Flagship Comparison: 1998 Triumph Thunderbird

Triumph's lightweight contribution to the flagship comparison

1998 Triumph ThunderbirdFran Kuhn

The original Thunderbird was Triumph’s first “big” bike, a 650 derived from its 500cc vertical twin. Created after World War II for a push into the American market, it was the first British bike that many American enthusiasts ever saw. The 1998 Thunderbird has little in common with that motorcycle other than a few styling elements.

The new bike is powered by a modern, liquid-cooled, dual-overhead-cam, 885cc, in-line vertical triple with three carbs, four valves per cylinder and five speeds. It’s bigger too, with a 62.2-inch wheelbase and a wet weight of more than 500 pounds—which makes it comparatively light in this crowd. Its chain final drive is lighter than the shafts of most of the other bikes, as well. The engine is a stressed component of the frame, which has no cradle tubes.

The three-into-two exhaust system terminates in a pair of mufflers (the right and middle cylinders use the right muffler) similar to those of 1960s-era Triumph twins. Naturally, the triple’s sound is very different than the sound of the old twins. Since the T-Bird’s style evokes classic British rather than classic American styling, its nostalgic touches include a one-piece dual saddle with a passenger grab rail, footpegs instead of floorboards, and the four-gallon tank’s shape, badges and paint scheme. The Bird also uses classic wire-spoked wheels, though these have radial tires—in this case Michelin 89X series, running tubes. Like the late-model twins, the 900 Thunderbird wears a speedo and tach above the headlight.

Its lightweight style makes the T-Bird a standard-style machine rather than a cruiser for some riders. All of Triumph’s Thunderbird models, which include the Adventurer and the more muscular Thunderbird Sport, share the T-Bird’s basic engine and chassis design, and $8995 suggested price.

High Points: Low Points: First Changes:
Responsive handling Not a mainstream cruiser Aftermarket seat
Strong acceleration Mushy front brake Work on front brake
Smooth engine Small for bigger riders
Nice rendition of Brit-bike nostalgia Dumb oil-level check arrangement
Comfortable for small to average riders
Comparatively affordable
Lowest price here
Though it has no actual parts in common with the Triumph motor-cycles of the ’80s and earlier, the Thunderbird successfully connects to the bikes of that era with its styling— including the chrome tank badges.Fran Kuhn
Model/designation: Thunderbird
Suggested base price: $8995
Standard colors: Green/silver, black/red, red/silver, black
Extra cost colors: NA
Standard warranty: 24 mo., unlimited miles
Recommended service interval: 12,000 miles
Engine & Drivetrain
Type: Liquid-cooled, transverse inline triple
Valve arrangement: DOHC, 2 intake, 2 exhaust valves, shim adjusters
Displacement, bore x stroke: 885cc, 76mm x 65mm
Compression ratio: 10.0:1
Carburetion: 3, 36mm Mikuni CV
Lubrication: Wet sump, 4.2 qt.
Minimum fuel grade: 87 octane
Transmission: Wet, multiplate clutch; 5 speeds
Final drive: Chain, 2.529:1
Wet weight: 526 lb
GVWR: 961 lb
Seat height: 29.5 in.
Wheelbase: 62.2 in.
Overall length: 87.1 in.
Rake: 27 degrees
Trail: 4.2 in.
Wheels: Wire-spoke, 18 x 2.50 front, 16 x 3.50 rear
Front tire: 110/80ZR-18 Michelin A89X, tube-type radial
Rear tire: 160/80ZR-16 Michelin M89X, tube-type radial
Front brake: Single-action twin-piston caliper, 12.6-in disc
Rear brake: Single-action twin-piston caliper, 11.2-in disc
Front suspension: 43mm stanchions, 5.9 in. travel
Rear suspension: Single damper, 4.3 in. travel, adjustments for spring preload
Fuel capacity: 4.0 gal (1.0 gal reserve)
Handlebar width: 28.8 in. wide, 7⁄8-in. diameter
Inseam equivalent: 34.4 in.
Electrical & Instrumentation
Charging output: 300 watts
Battery: 12v, 14AH
Forward lighting: 7-in. headlight
Taillight: Two bulbs, license plate light
Instruments: Speedometer, tachometer, odometer, tripmeter, lights for neutral, high beam, left/right turn signals, oil level, coolant temperature
Fuel mileage: 33–43 mpg, 38.1 mpg avg.
Average range: 153 miles
RPM at 60 mph, top-gear: 3900
200 yard, top-gear acceleration from 50 mph, terminal speed: 77.3 mph
1⁄4-mile acceleration: 13.41 sec., 99.2 mph

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