Taking a 50cc Scooter on Faster Roads: Speed Gaps, Bridges and Route Choices

On Hanoi’s Nhật Tân Bridge, information from the city’s Department of Construction, reported in September 2026, gives a maximum of 80 km/h in the car lanes and 40 km/h in the motorbike lane, a gap of 40 km/h. This article sets out what Vietnam’s road traffic law, a transport ministry circular, a Yamaha Vietnam explainer and Hanoi bridge reports say about gaps like that one. It is written for a rider planning a route for a slow 50cc scooter on fast roads, and it reports what each page states, with dates, without ruling on any road.

What the law calls a 50cc scooter

Article 34 of Law 36/2024/QH15 on Road Traffic Order and Safety, read on the national legal database vbpl.vn, defines a moped (xe gắn máy) as a two- or three-wheeled motor vehicle with a design speed not above 50 km/h and, for a combustion engine, a displacement not above 50 cm³. Yamaha Motor Vietnam’s explainer (posted 12 August 2025) restates this, although its comparison table marks the moped engine size as below 50 cm3 while its own text says not greater than 50 cm3. The definition names both a design speed and an engine size, and the pages do not say how to check a particular scooter’s design speed; that detail is one to ask the shop.

Maximum speeds side by side

Circular 38/2024/TT-BGTVT (vbpl.vn) sets maximum operating speeds; Article 4 applies the figures below on road sections with no maximum-speed sign. Its Article 7 gives mopeds 40 km/h on every road except an expressway, and its Article 6 gives other motor vehicles, motorcycles included, the figures below. A divided road (đường đôi) has a central divider, and built-up figures apply between the circular’s start and end of built-up area signs.

Subtracting gives gaps between limits: 20 km/h against a motorcycle on a divided road in a built-up area, 10 km/h on a two-way one, and 50 km/h against a car on a divided road outside built-up areas. These are differences between maximums, not measured traffic speeds, and no page reports any. Yamaha’s table lists 70 and 60 km/h for motorcycles under its built-up heading, which disagrees with the circular (60 and 50 there, 70 and 60 outside); the circular is the primary text. Vietnam’s 40 km/h Moped Limit: What the Rule Covers and What It Leaves Open for Day Trips looks at the 40 km/h rule on its own.

Roads a moped cannot use at all

Article 25 of the law lists mopeds and motorcycles among the vehicles that may not travel on an expressway, apart from people and vehicles serving its management and maintenance. Article 9 of the circular sets expressway speeds at 120 km/h maximum and 60 km/h minimum, with the values for a given expressway set in its approved traffic plan. Article 7’s 40 km/h moped maximum is stated for roads other than expressways, so setting it beside that minimum is only an example sum (60 – 40 = 20), not a rule in either text. A VOV report of 26 December 2023, credited to VTC News, described Hanoi’s elevated Ring Road 3 (Vành đai 3 trên cao) as closed completely to motorbikes, quoted Hanoi traffic police saying riders enter despite prohibition signs, and reported car-motorbike collisions on it. The report dates from 2023; Article 11 of the law requires road users to follow road signals, so the signs at an entrance are what apply on the day.

Bridges: how Nhật Tân and Vĩnh Tuy split their lanes

According to information from the Hanoi Department of Construction reported by VietnamPlus on 27 September 2026, a traffic pilot runs on Nhật Tân Bridge from 27 September 2026 to the end of 27 March 2027. Lane 1, beside the central divider, drops from 90 to 80 km/h in both directions; lanes 2 and 3 stay at 80 km/h; lane 4, titled a road for motorbikes and bicycles, stays at 40 km/h. VOV reported the same day that the department’s deputy director described the bridge as carrying heavy traffic at relatively high speed, with some chain collisions in 2026, including those on 7 February and 17 August, and that the distance-marker signs set up for the pilot were temporarily taken down by about 16:00 that day. The department said the plan could be adjusted after monitoring.

An older report shows a different pattern. VOV (31 August 2023) said Vĩnh Tuy Bridge phase 2 has four lanes: three for motor vehicles at up to 60 km/h and one mixed lane for motorbikes and non-motorised vehicles at up to 40 km/h, kept apart by a hard divider. It added that some riders still entered the car lanes out of habit. Phase 1 was described as one-way from Long Biên to Hai Bà Trưng, with four motor-vehicle lanes at up to 40 km/h and a mixed lane at up to 30 km/h.

Rules that apply on any bridge

• Article 12 of the law: speed must suit the bridge, road, traffic density, terrain and weather, and a driver must watch and slow or stop at narrow bridges and culverts, among other places.
• Article 13: a vehicle moving slower keeps to the right, and on a lane reserved for one type or group of vehicles, drivers of other types may not enter it.
• Article 15: no U-turns on a bridge or at a bridgehead, unless a traffic controller or a temporary sign directs it.
• Article 18: no stopping or parking on a bridge unless traffic organisation allows it. Stopping on a Bridge or Flyover With a Fault: Getting Clear of the Carriageway Safely covers a fault on a span.

A route check for a 50cc scooter on fast roads

These points are general planning steps assembled from the statements above, not instructions from any source. Road restrictions and lane arrangements change, so confirm each one on an official page or notice before setting out.

1. Rule out expressways first, since the law bars mopeds from them, and treat a road reported as closed to motorbikes, such as the elevated Ring Road 3, the same way. Hanoi Motorbike Routes in Google Maps: Check Expressways Before Riding covers map routing.
2. For each bridge, look for a recent official notice on its lane layout and read the signs on arrival. Article 10 of the circular lets the road authority set speed signs by direction of a divided road, by time of day and for vehicle types judged high-risk.
3. Compare the posted maximum of your lane with its neighbour’s, as at Nhật Tân.
4. Put turning points and rest stops off the span (Articles 15 and 18).
5. Re-check short-term arrangements: the Nhật Tân pilot is dated to 27 March 2027 and may change before then.

For questions about renting rather than roads, see the Hanoi Motorbike Rental FAQ.

What the pages leave out

• Measured speeds: every figure is a posted or legal maximum, and no page records how fast traffic actually moves.
• Other bridges: nothing read describes Thăng Long, Long Biên, Chương Dương or Thanh Trì for mopeds. VOV (27 September 2026) says some vehicles were restricted on Thăng Long Bridge for a weighing-station project but not which vehicles or for how long.
• Currency: the Vĩnh Tuy and Ring Road 3 reports date from 2023, and nothing says what follows the Nhật Tân pilot after 27 March 2027.
• Expressway-type roads: no page lists which Hanoi roads fall under Article 25; the Ring Road 3 account is a news report, not a traffic order.
• Lower lanes: Vĩnh Tuy phase 1’s mixed lane is reported at 30 km/h, under the circular’s 40 km/h moped maximum, and no page explains how the two figures interact.
• Scooter specifics: no page gives the class or top speed of any rental scooter, and no manufacturer manual for a 50cc model was found; Yamaha’s page is an explainer.
• Penalties are not covered, and nothing here says what any rental shop’s scooters may do on a given road.

Sources checked

• National legal database: Law 36/2024/QH15
• National legal database: Circular 38/2024/TT-BGTVT
• VOV: Vĩnh Tuy Bridge lanes (31 August 2023)
• VietnamPlus: Nhật Tân Bridge pilot (27 September 2026)
• VOV: Nhật Tân distance signs (27 September 2026)
• Yamaha Motor Vietnam: moped and motorcycle (12 August 2025)
• VOV: elevated Ring Road 3 (26 December 2023)

Thuê xe máy Nguyễn Hà is open 09:00–21:00 daily at Ngõ 5 Nguyễn Văn Cừ, Bồ Đề, Long Biên, Hà Nội (near Gia Lâm bus station). Phone: 0334 699 969.