Yuasa Motorbike battery 12N5.5-4A-DC / 12N5.5-4A 12V 5.5Ah (Conventional / Acid)

The Yuasa 12N5.5-4A (often with the suffix "DC" for Dry Charged) is a classic, conventional lead-acid battery. It was specially developed for older motorcycles from the 70s and 80s, especially for smaller to medium displacements. With a capacity of 5.5 Ah (10h), it offers the authentic technology and exact dimensions necessary for the preservation and operation of youngtimers and classic bikes. As a "standard" battery, it is serviceable and designed for longevity with correct maintenance.

Highlights at a Glance

• Classic technology: Proven lead-acid technology ("wet battery") that harmonises perfectly with the charging systems of older motorcycles.
• Dry Charged (dry pre-charged): The battery is delivered dry and can be stored indefinitely. The chemical reaction only starts the moment it is filled with acid (activation).
• Extremely slim format: With only 60 mm width, it fits in the special, narrow battery boxes of many old Japanese two-strokes (e.g. Yamaha RD/DT), where wider modern batteries would not fit.
• Serviceable: Thanks to the accessible sealing plugs on the top, the fluid level can be checked and topped up with distilled water if needed – important for long service life.
• YuMicron advantage: Utilises special glass mat separators to damp vibrations and stabilise performance compared to standard batteries.
• Venting: Features a side connection for a vent hose to safely vent gases out of the vehicle.

The classic for Yamaha two-strokes

The 12N5.5-4A is legendary in the world of classic two-stroke motorcycles. It is the standard battery for icons such as the Yamaha RD 250 / 350 / 400 (air-cooled), the Yamaha DT 125 / 175 / 250 / 400 enduros and various Kawasaki KH models (three-cylinder). These motorcycles require exactly this slim format (135 x 60 mm) to fit in their frames.
 

Characteristics

FAQs about the Yuasa 12N5.5-4A

What is the difference to the 12N5.5-3B?

Different terminal arrangement and venting: Both batteries have 12V and 5.5Ah as well as the same dimensions. The difference is in the arrangement of the terminals and the vent hose.

• 12N5.5-4A (your battery): Positive terminal right, vent right.
• 12N5.5-3B: Positive terminal right, vent left (and terminals often reversed/differently positioned). Be sure to check on which side your motorcycle requires the vent hose and the cable connections. The hose must not be laid across the battery.

Is acid included?

Depends on the dealer: Due to legal regulations (EU regulations), end customers are often not allowed to receive separate acid packs any more. Many dealers therefore send the battery already filled and activated. If you buy it in the shop, you often get it dry with an acid pack ("DC" = Dry Charged) and have to fill it yourself.

Do I need to top up water?

Yes, check regularly: As this is an open lead-acid battery, water evaporates during operation. Check the level 1-2 times per season. Top up only with distilled water if necessary (never refill with acid, except on first filling!).

What is the hose on the side for?

Safety venting: This is the overflow hose. It must be connected and routed so that it leads under the motorcycle into the open air (not onto the exhaust or chain!). Because the battery releases gas and acid droplets can escape, the hose prevents corrosion damage to the frame.