Skip to Content

Buell XB12R Firebolt – American Sportsbike

The Buell XB12R Firebolt was ready for sale by early 2004 and while nearly identical to the XB9R it had at its heart a 1203cc V-twin motor. The two models ran side by side for the first year, before the XB9R was dropped from the range.  

Now, it’s no secret in the motorcycle world that Buells are divisive. 

Some love them and some despise them but the fact is they exist and if you can see past issues such as dubious reliability and accept that the ride may not be perfect, then they are pretty damn cool. 

Are they as slick as Japanese sportsbikes, or as visually pretty as Italian superbikes coming out of the Ducati and MV Agusta runways? No. 

They are Buells and they are a completely different breed from anything else. 

Let’s take an in depth look at the Firebolt XB12R. After all, if a motorcycle is divisive it usually means it has something going for it, to make it worth discussing. Nobody talks about beige boring machines and any Buell motorcycle is far from boring.

Buell XB12R Firebolt Review

Buell XB12R Firebolt


Erik Buell was an ex-Harley Davidson engineer who branched out and set up Buell Motorcycles in 1983. 

10 years later HD bought a 49% share of the company and another decade later HD owned Buell totally. By 2009 Buell was discontinued by HD and Erik Buell set up Erik Buell Racing which was a separate company focusing on race bikes only. 

During Buell’s reign under HD until 2009, 136,923 motorcycles were produced. 

At the time of the XB series release Buell only had the Blast model in production which was their only model to use a single-cylinder engine. It had a 492cc displacement and was often looked at as a learner model, utilised in HD’s riding schools.  

The XB range was to take over from models such as the X1 Lightning, S3 Thunderbolt and M2 Cyclone. A combination of straight sportsbikes and sports-tourers.

The XB series intended to push boundaries of what a sportsbike could do with a Harley powertrain. 

The XB models were the first in the industry to receive ZTL (Zero Torsional Load) perimeter floating front disc brake systems and they pioneered the use of the swingarm as an oil tank. 

Harley Davidson had big expectations for the new breed of Buell motorcycles. 

Let’s get to the nitty gritty by first taking a look at the engine and transmission of the Buell Firebolt XB12R.

Engine and Transmission

The XB V twin engine was still fundamentally a Harley Sportster engine and it had been designed for both the Buell XB9/12 and the latest iteration of HD’s Sportster. 

Harley Davidson took the lead on the engine design with little input from Buell.

Aerocharger were supposed to supply a turbocharger. This would have increased the maximum horsepower to 150hp.

However, the deal never went through and HD decided to engineer one in house. This was a project that never caught traction and eventually fell through. 

XB12 engines had a capacity of 1,203cc and had a longer stroke of 96.82mm over the XB9’s 79.38mm; the bore size between both engines was identical. 

The engine feels lumpy, it feels like a HD twin of days gone by. 

It is not refined or particularly smooth, and doesn’t have a mind-blowing top end but it has plenty of torque, loves and needs to be worked, and will throw you in and out of corners all day long to immense satisfaction.

Power is instantaneous, although not threatening, the grunt is enough to keep you from having to constantly work through the gearbox. 

Big cylinders are the sources of the masses of torque, but the linear powerband is due largely to the Buell Interactive Exhaust system. 

An electronic actuator activates a butterfly valve in the muffler to adjust back-pressure, this is done by alternating between two exhaust gas flow paths.

The engine computer monitors throttle position and engine speed to activate the valve and optimize torque and horsepower for the correct riding conditions. Quite a clever bit of a kit, not revolutionary but still a nice touch from Buell.

The intake throttle body and header pipe diameter was increased for the XB12R, a stiffer clutch spring was implemented and a stronger belt to handle the increased torque from the bigger capacity engine. 

To give credit where it is due, the engine is relatively smooth up to around 75mph if you are cruising along and not revving too hard. 

Past 75mph vibrations kick in and quickly lead to discomfort. Despite the vibration-isolating engine mounts, the skinny seat and solid-mounted clip-on bars are not equipped to handle the vibrations from the Harley Davidson V-twin engine

The drive belt unfortunately was known for its tendency to snap. It is a pretty quick and easy fix by swapping the standard Buell belt tensioner out for an aftermarket one that automatically varies the tension. 

It is important to not compare the Firebolt to Japanese counterparts. Doing so will leave you sorely disappointed and you would be doing the bike a dis-service. 

The engine is more than capable of providing a fun, engaging experience on the track but it is best served as a street going sportsbike. 

The lack of top end speed on the track may lead to disappointment and the vibrations can be distracting over a period of time. However, for road use within legal speed restrictions, the Firebolt XB12R is spot on, leaving you wanting for nothing. 

Chassis, Suspension, Handling, Brakes

When it came to the chassis of the XB series Buell didn’t slack in any department. 

The aluminium frame is lightweight and rigid, it is a structure that is not only the backbone of the bike, but it supports the fuel tank. 

By using the frame to carry fuel it lowered the centre of gravity significantly and increased the efficiency of rider input to the bikes reaction. 

One note here is that crash damage to the frame can be more traumatic than other bikes that aren’t doubling up as a fuel tank. A trick owners began to use to avoid the risk of writing their bikes off completely in an accident was to implement frame protectors. 

Be sure to check that these have been fitted properly and are structurally sound without affecting other components. If frame protectors are fitted you want to run a background check to ensure the bike hasn’t received any structural damage prior. 

The muffler is located centrally under the engine further enhancing the low centre of gravity, making for a very well-balanced bike. 

The only issue with the muffler under the engine is that it was prone to rust, being low to the ground, in wet conditions spray would just constantly kick up underneath. 

However, there are many products today that you can use to protect your exhaust from the elements, so giving it a good clean and using a protective spray should keep everything in good condition. 

It wasn’t just the frame that served a dual-purpose; the aluminium swingarm doubled up as an oil reservoir. 

Showa suspension in the form of inverted forks and a mono-shock are completely capable and are fully adjustable to suit the rider and conditions. 

Overall handling of the Buell Firebolt XB12R is impeccable; it is nimble with rapid steering, surprisingly agile and abundantly fun in corners. It also feels very stable and capable of handling the masses of torque the engine pumps out. 

The Showa rear shock feels firm, paired with a fast steering, the bike isn’t necessarily a relaxed ride, but one you have to commit to and give your undivided attention. 

Personally, I love this, a motorcycle that completely captures my focus, demands my full attention. A far cry from HD cruisers that are more about the laid back experience of the journey (which is great but in a different way). 

Ergonomics are distinctly sporty, but not incredibly physically demanding. Clip ons force you to lean forward slightly as well as the pulled back footpegs, but it is definitely more of a sports-tourer riding position than all out Yamaha R1. 

Where the XB series was ahead of the game was with the ZTL front braking system. Essentially this out the brake disc on the outer edge of the wheel instead of at the hub. 

The idea is that the system allows the suspension to work more efficiently, improved control and traction by reducing unsprung weight on the front wheel as only a single disc and caliper are needed as opposed to dual setups on other bikes. 

An aluminium lightweight spoked wheel could also be used as a result, further reducing weight. 

There was some dispute about the pitfalls of the ZTL system with weight being transferred closer to the tire, and a concern over heat transference, with a Suzuki engineer pointing out the design flaws.

However in testing Buell’s Director of analysis, test and engineering processes confirmed that the ZTL had no ill-fated consequences and stood wholeheartedly by the design. As it turns out the ZTL system has stood the test of time and proved doubters wrong. 

In terms of styling nobody will mistake the Buell Firebolt XB12R for anything else as it simply doesn’t look like anything else. It is a contradiction of sorts with premium parts paired with others that seem less expensive. 

The swingarm and frame, magnesium-toned clutch and cam covers, windscreen, wheels, seat cover all look extremely premium. 

Yet the inner fairing panels fail to look finished, the analog instrument panels are easy to read but look a little basic and out of date.

It makes sense that the overall finish of the bike is confusing as fundamentally you have a very old, traditionally based engine merged into a high tech frame, the Firebolt is the coming together of the old and new, so from that perspective the overall finish in my opinion is perfect.

You won’t see many on the streets, and you will find your Buell to be a talking point when you do stop. The Firebolt is a proud American built sportsbike and that alone give it some prestige. 

Buell XB12R Firebolt Specifications

Engine and Transmission Spec’s

  • Engine – 45 degree V-twin, air cooled four-stroke, pushrod actuated overhead valve, hydraulic self-adjusting lifters, 2 valves per cylinder
  • 1203cc
  • Bore x Stroke – 88.9 x 96.8mm
  • Compression Ratio – 10.0:1
  • Air-Cooled
  • Exhaust – 2 into 1 Buell interactive exhaust system
  • Induction – 49mm DDFI II fuel injection
  • Max Power – 103 peak horsepower at 6,800 rpm
  • Max Torque – 114Nm at 6,000 rpm
  • Transmission – 5 Speed
  • Final Drive – Belt

Buell Firebolt by the Numbers

  • Frame – Aluminium frame with Uniplanar powertrain vibration isolation system
  • Rake – 21 degree
  • Trail – 83mm
  • Front Suspension – Showa 41mm inverted forks 
  • Rear Shock – Showa coil-over monoshock
  • Front Brake – ZTL type brake, 6 piston caliper, 375mm single-sided, stainless steel, floating rotor
  • Rear Brakes – Single 240mm disc, 1 piston floating caliper
  • Length – 1924mm
  • Width – 768mm
  • Height – 1092mm
  • Wheelbase – 1320mm
  • Ground Clearance – 127mm
  • Seat Height – 775mm
  • Dry Weight – 179kg
  • Fuel Capacity – 14 litres

Buell XB12R Firebolt Top speed

The Buell Firebolt XB12R is said to have a top speed of 155mph and can perform the standing quarter mile in 11.4 seconds at a speed of 113mph. 

Buell XB12R Firebolt Value

In the UK prices for a Buell XB12R tend to be in the region of £5,000-£7,000.

eBay UK
Buell Firebolts For Sale Buell Firebolts For Sale

Click to see all the current Buell Firebolt motorcycles listed on eBay UK

(opens in a new window)

I may earn a commission if you make a purchase, at no additional cost to you.

There are some exceptions where you may be able to pick up an example a bit cheaper.

This 2006 model has upwards of 30,000 miles on the clock and could do with some tidying up as rust has gotten the best of the exhaust system. 

However, for £3,795 it is a good buy and providing you can do the basics when it comes to maintenance you would have yourself a head turning sportsbike. 

This 2003 example has done just 3,427 miles and is immaculate with some upgraded carbon fibre components, it is priced at £6,995.  

In North America the price is around $4,000 for a good condition Firebolt. 

One great example is on Cycle Trader with an asking price of $4,390, the bike has only covered 1,800 miles so is virtually brand new.  

Another on Motohunt is advertised at $4,200 and is in a striking yellow paint scheme with sub-10,000 miles on it. 

The bikes are easy to work on and are of a very basic build nature, self-servicing shouldn’t be an issue for most riders. 

You may struggle to track down some original parts but there is a healthy aftermarket supply of parts that are up to the job. 

Reliability with the XB range wasn’t really an issue and still isn’t today with current owners, it is rumoured that HD had a bigger input with the XB range to make quality long-lasting motorcycles. 


Buell are confirmed to be back in business as of 2021 under new ownership of EBR (Erik Buell Racing), a full varying line-up of cruisers, tourers, dirt and adventure bikes are expected to be produced over the coming years. 

I think there is a gap in the market for Buell motorcycles and the Firebolt XB12R is a solid example of an alternative kind of street motorcycle; with a good amount of power coming out of a very traditional V-twin Harley engine. 

It will never be as smooth as Japanese inline fours but that isn’t what it is all about. 

Buell produced a sportsbike using a traditional powertrain for cruisers, the latest Harley line-up and rumors suggest that they themselves are moving into a direction to see what they can do beyond the Harley cruiser, one look at the Pan-America proves this.

The Buell Firebolt XB12R was the American made sportsbike that the world had been asking for, for a really long time and actually it was a pretty good one.

Please support by sharing

Mark J. Willingham, 1

Monday 13th of February 2023

I have a 2009 buell xb9sx. Great daily rider

Ellis Martin

Thursday 8th of December 2022

I bought an 07 12 R last year, and have been enjoying the heck out of it. Its got charging issues and at the end of a ride the side stand ( theres no center stand ) fell away as its bolts had sheared. Still, had for years wanted something like this and had'nt been riding for twelve years or so. Plus my only previous machine was a 79 Yamaha SR 500 ! So the 12 R has much more urge than I'd previously handled.