# Fulbat FB4L-B · Motorcycle battery 12V 4.2Ah 56A

![Fulbat FB4L-B · Motorcycle battery 12V 4.2Ah 56A](https://bateriasonline.es/386-home_default/fulbat-fb4l-b.jpg)

> Fulbat FB4L-B: 4.2 Ah motorcycle battery, 56 A (EN), 120×70×92 mm, positive terminal on the right. Price on request: ask for a free quote.

**Category:** [Motorcycle batteries](https://bateriasonline.es/en/motorcycle-batteries) → [Fulbat](https://bateriasonline.es/en/fulbat-batteries)

- **Canonical URL**: https://bateriasonline.es/en/fulbat-fb4l-b
- **Language**: en
- **Brand**: Fulbat
- **Reference**: BOL-FULBAT-FB4L-B
- **MPN**: FB4L-B
- **Last updated**: 2026-10-27

## Technical specifications

| Feature | Value |
|---|---|
| Brand | Fulbat |
| Range | FULBAT Motorcycle DRY |
| Application | Motorcycles |
| Technology | Lead-acid |
| Voltage | 12 V |
| Capacity | 4.2 Ah |
| Cold cranking amps (EN) | 56 A |
| Length | 120 mm |
| Width | 70 mm |
| Height | 92 mm |
| Weight | 1.6 kg |
| Polarity | Positive terminal on the right |

## Quick description

Fulbat FB4L-B: motorcycle battery with 12 V, 4.2 Ah and 56 A cold cranking current, measuring 120 × 70 × 92 mm, with the positive terminal on the right.

## Description

## Where the Fulbat FB4L-B fits

The Fulbat FB4L-B is made for motorcycles, scooters and quads. With 4.2 Ah, the FB4L-B suits motorcycles and scooters that had a battery of that capacity.
At 4.2 Ah it is a small battery, typical of 50 to 125 cc scooters and light motorcycles. The FB4L-B belongs to the Fulbat FULBAT Motorcycle DRY range. [More Fulbat batteries](https://bateriasonline.es/en/fulbat-batteries)

## Fulbat FB4L-B codes and part numbers

Shops, garages and catalogues identify the FB4L-B with these codes:

| Commercial reference | FB4L-B |
|---|---|
| Not to be confused with | Fulbat FB3L-B (3.2 Ah, 32 A), Fulbat FB5L-B (5.3 Ah, 65 A), Fulbat FB9L-B (9.5 Ah, 115 A) |

## Equivalents and alternatives to the Fulbat FB4L-B

No other reference in the catalogue fully matches the dimensions and polarity of the FB4L-B; you will find the closest ones among our [motorcycle batteries](https://bateriasonline.es/en/motorcycle-batteries).

## Fulbat FB4L-B vs FTX4L-BS and FTX5L-BS: differences

The real differences between the FB4L-B and the closest Fulbat models:

| Model | Capacity | Cold cranking (EN) | Dimensions (mm) | Positive | Weight |
|---|---|---|---|---|---|
| Fulbat FB4L-B (this one) | 4.2 Ah | 56 A | 120 × 70 × 92 | right | 1.6 kg |
| Fulbat FTX4L-BS / FTZ5S-BS | 4.2 Ah | 50 A | 113 × 70 × 85 | right | 1.43 kg |
| Fulbat FTX5L-BS | 4.2 Ah | 80 A | 113 × 70 × 105 | right | 1.78 kg |

- Fulbat FTX4L-BS / FTZ5S-BS: the same capacity, 6 A less cranking power, a different case (113 × 70 × 85 mm), AGM technology.
- Fulbat FTX5L-BS: the same capacity, 24 A more cranking power, a different case (113 × 70 × 105 mm), AGM technology.

## Check this before ordering the Fulbat FB4L-B

- Check the EN amps on your battery: if it says 56 A or less, the FB4L-B covers your engine.
- Capacity of the FB4L-B: 4.2 Ah; the same as your current battery or slightly more is fine.
- The FB4L-B has the positive terminal on the right: compare it with your current battery.
- Length, width and height of the FB4L-B: 120 × 70 × 92 mm.

## Frequently asked questions about the Fulbat FB4L-B

### Fulbat FB4L-B or FTX4L-BS / FTZ5S-BS?

Compared with the FB4L-B, the Fulbat FTX4L-BS / FTZ5S-BS has 6 A less cranking power and AGM technology. The FB4L-B cranks harder; the FTX4L-BS / FTZ5S-BS is only a good option if your original battery says 50 A or less. Mind the space: the FTX4L-BS / FTZ5S-BS measures 113 × 70 × 85 mm.

### How much does the Fulbat FB4L-B weigh?

The FB4L-B weighs 1.6 kg. For reference, the Fulbat FTX4L-BS / FTZ5S-BS (4.2 Ah) weighs 1.43 kg.

### Which side is the positive terminal on the Fulbat FB4L-B?

The FB4L-B has the positive terminal on the right, looking at the battery from its long side with the terminals closest to you.

## Inside the FB4L-B: lead-acid technology

Inside, the FB4L-B is classic lead-acid: liquid electrolyte and lead plates. It is a robust, well-known technology with a good capacity-to-price ratio, and still the basis of most cars, trucks and traction equipment.

## Keep comparing: alternatives to the FB4L-B

- [More motorcycle batteries](https://bateriasonline.es/en/motorcycle-batteries)
- [Full Fulbat catalogue](https://bateriasonline.es/en/fulbat-batteries)

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*bateriasonline.es — Batteries and accessories · 2026-11-10*