How fast is the 1981 Honda C70 Passport?

In stock condition on level ground, a well-tuned 1981 Honda C70 Passport typically tops out at about 45–50 mph (72–80 km/h). Many owners report a GPS-verified maximum of around 45–47 mph, while the factory speedometer can read optimistically into the low-50s, especially with a tailwind or downhill.

What those numbers mean for everyday riding

The C70 Passport is the U.S. market version of Honda’s 72 cc Super Cub: a lightweight, air‑cooled, four-stroke single with a 3‑speed semi-automatic gearbox and chain drive. With roughly six horsepower, it’s engineered for urban and suburban speeds rather than highway cruising. That power, paired with its low weight and streamlined leg shields, allows it to reach the mid-to-high 40s mph in realistic conditions, enough for city arterials and 35–45 mph zones.

Official vs. real-world top speed

Honda did not widely publish a single official top-speed figure for the Passport, and period brochures emphasized economy and reliability over outright speed. Contemporary road tests and owner measurements converge on a real-world maximum of mid-40s mph on flat ground with an average-weight rider. On slight descents or with a favorable wind, indicated speeds can exceed 50 mph; in headwinds, on inclines, at higher elevations, or with heavier riders, expect lows in the 40–44 mph range.

What affects the C70’s top speed

Multiple variables can shift the Passport’s top speed by several mph. Understanding these helps explain why riders report slightly different numbers.

• Rider weight and posture: A lighter rider and a tucked position reduce drag and load, adding a few mph.
• Wind and grade: Headwinds and hills dramatically cut top speed; tailwinds and slight downhills boost it.
• Altitude and temperature: Thinner air at altitude reduces engine power; very hot days can do the same.
• Tire condition and pressure: Underinflated or oversized tires increase rolling resistance and reduce speed.
• Engine tune: Valve clearances, ignition timing/points condition (on 6V models), and a clean carburetor/air filter are critical.
• Drive chain and sprockets: Worn chains or misadjusted slack waste power; non-stock gearing alters both acceleration and top speed.
• Fuel quality and age: Fresh fuel helps maintain consistent combustion; stale fuel can sap performance.
• Speedometer error: Original speedos often read 5–10% high at the top end; GPS gives truer numbers.

Taken together, these factors often explain a spread of roughly 5 mph between different C70s—or the same bike on different days.

How to measure your C70’s true top speed

To get a reliable number, it’s best to verify with modern tools and repeatable methods rather than relying solely on the original speedometer.

1. Use a GPS device or smartphone app and mount it securely where you can read it safely.
2. Warm the engine fully and set tire pressures to spec before testing.
3. Choose a long, flat, low-traffic road; avoid drafting and strong winds.
4. Make several full-throttle runs in opposite directions and average the peak speeds to cancel wind/grade effects.
5. Wear proper gear and obey local laws; consider having a spotter or riding during off-peak times.

Following this approach will give you a top-speed figure accurate to within about 1 mph, accounting for environmental variables.

Getting the most from a stock 1981 C70 (no engine mods)

Before considering any modifications, routine maintenance and small setup tweaks can recover lost performance and help you reach the upper end of the expected top-speed range.

• Perform a tune-up: set valve clearances, check and adjust ignition timing/points (on 6V points models), and ensure a strong spark plug.
• Clean and adjust the carburetor: verify float height, idle mixture, and that the air filter is clean and correctly oiled (if applicable).
• Change engine oil regularly with the correct grade (often 10W-30 per the manual) to reduce friction.
• Service the final drive: correct chain slack and lubrication; inspect sprockets for hooked teeth.
• Set tire pressures to factory spec and ensure wheels spin freely with no brake drag.
• Adopt an aerodynamic posture at speed—sit upright at low speeds, tuck slightly for top-speed runs.

These steps won’t turn the C70 into a highway bike, but they commonly recover a few mph and make top-end cruising smoother and more consistent.

How it compares with other Honda Cubs

Within the Super Cub family, the C70 sits between the C50/Passport 50 and the C90 in both power and speed. Expect a modest gap across models under similar conditions.

• Honda C50/Passport 50 (49 cc): typically 37–43 mph (60–70 km/h).
• Honda C70/Passport 70 (72 cc): typically 45–50 mph (72–80 km/h).
• Honda C90 (85–89 cc): typically 50–55 mph (80–88 km/h).

This hierarchy reflects incremental gains in displacement and torque, with the C70 offering a useful bump over the 50 while remaining lightweight and economical.

Summary

The 1981 Honda C70 Passport is generally good for about 45–50 mph (72–80 km/h) in stock, healthy condition, with GPS-verified results often landing around 45–47 mph on level ground. Variations in rider, terrain, weather, and maintenance explain the rest. Keep it well tuned, maintain proper tire pressure and chain adjustment, and you’ll see the best the classic 72 cc four-stroke can deliver for everyday roads.

What is the top speed of the Honda Passport?

The Honda Passport’s top speed is limited to approximately 110-112 mph, though specific models and years may have slight variations. For example, the 2023 model has a reported top speed of around 130 mph, while newer models, like the 2025, have a governed top speed of 110 mph. 
Here’s a breakdown of top speeds by model year: 

• 2025 Honda Passport: 110 mph
• 2024 Honda Passport: 111 mph
• 2023 Honda Passport: 130 mph
• 2019 Honda Passport: 112 mph

What’s the top speed of a Honda 70?

The Honda 70 had a rectangular speedometer with gear range markings and a maximum calibration of 60 mph (97 km/h). The claimed top speed was 58 mph (93 km/h).

How fast is the 1981 Honda Passport?

This Honda c70 is the perfect motorcycle for either a beginner with its Semi-Automatic shifting or a seasoned rider looking for a fun nostalgic bike to cruise around town on with an estimated maximum speed of 50mph.

How fast does a Honda C70 go?

Specifications

	C100	C70
Engine	49 cc (3.0 cu in) OHV air-cooled single	71.8 cc (4.38 cu in)
Bore x stroke	40 mm × 39 mm (1.6 in × 1.5 in)	47 mm × 41.4 mm (1.85 in × 1.63 in)
Compression	8.5:1	8.8:1*
Top speed	69 km/h (43 mph)