Buell XB12S Lightning - something completely different
By Mike Hanlon
January 20, 2004
The Buell XB12 Lighting is quite unlike any other roadgoing motorcycle, though it draws a logical comparison with the Cagiva Xtraraptor and Ducati Monster. All three involve massive fuel-injected v-twin motors with minimalistic styling, but the Buell does it differently … very differently. For starters, it has 20% more engine capacity, and produces more torque delivered lower in the rev range than its competitors. The real trickery behind the Buell is not the engine though – it is the radical forged aluminium chassis. The fruit of countless hours of computer simulation of the stresses which motorcycle chassis’ undergo, it is as rigid as it looks, and doubles duty as a petrol tank, while the massive swinging arm also multi-tasks as the oil tank.
In this way, the entire package has been made smaller and lighter. So with the biggest motor in a class of motorcycle known as “streetfighters”, the brutal Buell is also the smallest and lightest of the bunch. On the road, it feels a lot smaller and lighter and more nimble than its competitors, but comparing the numbers really highlights the magnitude of Buell’s achievement.
The XB12 weighs 10% less than the Italians and its wheelbase is 1320mm compared with 1440mm for the Ducati and Cagiva. A 10% difference in the wheelbase of a motorcycle translates to a very different riding experience. It also has a steep 21 degree rake (steering head angle) and a compact, low centre of gravity, and this helps to understand how Buell have created a motorcycle with such a difference.
The fighting weight of the Buell is quite remarkable at an anorexic 175 kg, compared to the Monster’s 193 kilos and the Xtraraptor’s 197kg. Compare those weights with Honda’s all-conquering MotogGP bike which should sit on the 145kg minimum but doesn’t, weighing in at “more than 148 kg” according to official documents.
No weight has yet been specified for the first of the MotoGP replicas likely to hit showroom floors – the Ducati Desmosedici RR. The real Desmosedici weighs in at 145 kilograms, right on the MotoGP limit. It will be interesting to see which is lighter – the Buell or the RR.
Now Ducati and Honda don’t have to worry about head and tail lights, blinkers, mirrors, instrumentation, alternators and batteries and all the other road registrable paraphernalia on their GP bikes. Both are constructed of materials which could not be considered in mass production due to their limited lifespan and incredible cost. Buell’s delivery of a road bike which is so close in weight to the fastest GP bike in history is a feat of some magnitude. That’s how it can be both brutal and surgical at the same time. It stalks down the street, with the feeling that it is applying more rubber to the road than a Formula One car. Yet the wheels are both several kilograms lighter than the competition, and such a substantial reduction in unsprung weight enables the suspension to do its job so much better.
The suspension is made by Showa, the same company which provides the suspension on the aforementioned RC211V Honda MotoGP machine, with both ends adjustable for preload, compression and rebound damping and a set of upside-down forks which further reduce unsprung weight. Inverted forks are state-of-the-art these days, gracing every tarmac machine with sporting pretence from MotoGP to supersport roadsters but Buell was the first to fit inverted forks to a roadgoing motorcycle. With quality suspension, an incredibly rigid chassis and the lightest unsprung weight in the business, those fat sticky tyres stay glued to the tarmac and the XB12S offers a comforting grip on the road in all circumstances.
Most notably, the Buell feels at home under brakes and that’s probably due to the patented Zero Tortional Load (ZTL) braking system. The 375mm perimeter mounted rotor is gripped by a six-piston Nissin brake calipre and offers immense power and delicate feel. You won’t run out of brakes on the Buell, and alongside the Aprilia RS250, you will never get a safer motorcycle upon which to refine the “art of the stoppie”, the spectacular under-brakes, reverse wheelie made famous by stunt bikers.
Read the numbers and you know it steers quickly even before throwing a leg over the low saddle. But with such miniscule proportions and shallow rake, one would expect far twitchier, overly sensitive steering than the XB12S delivers. It feels agile and poised, not skittish and not at all threatening as some bikes of similar proportions do.
We suspect that one of the key reasons for the Buell’s poise and lack of any disappointing road manners is what we previously referred to as a compact centre-of-gravity – the average location of the mass of the motorcycle.
The compact design of the Buell is doubly clever when you consider how it has rearranged the components in order to get the heaviest items closer to the centre of gravity – the muffler, petrol and oil tanks being the obvious targets, but even the truncated rear-end styling saves valuable weight at the extremities.
The Buell is the product of 20 years of refinement under the funding of Harley Davidson motorcycles by Erik Buell. Originally Buell pursued dreams of building prototype race machinery leading-edge limited-edition sportsbikes.
The first motorcycle designed and built by Erik Buell was the RW750 in 1983. This was a 750cc, two-stroke, “square-four”, rotary-valve racing machine designed specifically to compete in the AMA Formula One road racing class.
A prototype RW750 first hit the track in the AMA National at Pocono Speedway in the summer of 1983. Buell continued extensive testing and development work on the bike throughout that summer and into the fall. His success was measured during testing at Talladega, Alabama, where it was clocked at a top speed of 178 mph. Development on the RW750 continued through 1984, a production version was released in the fall. Just one RW750 was sold to the American Machinists Racing Team before the AMA announced that 1985 would be the last year of Formula One racing. An announcement that Superbikes would occupy the premier race class in 1986 effectively eliminated any market for the RW750. Crushing as that may have been to lesser builders, Buell viewed the rules change simply as a setback. He went back to work, this time aiming squarely at the goal of building the first world-class sportbike designed and built in the USA. Tapping his knowledge of what works on the racetrack and his experience as a Harley-Davidson engineer, Erik Buell designed his first entry into the sportbike market, the RR1000. Powered by the Harley-Davidson XR1000 engine, the stiff, light chassis was designed to allow rubber-mounting that became a patented engineering “trademark” of Buell sport bikes: the Uniplanar system. Buell’s design also utilised the engine as a fully stressed member of the frame. Capping the engineering firsts was Buell’s use of a rear suspension mounted beneath the motor and a shock that operated in reverse of the conventional compression-rebound practice. A total of 50 RR1000 models were produced during 1987-88 before the remaining XR1000 engines were depleted.
Buell saw the new 1203cc Harley-Davidson Evolution engine as an opportunity to continue tuning the performance and handling qualities of his bikes. With that in mind, he began redesigning the chassis to accommodate the 1203. The resulting RR1200 model was introduced during 1988, and 65 were produced for sale through 1989. Streamlining and bodywork had been a particular talent and passion for Erik Buell. Thus, his motorcycles continued to change at a measured pace through the years. In 1989, he introduced the RS1200, a two-seat version of the RR model for riders who demanded both world-class performance and two-up comfort. 105 of these unique models were produced through 1990.
Five-speed transmissions were a new feature of the 1203cc engine in 1991. Buell responded to revised engine mounting points with further design improvements to the RS chassis. These bikes were the first production motorcycles to use “upside-down” (inverted) front forks, stainless steel braided brake lines and a six-piston front brake calliper.
As Buell motorcycles were refined, the company’s manufacturing capabilities were expanded. 1991 was the first year in which Buell Motor Company not only designed bodywork, but also produced it in a new composite and paint shop. The result was greater quality control and improved design flexibility.
A single-seat version of the RS1200 was introduced late in the 1991 model year. Dubbed the RSS1200, it won enthusiastic approval of the motorcycle press for its lean, clean lines. A total of 40 units were built between March and August 1991. Combined production of RSS and RS models totalled 325 through 1993. In 1994, Buell introduced the curvaceous Thunderbolt S2, the first model produced under the partnership with Harley-Davidson Inc. The motorcycle won rave reviews from the motorcycle press and is still known for its beautiful lines and fluid design. A sport-touring version, the S2T, was added to the line-up in 1995. The new model was named Rider Magazine’s Top Innovation that season. Together, the two models combined for total sales in excess of 1,000 units. The next year brought the introduction of the all-new 1996 Lightning S1. The original “street fighter”, the Lightning S1, defined a whole new class of “Hooligan” motorcycles. Featuring minimal bodywork, a racing-styled seat, exposed frame and the centralised mass of the 1203cc engine, exhaust system and suspension, the model was named “Hooligan Bike of the Year” by Cycle World Magazine that year.
A redesign of the Thunderbolt was also introduced in 1996 as the Thunderbolt S3 and the Thunderbolt S3T. The models continued the design evolution of sport touring motorcycles. Together with the Lightning S1, the S3 and S3T combined for sales in excess of 2,000 units.
In 1997, the Cyclone M2 was introduced to the Buell line with ith a more relaxed seating configuration and wider seat, the Cyclone helped push Buell motorcycle sales above the 3,000 unit mark. The new Thunderstorm engine was introduced into the Buell line-up in 1998 as the powerplant for the new White Lightning S1W model. Similar in styling to the S1 Lightning, the new bike featured a carbon fibre rear fender, bold colours, and the super-high output Thunderstorm engine. The S1W was named “Best Standard” by Cycle World Magazine. The Thunderbolt models also received the Thunderstorm engine to round out an impressive offering of 1998 models. Sales continued to grow, and in 1998 Buell sold more than 5,000 motorcycles. A complete redesign of the Lightning and Cyclone models was in store for 1999. New body, new frame, new suspension, larger and more comfortable seats and bold new colour offerings were available on the Lightning X1 and Cyclone M2. The Thunderbolt S3 and S3T also received a refined seat and dramatic new colour and sport touring options. Dynamic Digital Fuel Injection (DDFI) became a standard feature on the Lightning and Thunderbolt as well. The redesign and refinements helped contribute to total sales of approximately 8,000 units world-wide during 1999.
On the road
Now the centre of gravity of a motorcycle is just the average location of the mass of a motorcycle.
One of the main reasons big touring bikes wallow and yaw on undulating and bumpy roads at speed is the amount of weight they carry at a distance from the centre of gravity – panniers, a heavy fairing, a top box and heavy mufflers all contribute to the shimmy and yaw to warn the rider that any more power or speed or unwanted road forces might cause the motorcycle to samba out of control. The Buell is at the opposite end of the scale, with every fitting on the motorcycle designed to be as close to the centre of gravity as possible – it is the exact opposite and reduces the moment of inertia in pitch, roll and yaw. The result is a bike which is effectively devoid of bad handling behaviour – if you are good enough, this bike will do exactly what you tell it. If you crash this bike, it will almost certainly be because you have been going ridiculously fast or have misjudged the road surface.
The seating position is quite upright, and the bars are flat and offer plenty of leverage, so the bike is ideal for round-town and won’t give you a sore back. In discussing the handling and road presence of the Buell, it was more than once described as a bionic pea – it feels like it has a compact core which sits directly below the rider located somewhere between the knees and ankles and with such an upright seating position and the bike disappearing below the rider’s view very quickly, it feels like it will do whatever is asked of it, and inspires confidence. The Buell press kit describes it as a “feeling of flight” and it’s not just the product of a copywriter’s imagination – it really does feel different and exhilarating.
Now the XB12S motor arguably has its roots a half century in the prehistoric past given the rate of engine evolution going on around it. The Harley motor is not remotely near the forefront of engine design though it does a remarkably good job thanks to the addition of a range of innovative solutions and modern technology grafts which have taken well.
It looks and sounds like a two-wheeled, big bore hotrod motor and its specs share more in common with a fuel-injected V8 hotrod than they do with the overhead camshaft and sophisticated valve actuation of its much higher revving competitors.
The air-cooled, 45-degree pushrod twin is now fuel-injected but it snarls and spits just like the hot rods it emulates. That’s not to say there isn’t some very clever stuff happening. To keep the torque band fat, the new XB1200 engine is equipped with Buell InterActive Exhaust. An electronic actuator activates a butterfly valve housed in the muffler to adjust back-pressure by alternating between two gas flow paths. The engine ECM monitors engine speed and throttle position while activating the valve to optimise torque and horsepower for the riding condition. At wide-open throttle, for example, the valve is opened at low rpm to reduce back-pressure so the engine can gain rpm quickly. The valve closes in the mid-range to increase torque during acceleration, and then opens again at high rpm to deliver the most horsepower.
The Buell InterActive Exhaust has a rich, throaty exhaust note – open the throttle and the rumble of idle becomes a flat blat which takes on a rich tonal quality in the mid range. The motor is at its finest with an open throttle and between 3000 and 4000 rpm on the dial – it’s not your standard Harley drag-pipe music but it fits nicely with the feeling of the bike and with a 1200cc motor in the midst of its torque curve, the XB1200S simply beams you to a different speed.
That’s why the Buell is so rewarding. It can be ridden around town in a completely legal manner whilst having more fun than you can imagine – this is not possible on a 1000cc supersport. On the Buell, it’s just big grin territory.
If it were our choice, we’d get a set of cams to take 25% off the 100 horsepower top end, fattening up the low and mid-range torque curves in the bargain. And we’d fit heavier cranks so it is smoother at low speed, where it’s willingness to cough and spit necessitates one watchful hand over the clutch at all times. It’s current state-of-tune detracts from its low speed engine performance just a little too much.
Outside city limits, the XB12S is a happy participant, though it’s more a backroad motorcycle than a freeway machine. There’s no fairing and like all naked bikes, it gives you a full frontal to the elements. If your Buell is going to see a lot of country roads, and wind roar and buffeting aren’t your go, then choose the XB12S’ similar but faired variant, XB12R.
On a windy road the frame and suspension make light of every corner, setting you up for the surge of torque and glorious ripping exhaust as you slingshot from the exit of every turn. It’s fantastic fun in these environments, and more than makes up for the discomfort of riding it into the country on a freeway.
But it is a streetfighter-class motorcycle first and foremost - an immensely capable almost miniscule motorcycle with a relaxed, ergonomically-sound riding position designed for an urban environment.
Ride it well and it rewards you. Ride it badly and the big motor excuses almost any faux pas. It is incredibly responsive, and can be pulled in tight in the middle of a corner without any sign of a complaint. Unlike most bikes this tiny, which have high-revving 125 and 250 motors, it’s very difficult to find yourself in the wrong gear, and if you do, get on the clutch and feed in some drive and the big motor will snap you upright again.
A thoroughbred motorcycle it is. Yet for all its charms, one stands out above the others - it has a personality. In a world of sameness, it is very different and it’s a bike you will enjoy being with. If you’re prepared to wear a backpack or have it wear a tankbag, you could ride it to work every day and enjoy doing so every single day. It’s a bike upon which you can have fun at the speed limit.
There’s one final aspect of the Buell which might make a difference. It has limited availability, distinctive styling, and a two great brand names behind it, one with a 20 year heritage and the other with a century. It will always retain a strong resale value.