1977 Harley-Davidson MX250 Specifications and Specs

Specifications and workshop reference information for the 1977 Harley-Davidson MX250, including engine, chassis, service data and setup details.

Note: Specs are compiled from factory data, manuals and owner feedback. Bikes vary — if yours is different, jump into the forum and share it.

1977 Harley-Davidson MX250

ENGINE

Engine TypeAir-cooled two-stroke single-cylinder
Displacement242 cc
Compression Ratio11.8:1
Maximum PowerApproximately 32 hp at 9,000 rpm
Carburetor38 mm Dell'Orto | Replacement Options
InductionFive-port cylinder with bridged intake
Cylinder BoreChrome plated
IgnitionCDI, Dansi or Motoplat depending on production fitment
Fuel SystemPremix two-stroke lubrication | Premix Calculator

TRANSMISSION

Transmission5-speed close-ratio
ClutchMulti-plate wet clutch
Primary DriveStraight-cut gears
Final DriveChain

CHASSIS

FrameChrome-moly steel double-downtube frame
Steering Rake30 degrees
Wheelbase58 in (1,473 mm)
Seat Height34.2 in (869 mm)
WeightApproximately 253 lb (115 kg)

SUSPENSION

Front Suspension36 mm Kayaba leading-axle telescopic forks | Fork Oil Levels
Front Wheel Travel9 in (229 mm)
Rear SuspensionTwin Kayaba remote-reservoir shock absorbers | Rear Suspension Setup
Rear Wheel Travel9 in (229 mm)

WHEELS & TYRES

Front Rim21 in Akront aluminium rim
Rear Rim18 in Akront aluminium rim
Front Tyre3.00-21 | Tyre Size Guide
Rear Tyre4.60-18 | Tyre Size Guide
Wheel HubsLeleu

BRAKES

Front BrakeDrum
Rear BrakeDrum

250cc Other Specs

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