| MODEL | BUELL X1 LIGHTNING 1999 |
| Year | 1999 |
| Engine Type | 45-degree V-twin, four-stroke, pushrod OHV, hydraulic self-adjusting lifters, 2 valves per cylinder |
| Displacement / Capacity | 1203 cc / 73.4 cu in |
| Bore X Stroke | 88.8 x 96.8 mm |
| Compression Ratio | 10.0:1 |
| Cooling System | Air |
| Max Power | 64.2 kW / 88 hp @ 6300 rpm |
| Max Torque | 104 Nm / 76.7 lb-ft @ 5600 rpm |
| Ignition | Electronic |
| Induction | Dynamic Digital Fuel Injection |
| Start System | Electric |
| TRANSMISSION SPECS | |
| Lubrication | Dry sump |
| Gear Box | 5-speed |
| Clutch | — |
| Final Drive | Kevlar belt |
| CHASSIS SPECS | |
| Frame | — |
| Front Suspension | 41 mm Showa inverted fork, adjustable compression and rebound damping |
| Rear Suspension | Showa shock under the engine, adjustable spring preload, compression and rebound damping |
| Front Brakes | Single 340 mm disc, 6-piston caliper |
| Rear Brakes | Single 230 mm disc, 1-piston caliper |
| DIMENSION SPECS | |
| Overall Length | — |
| Overall Width | — |
| Overall Height | — |
| Seat Height | — |
| Wheelbase | 1410 mm / 55.5 in |
| Ground Clearance | — |
| Dry Weight | 200 kg / 440 lb |
| Wet Weight | — |
| WHEEL SPECS | |
| Front Tyre | 120/70-17 |
| Rear Tyre | 170/60-17 |
| FUEL SYSTEM | |
| Fuel Capacity | 15.8 Litres / 4.2 US gal |
| Fuel Consumption | — |
| Top Speed | 225 km/h / 140 mph |
The X1 Lightning arrived in late 1998 as a heavily reworked successor to the S1, addressing its cramped seat, bulky airbox and rear-cylinder heat. It got fuel injection, Thunderstorm heads, a stiffer frame with aluminium subframe and swingarm, and fresh styling. Reviewers found it smoother and stronger in the midrange.
