Tim McKinney

A Ride Aboard the 1999 Harley-Davidson FXDS Dyna Convertible

Repeat performance from H-D

This article was originally published in the December 1998 issue of Motorcycle Cruiser.

Imagine a cruiser that, with the twist of an allen key and the loosening of two knurled knobs, transforms from vagabond- to boulevard-mode in less than five minutes. Now, for the motivating force, bolt in Harley-Davidson's new, beefy, 88-inch Twin Cam 88 Fathead engine. The first new engine produced by the Motor Company in the 15 years since the Evolution Big Twin spearheaded the company's phenomenal turnaround.

In fact, it was the engine that prompted us to choose the Dyna Convertible. The Convertible was the last Evo-powered Harley we had tested that has subsequently switched to Twin Cam power. So with the old Convertible still fresh in our minds, it seemed to be the ideal way to sample the new engine. The engine was the focus of our ride, but since our planned venue was Main Street Across America, the Convertible also seemed like the perfect choice.

The Convertible’s job description calls for it to act as two bikes while filling only one space in its owner’s garage. Of course, minimal time and effort should be required to convert from one bike to the other. The first bike, the light-duty tourer, would utilize a windshield and easy-to-remove saddlebags. And a bike destined to be pointed at the opposite horizon needs a comfortable seat and a variety of places for the rider to place his feet and unkink his legs.

Harley-Davidson's FXDS Dyna Convertible Engine
Here’s the source of most of the positive comments about the Convertible. See how many changes you can spot. Go ahead, consult our October ’97 test for some ideas.Tim McKinney

Other rider accommodations should be equally flexible. The boulevardier doesn't need extras cluttering things up. Lose the windshield. Bags only block the view of the rear wheel. Staggered shorty duals look right and should make what the mainstream media calls, "The Sound." A 45-degree, single-crankpin V-twin with lots of torque off the line, if you please.

Saturday Night Special

The Convertible in around-town trim carries much of the same hardware as the other sporty members of Harley’s Dyna Glide line. The fork rakes out only 28 degrees for quick steering. The frame consists of a mild steel, rectangular section backbone with twin downtubes. A 19-inch front wheel shod with a 100/90-19 Dunlop Elite and a 16-inch rear wheel clad in a 130/90B-16 Dunlop Elite keep the frame off the ground. A 39mm fork takes care of bump absorption up front while two, five-position preload adjustable dampers do their duty out back. A classic stepped seat props the rider up as a buckhorn handlebar reaches back, to complete the laid-back riding position. Underneath the 4.9-gallon tank, cradled in the frame’s clever rubber mounting system, the Motor Company’s new engine provides the street cred that’s so important when pulling into the local bistro.

Harley-Davidson's FXDS Dyna Convertible Engine
The crankcases offer increased strength with less weight. We fashioned the shifter pad in rural Nebraska out of hardware store items for less than the cost of a cheeseburger platter at a roadside café.Tim McKinney

Furthermore, the Twin Cam 88 engine is exclusive to Harley-Davidson. The Fathead’s design pursued two goals. The first was to refine the existing Big Twin powerplant, with an eye toward eliminating the weak points encountered by hot-rodders building engines with displacement crossing into the 100-inch territory (and possibly Harley’s R&D teams designing future Bigger Twins). The second goal was to launch a frontal assault on the manufacturers who made it possible to build entire engines patterned on the results of H-D’s design investment on the Evolution motor without using a single factory part.

Improving the Big Twin started almost from scratch. Out of the 450 parts incorporated into the Twin Cam 88, only 18 hail from the Evolution. Ten new patents—covering components such as the oil pump and the shape of the cases—protect Harley from a repeat of the cottage industries that sprouted up around the Evo engine. Creative builders in the aftermarket will undoubtedly be able to improve upon the Fathead, but the Motor Company may have ended the days of the complete Harley-patterned engines.

When considering the Twin Cam engine, themes of lightness, strength, and efficiency run through the list of changes. The crankcases benefit from a high-pressure process and arrive on the assembly line stronger, lighter, and manufactured to tighter tolerances. The straight single crankpin sports an increased diameter for more bearing area, increased reliability, and the ability to withstand the higher output of performance-tuned (read: large displacement) engines. Forged flywheels get a tougher press fit introduction to the crank. Beefier knife-and-fork connecting rods guide lighter, wider, 95.3mm pistons through a shortened 101.6mm stroke, yielding both a 1450cc (or 88-inch, as in Twin Cam 88) displacement and a higher 5500-rpm redline. The combustibles receive their jolt from a smaller 12mm spark plug located in the new bathtub-style combustion chamber, with its higher 8.9:1 compression ratio.

Harley-Davidson's FXDS Dyna Convertible
The Convertible can be transformed from a light-duty tourer to a boulevardier.Tim McKinney

Two valves (one intake and one exhaust) of a new design but the same diameters as the Evolution items, still usher the players to and from the field. But each cylinder’s valves, hydraulic adjusters, and pushrods are now prodded by their own chain-driven cam—hence the Twin Cam moniker. (Other benefits of the new chain-driven cams include more precise cam timing and less mechanical noise, thanks to the decrease in lash when compared with the old gear-driven cam.) Cool gases flow from the forward edge of the stylish oval airbox, through a 40mm Keihin carburetor, and to the cylinder via reshaped, more efficient ports. Shorty dual pipes dispose of by-products from the fuel consumption process.

Back inside the bottom end, a higher-volume, crank-driven oil pump scavenges the crankcase’s contents more effectively, preventing Evolution-type oil loading of the crankcase. (Oil tended to build to a point where it interfered with the crank and robbed the engine of power.) Also, oil is now filtered before serving its shift within the engine. Oil jets in the crankcase spray oil onto the piston bottoms to keep the cylinders running at approximately the same temperature. This eliminates the Evo’s quirk of having the rear cylinder run cooler because of oil splash-up from the crank. Cylinder temperature is further minimized by a 50 percent increase in fin area.

Harley-Davidson's FXDS Dyna Convertible
Thanks to this ineffective locking mechanism, the left saddlebag leapt from the Convertible for the second year in a row. Nothing of any value was placed in either bag for the remainder of the trip.Tim McKinney

Power pulses make their way from the crank to the wheel via a belt drive and the same old five-speed transmission carried in a stronger case. The more robust connection between the new transmission case and the crankcase prevents stress-associated distortion from hot-rodding power increases, thereby increasing reliability.

Thumbing the Button

Although the Twin Cam engine still requires full choke when it’s cold, the ’99 Convertible runs without enrichening, with a minimum of pops and snorts after only a block or two. The Fathead is noticeably quieter mechanically. However, the transmission still rewards the rider with a resounding thunk on each gear change. Although clutch effort lessened on last year’s Evolution engine, the Twin Cam’s clutch lever operation can be an arm-pumping experience in stop-and-go traffic.

Otherwise, the new engine works better in every way. Blipping the throttle results in quicker revs—even when comparing a carbureted 88 with an injected Evo. Carburetion feels much crisper. Harley claims a 10–25 percent steamier power delivery, and every tester’s pocket dyno agreed with this assessment. Roll-on power makes back-road passing a shiftless affair. Even with the windshield and bags mounted, the Convertible managed a terminal speed of 73.3 miles per hour at the end of a 200-yard, top-gear roll-on. This was a number only two of the flagships we tested in August ’98 (neither of them V-twins) could better without the drag of a windshield. The engine makes enough power to easily carry the bike to triple digit speeds, where ordinary road irregularities begin to unsettle the chassis. The rubber engine mounts ensure vibration never intrudes into the crystal-clear mirrors, even at elevated speeds.

Harley-Davidson's FXDS Dyna Convertible Seat
While some testers didn’t hate the seat, some did. Nobody loved it. Some riders felt cramped by the seat back position and the pulled-back bar. The pillion can only handle the most petite on tour.Dean Groover

The suspension offers a plush, softly sprung ride around town and on the highway. However, the front dives heavily under braking. The narrow front tire interacts with road surface features, hunting for a path instead of tracking on line. Occasionally, the wandering front end conspires with the soft suspension to feed road irregularities back into the chassis in sweepers—particularly rain grooves on ramps connecting two highways—resulting in an unsettling wobble. The Convertible never responds precisely to steering inputs. The rider feels as if the bike is being pointed in a general direction, rather than positively piloted. Factor in excessive compression damping in the rear, which can upset the chassis midcorner, and rider confidence erodes. And square-edged bumps encountered in straight-up mode upset the rider’s pain sensors rather than the bike’s composure.

Harley-Davidson's FXDS Dyna Convertible windshield
We’ve said before that the overly tall windshield would obscure some rider’s vision in inclement weather. Add rain, darkness, and oncoming headlights, and the results could be tragic.Dean Groover

Long Distance Runaround

Ironically, in the touring arena the Convertible was presumably designed for, the bike suffers from several flaws. First, the windshield rises so high that only taller riders can see directly over the Lexan. Riders in the 5’11” to 6’0” range must endure the edge of the windshield (and its associated distortion) crossing directly through their line of sight. Shorter riders are forced to look through the windscreen and any bugs or other flotsam it has collected. One tester struggled to see for 100 miles in a downpour, at night, on a two-lane road, in open range (cows, horses, deer or coyotes potentially congregating on the pavement), with occasional clumps of brightly lit oncoming traffic. A trip to the local plastic shop is in order. Since Harley doesn’t include a tool kit, those who want to take advantage of the windscreen’s easy removability have to provide their own allen key. The windshield does, how­ever, effectively block most wind blasts.

The uniquely styled leather and Cordura saddlebags appear to offer a secure—although not waterproof—means to carry belongings. However, the screw fastener can vibrate loose. For the second year in a row, we had a left-side saddlebag leap from the bike onto the mean streets of Manhattan. Fortunately, neither the bag nor its contents were lost—this time. Since our last test, we’ve heard of other Convertible riders who’ve suffered from spontaneous bag loss. We have to wonder why Harley hasn’t upgraded the fasteners. Also, one of the snaps that holds the front flap in position at speed pulled out of the bag’s seam, allowing the flap to, well…flap annoyingly at speed. The other minor problems we had with the bike in our 6000 miles onboard were a loose wire in the headlight (which made the high beam intermittent), a shift-lever pad which departed in Nebraska, and the nut for the ignition lock, which loosened up.

Harley-Davidson's FXDS Dyna Convertible action
The suspension offers a plush, softly sprung ride arounds town and on the highway.Tim McKinney

The rider’s interface with the motor­cycle is less than ideal. The seat’s crowned center was reviled by some and tolerated by others, while the seat back cramped some riders in relation to the buckhorn bar. The bar was universally condemned. The grips point almost straight down while the levers angle outward, requiring riders to cant their wrists awkwardly to cover the brake or operate the clutch. One rider commented the bar felt like it belonged on a video game, not a motorcycle. The Convertible offers solo riders three footpeg locations (the highway pegs, the standard pegs, and the passenger pegs), “none of which were in the right position,” according to one tester.

The final indignation foisted on us by the Convertible was the overly long sidestand. It required the bike to be leaned to the right to extend the stand—a tricky chore with a full load of gear.

When we tested the Dyna Glide Convertible in our October ’97 issue, we said the bike suffered from a flawed implementation of a good idea. After logging more than 6000 miles in 10 days of intensive, cross-country testing of the 1999 Convertible, we are forced to arrive at the same conclusion, with one notable exception: the Twin Cam 88 engine. Were it not for the new-generation engine, the difference between the old Convertible and the current model could be described as merely new colors. The engine, how­ever, is good enough to improve our testers’ overall impressions of the bike when compared with last year. Although our criticisms about the Convertible could be addressed with some well-placed modifications and a trip to the aftermarket, a bike that retails for more than $14,000 shouldn’t need $500–1000 worth of work to bring it up to speed.

The Fathead engine illustrates what levels of refinement Harley-Davidson can achieve when it so chooses. If the Convertible is to live up to the potential of the idea that spawned it, how­ever, Harley will need to direct the same attention to the chassis as it did to the engine. Then the Motor Company will show why it is an industry leader.

Riding Positions:

The last time stock Harley engines could be considered anything close to potent was back in the late 1960s, before the first generation of superbikes arrived to lay waste to the Sportster. In ’83, when the Evo was introduced, Harley engines went from pig-poor to somewhere in between the acceptable-to-mediocre range—depending on which bike they were in and what equipment they had bolted to them. The Fathead puts Harley at the front of the growing pack of big-inch cruiser V-twins, at least for now. Other manufacturers are hard at work on new bikes and engines, and I expect to see more new, big V-twins before the season is through. But I don’t expect any big twin to just blow this engine away.

When I heard this new Harley engine still had pushrods, cooling fins and one carburetor, I wondered why Harley bothered. But my first ride explained a lot, and riding it across the country next to the Victory made me a believer. The Victory’s engine has more displacement, overhead cams, fuel injection and oil cooling, and the Harley walked away from it, carbureted as well, got better mileage, and (thanks in part to rubber mounts) vibrated less.

The other interesting thing to note about the new engine is the prices that are attached to the bikes wearing it. The base model Harley Dyna has a suggested price that is almost two grand less than the Victory. That’s manufacturing efficiency talking.

And you know Harley isn’t done yet. There will be bigger, fatter Fatheads. And if the same thorough improvement process is applied to the rest of the bike that was devoted to the engine, you may hear words like “passing power,” “performance,” and “reliability” as frequently as you hear “heritage,” “class,” and “nostalgia,” mentioned when people talk about Harleys. —Art Friedman ✰✰✰✰

I’m not a fan of green eggs and ham, and so I’ve said. I’ve tried them here, I’ve tried them there, I’ve tried them everywhere. But when Uncle Sam I Am sent me out of the Milwaukee kitchen riding their new recipe, I immediately thought, “Hmmm, this is different—undeniably a better dish.” Now if they would just rewrite the cookbook on the remaining components… —Jamie Elvidge ✰✰✰✰

Harley hit the ball out of the park with this first iteration of the Twin Cam 88. The engine is smoother, more powerful, better-sounding, and slicker-looking, while still maintaining that distinctive Harley profile. Also consider the fact that the factory has EPA-legal, hop-up kits ready to ship as the first Fatheads are rolling out the door! I can’t wait to test one of the 95-inchers.

The funny thing is, as much as I love the Convertible’s engine, I don’t like the bike. All the little problems that were mildly bothersome last year were incredibly annoying this time around. Maintaining status quo with the faulty saddlebag-mounting system is an insult to the buyer. Being forced to use Loctite or a pair of pliers to make sure the bags don’t remove themselves defeats the purpose of the Convertible. What about designing a bike with an easily removable windshield and then failing to include the tool to remove the windshield? Don’t get me started on the handlebar….

So, why is my star rating higher than last year? The engine. Otherwise I’d have rated the Convertible a full point lower. Right now all I can think about is how cool the 95-inch version of this engine would be, just put it in a different bike—like maybe the fuel-injected Road King Classic. —Evans Brasfield ✰✰✰✰

High Points: Low Points: First Changes:
Awesome engine Tall windshield obscures your view of the road Trim windshield to a safe height
Windshield and bags are easily removed Bags unmount themselves at speed Shorten sidestand to a more manageable length
Great range Bike must be leaned to the right to set sidestand Find a better way to secure bags
Did we say we liked the engine? Uncomfortable handlebar bend Replace handlebar
Designation: FXDS-CONV
Suggested base price: $14,580 ($14,865 in CA)
Standard colors: Black
Extra cost colors: Red pearl, blue pearl, orange pearl, diamond ice pearl—add $240; red/black, blue/diamond ice, orange/diamond ice—add $585
Standard warranty: 12 mo., unlimited miles
Recommended service interval: 5000 miles
Engine & Drivetrain
Type: Air-cooled, 45-degree, tandem V-twin
Valve arrangement: OHV, 1 intake, 1 ex­haust valve, operated by hydraulic adjusters
Displacement, bore x stroke: 1450cc, 95.3 x 101.6mm
Compression ratio: 8.9:1
Carburetion: 1, 40mm Keihin CV
Lubrication: Dry sump, 3.0 qt
Minimum fuel grade: 92 octane
Transmission: Wet, multiplate clutch; 5 speeds
Final drive: Belt, 70/32
Wheels: Cast-aluminum (wire-spoke option, add $320), 19 x 2.5 in. front, 16 x 3.0 in. rear
Front tire: 100/90-19 Dunlop Elite S/T D401
Rear tire: 130/90B-16 Dunlop Elite S/T D401
Front brake: 2, single-action, single- piston calipers, 11.5-in. discs
Rear brake: Single-action, single-piston caliper, 11.5-in. disc
Front suspension: 39mm stanchions, 6.89 in. travel
Rear suspension: 2 dampers, 4.77 in. travel, adjustable for preload
Fuel capacity: 4.9 gal, (0.5 gal reserve)
Handlebar width: 25.5 in., 1-in. diameter
Inseam equivalent: 33.9 in.
Electrical & Instrumentation
Charging output: 360 watts
Battery: Sealed 12v, 18 AH
Forward lighting: 55/60-watt headlight, position lights
Taillight: One bulb
Instruments: Speedometer, LCD odometer/tripmeter; tachometer; fuel gauge; warning lights for high beam, turn signals, neutral, oil pressure
Fuel mileage: 39–47 mpg, 43 mpg avg.
Average range: 210 miles
RPM at 60 mph, top-gear: 2500
200 yard, top-gear acceleration from 50 mph, terminal speed: 73.3 mph
Quarter-mile acceleration: 13.82 sec., 92.8 mph