When old Arnie jumped his “borrowed” Fat Boy into the drainage sluice in Terminator 2back in ’91, he cemented the Fat Boy’s place in American pop culture for all time. Harley has stayed true to the original look, and they’ve continually refined the Fat Boy in the interim to bring us the newest range of models built on the FLSTF platform.

We have the traditional-looking Fat Boy as a base model with the blackout Fat Boy Lo as sort of a side-grade model. The factory included the Fat Boy in its “S-series” program that sees existing bikes souped up with Harley’s biggest production engines and decked out with Screamin’ Eagle performance parts. Join me while I take a look at the specific upgrades H-D sprinkled across the range.

Continue reading for my review of the Harley-Davidson Fat Boy, Fat Boy Lo and Fat Boy S.

  • 2015 - 2017 Harley-Davidson Fat Boy / Fat Boy Lo / Fat Boy S
  • Year:
    2015- 2017
  • Make:
  • Model:
  • Model:
  • Engine:
    Air-cooled, Twin Cam 103B
  • Displacement:
    103 cubic inches
  • Top Speed:
    110 mph (Est.)
  • Price:
    16899
  • Price:

Design

2015 - 2017 Harley-Davidson Fat Boy / Fat Boy Lo / Fat Boy S
- image 677028

(Fat Boy S)

Low and wide have always been the hallmarks of the Fat Boy line, and the newest additions to the family take it down even further. Unladen seat height on the base Fat Boy drops from 27.2 inches to 26.4 inches, while the Lo drops from 26.4 inches on down to an even 26 inches between the ’15 and ’16 models, respectively, though the Lo wasn’t carried forward to 2017. The “S” starts out life already slammed down to 26 inches with only 4.7 inches of ground clearance, right on par with the Lo.

One of the contributing factors that gives the Fat Boy line its distinctive look is the solid rims that adds a visual weight down low. Unfortunately, the solid rims bring with them a significant amount of windage that has an averse effect on tracking in a crosswind and when passing through the pressure waves generated by the passage of other vehicles.

The base model comes with mirror-chrome aluminum wheels, but the Lo and “S” sport matte black hubs in polished aluminum rims for a bit of contrast. While the base model carries chrome in all the usual places, the Lo dips a toe into blackout country with the headlight can, fork skirt, exhaust headers, oil bag and air cleaner cover all getting the treatment. In keeping with its extreme nature, the “S” takes it all the way with blackout front fork sliders, engine covers, mufflers and heat shields for a truly sinister-looking ride.

For 2017, folks in the northern climates will appreciate the addition of the battery-tender harness on the Fat Boy and Fat Boy S as standard equipment.

Chassis

2015 - 2017 Harley-Davidson Fat Boy / Fat Boy Lo / Fat Boy S
- image 676962

(Fat Boy)

Mild-steel tubing makes up the dual-downtube, double-cradle frame with a rectangular, stamped-and-welded backbone. The lines of the frame are laid out to flow from the steering head all the way to the tip of the triangular swingarm in a straight line, just like the rigid frames of old. The result is an old-fashioned look without that old-fashioned feel, hence the “Softail” moniker.

A pair of shocks hidden beneath the transmission handles the suspension and provides 4.4 inches of travel on the base model, and 3.4 inches of travel on the Lo and “S.” The front suspension is consistent across the board with 5.1 inches of travel from 41.3 mm diameter forks, and Harley’s “beer can” shrouds that make them seem a bit fatter than they actually are.

Steering geometry also varies slightly between the siblings with the Lo and “S” running 31.6 degrees of rake to drop them down a skosh lower than the even 31 degrees on the base model, but trail remains the same at 5.1-inches long across the board. As you can imagine, the changes in the rear suspension affects cornering performance. The taller base model allows for 27 degrees of lean to the left, and 26.2 degrees to the right. Slamming the rear suspension on the “S” and the Lo reduced those angles down to 25.2 inches and 25.6 inches, respectively.

Brakes are likewise the same, and all three models come with a single, 300 mm disc and four-pot caliper up front, and a 292 mm disc and twin-pot caliper in back. ABS comes as standard equipment on all Fat Boy models. The 17-inch rims come with a fat, 140 mm hoop up front and an even fatter, 200 mm wide hoop in back, both from Dunlop.

Drivetrain

2015 - 2017 Harley-Davidson Fat Boy / Fat Boy Lo / Fat Boy S Exterior
- image 572181

Harley blessed the Fat Boy and Fat Boy Lo with an upgraded engine package this year. While the ’15 models came with the Air-Cooled, Twin Cam 103B mill, the ’16 models run the high-output version of same. Naturally, these engines show their pedigree in stereotypical Harley fashion with a 45-degree “V” configuration and external pushrods to actuate the two-valve heads. The bores measure out at 3.87 inches with a 4.37-inch stroke for a total displacement of 1,689 cc, same as the previous version, but it cranks out 102.5 pounds of grunt at three grand while the old motor produced 97.4 pounds. Not a huge improvement, but an improvement all the same.

Once again, the “S” ramps up the pressure a few notches. This slammed, blacked-out cruiser runs H-D’s Screamin’ Eagle Air-Cooled Twin Cam 110B. Harley’s biggest engine, the 110B runs a 4-inch bore and 4.37-inch stroke, for an almost-square motor with a total displacement of 1,802 cc. Instead of the round air cleaner like the 103B, the 110B breathes through an oval, low-resistance Screamin’ Eagle filter with an exposed element for a racy, custom look to go along with the extra performance. It also comes with a removable rain sock for you non-fairweather riders out there.

The 110B drives the Fat Boy S well into power-cruiser territory with a total of 108 pound-feet of torque at four grand, making it the largest and most powerful production H-D motor to date. Engine vibration has always been an issue with H-D engines, but the factory took steps to address that with the addition of a counterbalancer to offset some of the shaking from all that reciprocating mass and off-balance firing order.

Both motors come with an electronic throttle feature that allows for a plug-and-play cruise control accessory, which is nifty and progressive as far as it goes, but it can’t yet hold a candle to the rest of the world that is into 2nd and even 3rd generation ride-by-wire, rider modes and traction control. One hopes the electronic throttle is the first step in that direction, and that Harley catches up on the electronic gadgetry sooner rather than later.

All three rides come with Harley’s six-speed Cruise Drive transmission that allows for cruising at highway speeds at a reasonable rpm so you can get where you are going at a less-than-frenetic engine tempo. A quiet and low-maintenance, belt-and-pulley system completes the drivetrain for the Fat Boy line.

Pricing

2015 - 2017 Harley-Davidson Fat Boy / Fat Boy Lo / Fat Boy S Exterior
- image 572177

At the bottom of the range, the base-model 2017 Fat Boy comes with a $16,899 MSRP in Vivid Black, just $200 more than last year.

The 2016 Lo can be had for $17,499, also in Vivid Black, and the optional colors will set you back another four bills, though the Fat Boy Lo is not in the 2017 lineup.

The “S” model rolls for $20,199 in Vivid Black and $20,599 for the Black Denim in a matte finish, an increase of $500 over 2016. It comes with ABS and cruise control as part of the standard equipment package.

Competitors

2016 - 2018 Suzuki Boulevard C90 B.O.S.S.
- image 763408
2015 - 2017 Harley-Davidson Fat Boy / Fat Boy Lo / Fat Boy S
- image 649775

They say imitation is the sincerest form of flattery, and while there are a number of big, V-twin cruisers available on the market, none of them flatter Harley quite as much as the

Boulevard C90 Blacked-Out Special Suzuki (B.O.S.S.)

does a more thorough job with the blackout though, adding the lower fork sliders, engine cases/covers, instrument panel and mufflers to the list of blackened parts over and above that on the Lo. In fact, the overall paint/chrome/blackout scheme looks better on the C90, says I.

The bits of chrome interspersed amongst the black parts on the Lo make it look almost like someone forgot to finish the job, and since the bikes are so similar in shape, the Suzuki comes off looking like the better planned out and more complete product. The downside on the paint, though, is that the C90 comes only in Suzuki’s Metallic Fox Orange. While this isn’t a bad-looking color, and I admit I like orange to start with, it isn’t quite as fetching as Harley’s Amber Whiskey, and naturally the King of Paint offers a handful of additional colors to choose from, for a price.

Honestly, the suspension on both bikes is rather unremarkable. Neither offer any sort of damping or rebound adjustment, and I gotta say that’s a little short-sighted, given how many bikes now sport a variety of ride adjustments that help keep you dialed in to the conditions and passenger/cargo load, never mind how many bikes also offer dynamic, auto-adjusting systems and push-button adjustments that can be made on the fly. In this, Harley and Suzuki could both stand to raise their game just a little bit. Brakes are also a bit of a yawn with little to say about them either, except the Fat Boy at least comes with ABS as standard equipment, while the C90 doesn’t even offer it as an available option.

Now for the powerplants. The 103B in the Lo measures out at 1,689 cc for a slight size advantage over the 1,462 cc, C90 engine. Both run in a V-twin configuration; Harley in its typical 45-degree layout, and Suzuki with a slightly wider, 54-degree V. There are no shortage of 60-plus-degree V-twins out there, but the geometry just doesn’t look right to someone used to Harley engines, and it affects the overall look of the bike. Suzuki gets credit for closing the angle just a little bit for a more natural-looking engine to Western eyes.

Given the difference in displacement, it’s no surprise that the H-D Twin Cam edges out the Suzuki mill at the dyno. The C90 produces 84.8 pound-feet at a low 2,800 rpm, and to be fair, that’s a decent amount of torque that comes on very early. Still, the 103B takes the cake with 102.5 pounds of grunt at three grand.

Pricing is where Suzuki picks up its biggest win. The C90 B.O.S.S. can be had for only $12,399, miles shy of the lofty $17,699 sticker on the Fat Boy Lo. For many, especially new buyers with no brand loyalty that are looking for a certain look, but not necessarily a certain name, this price difference will likely be the deciding factor.

He Said

“Yeah, I’ve always liked the “Fatty” quite a bit, and I am pleased that Harley tapped it as one of the models to get the “S” treatment. For too long Harley has been sort of the “take it or leave it” company, with little in the way of choices in engine, but they finally seem to be responding to demand for more performance. Of course, I feel a sense of irony in cruiser riders looking for more performance, given that style of riding; but hey, I wish I had more power, too. Not sure what all I would do with said power, but I do wish I had it all the same. As for the bikes themselves, they look just about like they always have, which is as it should be.”

She Said

My wife and fellow motorcycle writer, Allyn Hinton, says, “The Fat Boy may not be the best of any one thing in particular, but it’s a nice ride, well balanced and rather is the epitome of the classic American cruiser. It’s a big, heavy bike, acceleration is smooth and responsive and it’s really easy to get along with. If I have any negative to say about it, I’d say that the floorboards scrape a little too easily. I’d like to see a little more lean.”

Specifications

Model: Fat Boy Fat Boy Lo Fat Boy S
Engine:
Engine: Air-Cooled, High Output Twin Cam 103B™ Air-Cooled, High Output Twin Cam 103B™ Screamin’ Eagle® Air-cooled, Twin Cam 110B™
Bore: 3.87 in. 3.87 in. 4 in.
Stroke: 4.374 in. 4.374 in. 4.374 in.
Displacement: 103.1 cu in 103.1 cu in 110 cu in
Compression Ratio: 9.6:1 9.6:1 9.5:1
Fuel System: Electronic Sequential Port Fuel Injection (ESPFI) Electronic Sequential Port Fuel Injection (ESPFI) Electronic Sequential Port Fuel Injection (ESPFI)
Drivetrain:
Primary Drive: Chain, 34/46 ratio Chain, 34/46 ratio Chain, 34/46 ratio
Gear Ratios (overall) 1st: 9.311 9.311 9.311
Gear Ratios (overall) 2nd: 6.454 6.454 6.454
Gear Ratios (overall) 3rd: 4.793 4.793 4.793
Gear Ratios (overall) 4th: 3.882 3.882 3.882
Gear Ratios (overall) 5th: 3.307 3.307 3.307
Gear Ratios (overall) 6th: 2.79 2.79 2.79
Performance:
Fuel Economy: Combined City/Hwy: 42 mpg 42 mpg 43 mpg
Engine Torque (rpm): 3,000 3,000 4,000
Engine Torque: 102.5 ft-lb 100.3 ft-lb 108 ft-lb
Lean Angle, Right (deg.): 26.2 25.6 25.6
Lean Angle, Left (deg.): 27 25.2 25.2
Engine Torque Testing Method: J1349 J1349 J1349
Chassis:
Exhaust: Chrome, over/under shotgun exhaust with dual mufflers Denim Black and Satin Chrome, over/under shotgun exhaust with dual mufflers Black over/under shotgun exhaust with slash-cut mufflers
Wheels, Optional Style Type: N/A N/A N/A
Wheels, Front Type: Mirror Chrome Aluminum Bullet Hole Disc Black, Bullet Hole Disc Cast Aluminum Black, Bullet Hole Disc Cast Aluminum
Wheels, Rear Type: Mirror Chrome Aluminum Bullet Hole Disc Black, Bullet Hole Disc Cast Aluminum Black, Bullet Hole Disc Cast Aluminum
Brakes, Caliper Type: 4-piston front and 2-piston rear 4-piston front and 2-piston rear 4-piston front and 2-piston rear
Parking Brake: N/A N/A N/A
Dimensions:
Length: 93.9 in. 94.1 in. 94.1 in.
Seat Height, Laden: 25 in. 24.3 in. 24.3 in.
Seat Height, Unladen: 26.4 in. 26 in. 26 in.
Ground Clearance: 5.1 in. 4.7 in. 4.7 in.
Rake (steering head) (deg): 31 31.6 31.6
Trail: 5.8 in. 5.8 in. 5.8 in.
Wheelbase: 64.4 in. 64.2 in. 64.2 in.
Tires, Front Specification: 140/75R17 67V 140/75R17 67V 140/75R17 67V
Tires, Rear Specification: 200/55R17 78V 200/55R17 78V 200/55R17 78V
Fuel Capacity: 5 gal. 5 gal. 5 gal.
Oil Capacity (w/filter): 3.5 qt. 3.5 qt. 3.5 qt.
Weight, As Shipped: 700 lb. 704 lb. 709 lb.
Weight, In Running Order: 730 lb. 733 lb. 739 lb.
Luggage Capacity -Volume: N/A N/A N/A
Luggage Capacity -Weight: N/A N/A N/A
Electric:
Lights (as per country regulation), Indicator Lamps: High beam, neutral, low oil pressure, turn signals, engine diagnostics, security system (optional), 6-speed, low fuel warnings, low battery, ABS High beam, neutral, low oil pressure, turn signals, engine diagnostics, security system (optional), 6-speed, low fuel warnings High beam, neutral, low oil pressure, turn signals, engine diagnostics, security system (optional), 6-speed, low fuel warning, low battery, ABS
Gauges: Tank-mounted electronic speedometer with odometer, time-of-day clock on odometer, dual tripmeter, RPM/gear display, fuel gauge with low fuel warning light and countdown feature, low oil pressure indicator light, engine diagnostics readout, LED indicator lights, 6-speed indicator light Tank-mounted electronic speedometer with odometer, time-of-day clock on odometer, dual tripmeter, RPM/gear display, fuel gauge with low fuel warning light and countdown feature, low oil pressure indicator light, engine diagnostics readout, LED indicator lights, 6-speed indicator light Tank-mounted electronic speedometer with odometer, time-of-day clock on odometer, dual tripmeter, RPM/gear display, fuel gauge with low fuel warning light and countdown feature, low oil pressure indicator light, engine diagnostics readout, LED indicator lights, 6-speed indicator light
Color: Vivid Black, Velocity Red Sunglo, Olive Gold, NEW Superior Blue/Billet Silver, NEW Black Hills Gold/Black Quartz - Vivid Black, Black Denim
Pricing:
Vivid Black: $16,899 - $20,199
Color Option: $17,299 - $20,599
Two-Tone Option: $17,649 - N/A
ABS: Standard - Standard
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