In 1988, Ducati unleashed the Desmoquattro 851 engine, the first desmodromic twin with liquid-cooling, four valves per cylinder, and electronic fuel injection. The engine found its way into one of the iconic sports bikes of the era, the 851 Tricolore, a homologation special that boasted 102 hp and a dry weight of 204 kg (450 lbs).
“World Superbike racers were required to be based on production streetbikes. One way to get the highest-specification base model possible was to build homologation specials — expensive, limited-edition versions that needed relatively minor modification to be track-ready. Ducati took this so-called ‘kit bike’ approach with the 851 Superbike. Just 207 of these nominally street-legal machines were hand-built, enough to satisfy World Superbike rules, with an estimated 20 examples coming to the U.S.” –Bonhams
The racer would prove its mettle in World Superbike, where the 851 and its derivatives took home 11 manufacturers’ titles over the next decade and a half.
Our friend Pepo Rosell, the world-class builder behind XTR Pepo and an aficionado of vintage endurance racers and superbikes, had been wanting to build an 851 for quite some time. Finally, the right project arrived.
“This bike is a commission from a guy who wanted to race in Classic Endurance races. The rules allowed the use of bikes from the late 80’s to the early 90’s and the 851 was right there. For a long time I’ve wanted to build an optimized 851 and bingo this guy asked me to make one.”
From the beginning, Pepo’s vision was clear — an 851-inspired machine with a more modern, powerful, and reliable engine like that of the 999. As it would be prohibitively expensive and possibly wicked to cut up an original 851, Pepo decided to start nearly from scratch:
“As finding an original Ducati 851 to work on was very difficult and expensive, I decided to ‘work from zero,’ using a Ducati Monster 600 (carbureted) frame…”
Pepo modified the Monster 600 frame to 851 specs, then fitted a blueprinted Monster S4Rs (999 Coppa Bassa) engine that boasts a lightweight flywheel, slipper clutch, high-flow airbox, and other mods. (These Coppa Bassa or “Low Cup” superbike engines provided better lubrication at extreme angles of lean.) The bike is rolling on a set of Ducati ST3 wheels and adjustable forks with Brembo brakes, Continental Race Attack rubber, and a YSS rear shock custom-built for the bike.
The tail section is an 888 solo unit with XTR custom upholstery, while the front fairing is an 851 model modified to run a Cagiva Mito 125 Lawson replica headlight. The tank is an 851 fiberglass unit with quick-release fillers and a transparent strip for reading the fuel level. The list goes on…a full build sheet is included below.
Pepo says the bike has a dry weight of just 165.8 kilograms (~365 lbs) — around 85 pounds lighter than the original!
As for the livery, there’s no mistaking the inspiration — the same proud colors as those of the Italian flag.
“I was tired of red bodywork and white frames (it’s so typical), so I wanted to make a tribute to the first 851, the Tricolore.”
Leaning on his deep knowledge of racing history and unbeatable eye for detail, Pepo has created a Ducati Tricolore custom that’s not only a tribute to the iconic original, but unmistakably XTR in execution. Bravissimo, Pepo!
Build Sheet: XTR Tricolore
- Donor Bike: Project made from zero starting with a ’94 Ducati Monster 600 frame
- Modified Ducati Monster 600 frame to Ducati 851 specification
- Fabrication of reinforced frame parts to strengthen the chassis
- Fabrication of rear subframe fittings.
- VS Frame 851 aluminium rear subframe
- Ducati Monster 600 swingarm
- YSS Adjustable rear shock made specifically for the bike
- Aluminium rear suspension rocker lightened
- XTR carbon fiber rear mudguard
- Ducati ST3 rear wheel
- Brembo rear brake rotor
- Brembo rear brake caliper
- Alluminium adjustable rear brake rod
- Frentubo kevlar rear brake line
- Brembo rear brake pump
- Ducabike adjustable CNC-machined footrests
- Ducati Monster S4Rs Engine (999 Coppa Bassa)
- Engine Tuning:
- Aluminium TSS light flywheel, complete dismount and change of all bearings, bushings, shims, etc. Blueprinted remount.
- Slipper clutch
- 999 injector body
- XTR high volume airbox
- Walbro external fuel pump
- Fuel pressure regulator
- Electrics:
- 998 racing wiring
- ECU mapping
- Separate electric devices wiring (rear and front lights, fan)
- Lipo Battery
- AviaCompositi dashboard with lap timer
- Double LED rear light
- Cagiva Mito 125 Lawson replica front light
- RC Radiator (High capacity racing radiator)
- Aluminium water tubes
- Radiatior fan
- Ducati 999 oil radiator
- Ducati Monster 900 yokes
- Ducati ST3 adjustable front fork
- XTR CNC-machined clip-ons
- Ducati ST3 front wheel
- Brembo front brake calipers (4 pads)
- EBC sinterized brake pads
- Discacciati lightened floating front brake rotors (5mm thickness)
- Frentubo kevlar brake lines
- Ducati 1098 Front Brake Pump With Xtr Foldable And Regulable Lever
- Ducati 1098 Clutch Pump With Xtr Foldable And Regulable Lever
- Frentubo Kevlar Clutch Line
- XTR Aluminium front fairing bracket
- Sil Motor Roche Replica carbon fiber silencers with Spagheti exhaust system modified to fit 999 Coppa Bassa engine
- JT lightened Z14 sprocket, 520
- PBR Z 37 rear sprocket, 520
- Regina Gold 520 chain
- Modified Ducati Diavel sprocket cover
- DNA oil pressure air filter
- Ducati 888 rear solo seat
- XTR handmade seat and upholstery
- XTR / Ducati 851 fiberglass fuel tank with quick-open double gas fillers and transparent fuel level
- Ducati 851 fairing modified to mount the endurance front light
- Ducati 851 windshield
- XTR Aluminium fairing brackets
- Ducati 1098 front mudguard
- Domino quick-turn throttle
- Domino Soft Grips
- Continental Tires 120/70 – 17 and 180/55 – 17 Race Attack 2
- Artenruta Painting: Tribute to the first Ducati 851 Tricolore
- Powder Coating: chrome colour frame
- Dry Weight (no fuel) with water, battery, oil, hydraulic fluid, and air in the tires: 165 Kg, 800 grams
Detail Shots
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Pictures by Sergio Cardeña
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