Engine family SZEXX.156DB1

What this record says

Sold in the US by

Zuma Extreme Sports Co.,Ltd.

Engine built by

Zhejiang Zuma Moto Co., Ltd.

Vehicle category

Off-Road Motorcycle

Certificate numbers

SZEXX.156DB1-004

What the number itself says

Reading SZEXX.156DB1 left to right: S is the model-year letter for 2025, ZEX is the three-character code the EPA assigned to Zuma Extreme Sports as certificate holder, X marks an off-road certification, .156 is the displacement in litres, so 156cc and DB1 is Zuma Extreme Sports' own sequence for that year. Nothing in the number names the factory — that comes from the certificate itself.

The engine, as described on the certificate

The test vehicle Zuma Extreme Sports submitted for this family (model K3-155) carried engine code ZS1P60YMJ. In the Chinese engine-model convention that reads as one cylinder, horizontal (flat) cylinder, with a nominal 60 mm bore, YMJ series.

The certificate describes a four-stroke, single-cylinder engine with 2 valves per cylinder fed by carburettor. There is a catalytic converter in the exhaust, recorded as "TWC, single bed, open loop".

Rated power on the record is 10 kW (about 13 hp) at 8,500 rpm, driving through a 4-speed manual gearbox.

Engine code on test vehicle

ZS1P60YMJ

Nominal bore (from the code)

60 mm

Cylinders / valves

1 · 2 per cylinder

Cycle

four-stroke

Fuel delivery

carburettor

Oxygen sensor

no

Engine control

other

Catalytic converter

TWC, single bed, open loop

Rated power

10 kW (≈13 hp)

Rated speed

8,500 rpm

Transmission

4-speed manual gearbox

Sales area

50S

Vehicle built by

Zhejiang Zuma Moto Co.,Ltd.

Test vehicle model

K3-155

Filing history and where it was sold

Zuma Extreme Sports filed one certificate under this family, for model year 2025, sold as 50-state, California included.

The vehicle itself is recorded as built by the same company, Zhejiang Zuma Moto Co.,Ltd. in China — engine and chassis from one source.

Certified emission levels: CO 6, HC+NOx 0.4 g/km.

Other records carrying the same engine code

Zuma Extreme Sports certified an engine with this code under 3 other family numbers — the same engine filed again in another year, or in an off-road and a street version:

• PZEXX.156DB1 (2023)
• RZEXX.156DB1 (2024)
• TZEXX.156DB1 (2026)

Other certificate holders whose test vehicle carried the same engine code:

• Tao Motor Inc.TTMMX.140DBA2026 · different engine factory
• Tao Motor Inc.STMMX.140DBA2025 · different engine factory
• Tao Motor Inc.RTMMX.140DBA2024 · different engine factory
• Tao Motor Inc.PTMMX.140DBA2023 · different engine factory
• Tao Motor Inc.NTMMX.140DBA2022 · different engine factory

A shared code from the same factory is a strong search lead. From a different factory it is as often a naming coincidence. Either way it narrows the search; it does not settle it — measure before you buy.

Models certified under SZEXX.156DB1

Every model designation the importer listed on this certificate. If your machine's model name appears here, this is the right record — even if the name on the bodywork is slightly different.

K3-140 · K3-150 · K3-155 · K3R-140 · K3R-150 · K3R-155 · K4-140 · K4-150 · K4-155 · S4-140 · S4-150 · S4-155 · S5-140 · S5-150 · S5-155