The Rouserworks X Biltwell Spare Parts Sportster

The Rouserworks X Biltwell Spare Parts Sportster

El Diablo Run 2019 Down n' Dirty After Action Report Reading The Rouserworks X Biltwell Spare Parts Sportster 9 minutes Next Why Swap Meets Matter

In 2017, we built the Frijole 883 with the intent to be the first Harley-Davidson to finish the NORRA Mexican 1000. Durability and reliability was the focus along with keeping it looking like a Sportster. Just a bulletproof tractor. Our strategy paid off when we shocked the naysayers by not only finishing but crossing the line in Cabo at number 27 out of the 43 motorcycles that started the 2018 edition of the Mexican 1000.


Spare Parts Sportster

When preparing for NORRA, we built and bought every spare part we could think of. Desert racing rewards consistency and planning as much as skill and bravery. When you lack the latter, you definitely gotta stock up on the former. We built a complete replacement front end, five sets of wheels and tires, enough bars and controls to rebuild the bike each of four nights. We kinda overdid it and bought another Sportster a week before the race and stuffed the engine in the back of the van just in case. Over 1300 miles of racing later, the only carnage was squared two wheels, one cracked shift lever and a single worn out rear sprocket. I had previously told the team that if we didn’t finish, we would keep trying until we did. That might have helped motivate us as the long days wore on, and once we successfully crossed that finish line the decision was made to mothball the Frijole just as it was – still reeking of dead fish from the last sand wash and stale beer from the ceremonial chug on the podium. Seriously, it stinks like a weekend of bad decisions.

Spare Parts Sportster

When we got home and sorted out the chase trucks, we had an enormous amount of time-consuming and expensive leftovers. Might as well build another bike out of all this good stuff, right? The Spare Parts Sportster was born. We wanted a more finished look on this machine with more power and less curb weight. A lighter hot rod that works on and off-road and looks good doing it. Rob did 99% of the work on this build and I think the only thing I did was weld the pipe, pick a few colors, and help make a few decisions. Since most of the head-scratching was done on the original race bike, this one–even with more attention paid to aesthetic details–went together much quicker. The SPS is registered for the street, has brake lights and is slightly less over-built and definitely not as under-powered.

Spare Parts Sportster

After breaking in the freshly-built, S&S Hooligan kit equipped bike on the street, I have to say it’s my favorite Sportster of all time to ride. It rips, but is totally rideable in all conditions. I did 300 mile days on the street without feeling like I had been on a paint shaker or wound-out dirt bike. Rouser builds a tight machine and the overall feeling when riding it is “this could be a production bike”. No weird shakes, rattles, ergonomic compromises or other negatives. It’s still GP-style shifting and has a Rekluse clutch.

Spare Parts Sportster

Once it was broken in, our local buddy and factory MX test pilot Ricky Yorks got a chance to throw a leg over it and rip it around the backyard track at the Lapaglia family’s compound in Murrieta, California. As testimony to Ricky’s skills, right before he took off he said “You know, I think I rode a Harley around the block once because Otto made me. Other than that, I’ve never really ridden one”. The he proceeded to send it over the table, rip through the whoops on a bike twice the weight of what he’s used to and bombed the step-up. After an hour or so of him ripping the track, the bike was not much worse the wear and I rode it back home for an oil change and a once-over. The only casualty was the stock axle lollipop adjusters were starting to cave in since we didn’t beat reinforced wedges into the swingarm like we did with the Frijole. That will be remedied with another set from our friend Tim at GigaCycle Garage soon.

Spare Parts Sportster

Spare Parts Sportster

Spare Parts Sportster

So what now? Well, it’s a daily commuter now and we might race LA to Barstow to Vegas or the Mint 400 and then we are planning a trip to the Arctic on bikes for summer of 2020 and this is going to be Rouser’s ride. We’ll have to build a rack to hold some gear, repair anything that’s been hammered in the meantime but other than that, it’s ready to go and so are we!


Spare Parts Sportster

Spare Parts Sportster


Spare Parts Sportster

Spare Parts Sportster

Spare Parts Sportster

Spare Parts Sportster

Spare Parts Sportster

Spare Parts Sportster

Spare Parts Sportster

Spare Parts Sportster

Differences between the SPS & Frijole 883

Engine The Frijole 883 engine was kept an 883 in stock form with the exception of the valve covers, ignition system, oil pump, tweaked CV, and clutch.

The SPS got a complete 1200cc S&S Hooligan kit that consisted of pistons, rings, wrist-pins, clips, jugs, lifters, cams, and gaskets. As well as the rest of the stuff the Frijole got ie; valve covers, oil pump, clutch, ignition system, and tweaked CV.

The Frijole 883 air cleaner was overbuilt with 4 stages of filtering where the SPS received a standard Gasbox dog dish type air cleaner.

The Frijole 883 also had a catch can for trans and head breather oil mist, where the SPS breathers flow thru a mini Uni element to the atmosphere.

Exhaust is the same with the exception of the muffler. Frijole 883 has a tunable Supertrapp, SPS has a mini Cone Exhaust muffler.

Body The Frijole kept the stock tank and rear fender(trimmed) to keep the Sportster look.

The SPS got an aluminum Storz tank and an aluminum Tsunami Fender from Lowbrow Customs. Which gave it a racier look as well as lightened up the sheet metal weight.

The SPS also was set up without a rear rack, storage bags, or spare gas containers.

While the headlights were the same on both motos, SPS received a more modern headlight shroud.

Frijole 883 has no kickstand, SPS does

Electrics The SPS only received one battery and coil, where the Frijole received two batteries and coils for race redundancy. The SPS was also built sans a navigation system.

Tires The Frijole 883 was equipped with Nitro Mouse for durability and no flats during the race. SPS received 3mm Michelin tubes for more “street ability”

Seat The Frijole 883 seat was built as a “loaf” seat for maximum comfort and height.

SPS seat was built slimmer, and narrower for more eye appeal but remained functional for a “dual purpose” moto.

Gearing The Frijole 883 had to be geared with a giant “pizza” rear sprocket to move the power band lower in the RPM range to help the tiny 40-something horse power motor make it thru the loose sand of Baja.(forgot the tooth count?)

SPS has “normal” streatable gearing

Controls The foot pegs are the main difference, Frijole 883 received true MX footpegs for riding with motocross boots and the SPS got a prototype set of Biltwell Punisher pegs. We also did more reinforcing on the right side foot control mount on the Frijole, where on the SPS we only added our own bushings, brake pedal and some slight modifications to the peg mounts provided by Hugo Moto.

SPS Spec Sheet

Moto Model

  • 2003 XL883
  • 3,400 miles

Engine Mods

  • S&S 1200cc
  • Hooligan kit
  • Rouser tweaked CV w/Mikuni choke cable
  • Gasbox air cleaner
  • Hi-scavenging oil pump
  • Buell XB valve covers & breathers
  • Rekluse clutch kit
  • Custom exhaust w/Cone Eng. muffler & Jet-Hot coating


  • PBI front & rear sprockets
  • EK 530 non o-ring chain
  • Jim’s Meganut
  • Delrin chain roller w/ceramic bearings
  • Big Twin primary adjuster shoe as swingarm slider

Frame & Swingarm

  • Added welds to strengthen motor mounts
  • Lower motor mount aluminum cross brace
  • Rear fender struts shortened
  • Reinforced oil tank w/added mounts & screw on cap
  • Gasbox battery mount
  • Reinforced swingarm by Doug Roll


  • 2005 CRF250R front caliper & master cylinder
  • 2003 XL883 rear master cylinder
  • Tokico 4 piston rear caliper
  • GigaCycle rear brake caliper carrier
  • EBC disks & pads f&r
  • Stainless brake lines f&r
  • DOT5 brake fluid f&r


  • 2005 CRF250R front forks & bottom tree
  • GigaCycle top tree & stem
  • GPR stabilizer
  • Cannon front springs
  • Precision Concepts built & tuned front forks
  • Elka rear shocks
  • Doug Roll built & tuned rear shocks


  • Pro Taper Adv bars
  • Fastway risers
  • Cycra hand guards
  • Motion Pro throttle & cables
  • Motion Pro clutch perch
  • ARC levers
  • Biltwell Thruster grips
  • Hugo Moto foot control relocation kit
  • Biltwell prototype pegs
  • Custom rear brake lever w/Alloy Art folding peg
  • Custom shift lever w/Alloy Art folding peg (setup GP style)
  • 2003 XR400R kickstand

Wheels & Tires

  • 2005 CRF250R front hub
  • 2003 XL883 rear hub
  • Buchanan SS spokes
  • SUN rims 18” rear, 21” front
  • Maxxis Desert IT tires f&r
  • Michelin 3mm tubes f&r
  • Counteract balance beads


  • Dyna 2000i ignition
  • Dyna Twin Fire Coil
  • Dynatek custom plug wire kit
  • Cycle Electrics regulator
  • Antigravity battery
  • K4 circuit breakers & switches
  • Ride Eng. starter button


  • Storz tank
  • Lowbrow Tsunami rear fender
  • 2005 CRF250R front fender
  • Duane Ballard seat foam
  • Motoseats seat cover
  • Biltwell license plate mount


  • Baja Designs Squadron Pro LED headlight
  • Biltwell Bullet tail lights


  • Hugo Moto skid plate (reinforced welded w/added glide skin)
  • Regulator shield

Paint & Plating

  • Paint & pinstripe by Pete “Hot Dog” Finlan
  • Ceracote by Natural Selections
  • Scotchbrite by USA Metal Polishing

Spare Parts Sportster