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MotoLibrary Score
39/100Commuter
Power/Weight
0.17 hp/kg
Torque
31 Nm
Engine
350 ccm
Technical Overview
1994 Jawa 638 Technical Analysis & Specification Breakdown
Built around Jawa's motorcycle platform, the 1994 Jawa 638 features a 350 cc (21.4 cu in) twin, two-stroke configuration. In factory specification, peak output is rated at 26 HP (19 kW) at 5,500 rpm while maximum torque reaches 31.4 Nm (23.1 lb-ft) at 4,750 rpm, transferring power to the rear wheel through a 4-speed gearbox. With a specific output of 74.3 HP per liter and a 750 rpm working window between peak torque (4,750 rpm) and peak power (5,500 rpm), the engine character is indicating a tractable, stress-free state of tune focused on everyday usability and broad torque delivery.
On the scales, the 638 measures 155 kg (342 lbs) dry, translating to a power-to-weight ratio of 0.17 HP/kg (5.96 kg per horsepower). Rider ergonomics and chassis geometry center around a 800 mm (31.5 in) seat height — offering a neutral standover height that accommodates most average-inseam riders without sacrificing cornering clearance. The 17-liter (4.5 US gal) fuel tank supports practical everyday commuting and weekend road stints.
Specific Output
74.3 HP/L
Power-to-Weight
0.17 HP/kg (5.96 kg/HP)
Power Band Window
4,750–5,500 rpm
Standover Height
800 mm (31.5 in)
Engine
Displacement350.0 ccm (21.36 cubic inches)
Engine TypeTwin, two-stroke
Engine DetailsTwin, two-stroke
Power26.0 HP (19.0 kW)) @ 5500 RPM
Torque31.4 Nm (3.2 kgf-m or 23.1 ft.lbs) @ 4750 RPM
Transmission
Gearbox4-speed
Wheels & Brakes
Front BrakesExpanding brake
Rear BrakesExpanding brake
Dimensions & Weight
Dry Weight155.0 kg (341.7 pounds)
Power/Weight0.1677 HP/kg
Seat Height800 mm (31.5 inches) If adjustable, lowest setting.
Use this page to compare this motorcycle by its real specifications, not only by model name. Focus on the details that affect fit, comfort, handling, range and ownership.
Power
Compare engine output with similar motorcycles if acceleration, highway use or two-up riding matters.
Torque
Torque is useful for judging real-world pull, especially for touring, commuting and loaded riding.
Seat Height
Check the seat height against your inseam and riding posture before choosing a motorcycle.
Weight
Compare weight carefully because it affects low-speed handling, parking and confidence.
Fuel Capacity
Fuel capacity helps estimate touring range and how often you may need to stop.
Brakes
Brake setup is worth comparing if you ride in traffic, mountains or with a passenger.
Transmission
Transmission and final drive affect maintenance, smoothness and everyday usability.
