Purpose and Specifications

LIQUI MOLY Motorbike HD-Classic SAE 50 Street 4L is a premium engine oil designed for classic motorcycles with high-displacement air-cooled engines. This thick SAE 50 viscosity oil stays reliable in hot running conditions up to 120°C, forming a tough protective film that cuts friction and prevents metal-on-metal wear during long rides or heavy loads.

Practical benefits include smoother engine operation, reduced fuel and oil use, and longer part life in older bikes. The 4L container suits most classic street bikes, providing full protection for wet clutches without slippage. Shelf life is 5 years when stored cool and dry.

When to Use / Replace?

• Use for classic air-cooled engines in street riding, especially in warm climates or high-speed runs over 170 km/h where oil thinning is a risk.
• Replace every 5,000-6,000 km or yearly in city traffic, short trips under 8 km, or stop-and-go driving to avoid acid buildup and engine damage.
• Change before winter storage to protect against corrosion, and add fresh oil plus additive after long layups for startup protection.

FAQ

Is SAE 50 too thick for cold starts? No, it flows well above freezing and excels in hot engines over 80°C, prioritizing high-temp stability for classics over quick winter starts.

How often should I change it under heavy use? Every 5,000 km or sooner if riding dusty roads, towing, or idling a lot – always check your dipstick for dark color or low level.

Can I mix it with other oils? Best to use alone for full benefits, but compatible with most mineral oils; flush first for oldest engines.