

AMSOIL Adds 5W-40 Synthetic Metric Motorcycle Oil

Crafted for optimal performance in four-stroke sport, cruiser, adventure and touring bikes.

Ducati and Supreme Create Collectors’ Edition Line

A new, limited-edition Streetfighter V4 S with a custom livery created by Supreme and Aldo Drudi of Drudi Performance.

A Better Way to Ride a Motorcycle

A recent study predicts realistic motorcycle riding behaviors while considering human factors and ergonomic trade-offs.

Scrambler Reveals 2 Concepts at the Bike Shed MotoShow

The Centro Stile Ducati reinterprets the new Scrambler with two surprising concepts to inspire the public at the London event.