| Component | Specification |
|---|---|
| Engine Code | NF11A (eSP+) |
| Engine Oil | SAE 10W-30 JASO MB (1.3 L) |
| Spark Plug | NGK LMAR8A-9 |
| Battery | YTZ10S |
| Front Tire | 110/70-16 M/C 52S (2.0 bar) |
| Rear Tire | 130/70-16 M/C 61S (2.25 bar) |
The Honda SH series has defined European urban mobility for decades, but the NF11A generation represents a significant engineering milestone. Unlike its predecessors, the SH 350 I utilizes an enhanced Smart Power+ (eSP+) engine, which incorporates a hydraulic cam chain tensioner and an internal oil jet for piston cooling—technologies typically reserved for high-performance motorcycles—to achieve EURO 5 compliance without sacrificing its legendary 16-inch wheel stability.
Engineering Excellence: The eSP+ Powertrain
The heart of the NF11A is its 330cc liquid-cooled SOHC engine. By increasing displacement from the old 300cc unit, Honda engineers optimized the intake and exhaust efficiency. The use of a 10% lighter crankshaft and larger throttle bodies (36mm) ensures that the SH 350 I delivers linear torque across the rev range, making it the most capable ‘high-wheel’ scooter for both city filtering and motorway commuting.
Maintenance Guide: Keeping the NF11A in Peak Condition
Lubrication System
The NF11A is sensitive to oil friction. It specifically requires SAE 10W-30 JASO MB oil. The ‘MB’ rating is critical; because the SH 350 I uses a dry centrifugal clutch and a CVT transmission, it does not require the friction modifiers found in ‘MA’ oils used for wet clutches. Using the wrong oil can lead to decreased fuel efficiency and increased internal wear. Total capacity is 1.3 liters during a standard change.
Ignition and Electrical
For optimal combustion under EURO 5 lean-burn conditions, the NGK LMAR8A-9 spark plug is mandatory. This long-reach plug ensures the flame kernel is positioned perfectly within the combustion chamber. The electrical system is supported by the YTZ10S battery, which provides the high cold-cranking amps (CCA) required for the Smart Key system and the idling-stop functionality.
Chassis and Safety
The SH 350 I’s handling is dictated by its tire pressures. With 16-inch wheels, maintaining 2.0 bar (29 psi) in the front and 2.25 bar (33 psi) in the rear is essential for the Honda Selectable Torque Control (HSTC) to function accurately. Incorrect pressures can lead to premature intervention of the traction control system during cornering.
Frequently Asked Questions
Q: How often should I check the coolant?
A: The coolant level should be checked every 4,000 km, though the long-life ethylene glycol should only require replacement every 2 years or 24,000 km.
Q: Can I use 10W-40 oil?
A: While 10W-40 may be used in emergency situations in hotter climates, Honda’s engineers specifically tuned the eSP+ engine for 10W-30 to maximize the efficiency of the internal oil jets.