# Motobatt MBTX20UHD · Motorcycle battery 12V 21Ah 310A

![Motobatt MBTX20UHD · Motorcycle battery 12V 21Ah 310A](https://bateriasonline.es/3264-home_default/motobatt-mbtx20uhd.jpg)

> Motobatt MBTX20UHD: 21 Ah motorcycle battery, 310 A (EN), 175×87×155 mm, AGM. Equivalent to Varta YTX20H-BS and Varta YTX20HL-BS.

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

- **Canonical URL**: https://bateriasonline.es/en/motobatt-mbtx20uhd
- **Language**: en
- **Brand**: Motobatt
- **Reference**: BOL-MOTOBATT-MBTX20UHD
- **MPN**: MBTX20UHD
- **Price**: 146,02 € (VAT incl., Spain)
- **Last updated**: 2026-11-09

## Technical specifications

| Feature | Value |
|---|---|
| Brand | Motobatt |
| Range | MOTOBATT QUADFLEX |
| Application | Motorcycles |
| Technology | AGM |
| Voltage | 12 V |
| Capacity | 21 Ah |
| Cold cranking amps (EN) | 310 A |
| Length | 175 mm |
| Width | 87 mm |
| Height | 155 mm |
| Weight | 6.5 kg |
| JIS code | YTX20 BS YTX20 LBS YTX20 HBS YB16 B YB16 LB YB16 CLB |

## Quick description

Motobatt MBTX20UHD: motorcycle battery (AGM) with 12 V, 21 Ah and 310 A cold cranking current, measuring 175 × 87 × 155 mm.

## Description

## Who the Motobatt MBTX20UHD is for

The Motobatt MBTX20UHD is a motorcycle starter battery: compact, vibration-resistant and with just the right power to turn the starter motor and feed the electronics. It handles frame vibration and idle periods better than an adapted car battery.
At 21 Ah it is a large battery for heavy motorcycles, jet skis and utility quads. The MBTX20UHD belongs to the Motobatt MOTOBATT QUADFLEX range. [The full range of Motobatt batteries](https://bateriasonline.es/en/motobatt-batteries)

## Motobatt MBTX20UHD codes and part numbers

The MBTX20UHD is listed under these codes on labels, in garages and in catalogues:

| Commercial reference | MBTX20UHD |
|---|---|
| Not to be confused with | Motobatt MBTX30UHD (32 Ah, 385 A) |

## Equivalents and alternatives to the Motobatt MBTX20UHD

As the MBTX20UHD is an AGM battery, we only list other AGM batteries with its dimensions and polarity: neither an EFB nor a conventional battery can replace it.

| Model | Technology | Capacity | Cold cranking (EN) | Dimensions (mm) |
|---|---|---|---|---|
| Varta YTX20H-BS | AGM | 18 Ah | 320 A | 175 × 87 × 154 |
| Varta YTX20HL-BS | AGM | 18 Ah | 320 A | 175 × 87 × 154 |
| Varta TX20H (FA) | AGM | 18 Ah | 310 A | 176 × 89 × 154 |
| Varta TX20HL (FA) | AGM | 18 Ah | 310 A | 176 × 89 × 154 |
| Motobatt MBTX20U | AGM | 21 Ah | 310 A | 175 × 87 × 155 |

## Motobatt MBTX20UHD vs MB18U and MB16U

The real differences between the MBTX20UHD and the closest Motobatt models:

| Model | Capacity | Cold cranking (EN) | Dimensions (mm) | Weight |
|---|---|---|---|---|
| Motobatt MBTX20UHD (this one) | 21 Ah | 310 A | 175 × 87 × 155 | 6.5 kg |
| Motobatt MB18U | 22.5 Ah | 280 A | 180 × 90 × 162 | 6.8 kg |
| Motobatt MB16U | 20 Ah | 240 A | 160 × 90 × 161 | 5.9 kg |

- Motobatt MB18U: 1.5 Ah more, 30 A less cranking power, a different case (180 × 90 × 162 mm).
- Motobatt MB16U: 1 Ah less, 70 A less cranking power, a different case (160 × 90 × 161 mm).

## What to look at before buying the MBTX20UHD

- The MBTX20UHD delivers 310 A cold cranking (EN standard); do not go below what your original battery states.
- Your current battery should say about 21 Ah; a little more is also fine.
- Length, width and height of the MBTX20UHD: 175 × 87 × 155 mm.

## Frequently asked questions about the Motobatt MBTX20UHD

### Motobatt MBTX20UHD or MB18U?

Compared with the MBTX20UHD, the Motobatt MB18U has 1.5 Ah more and 30 A less cranking power. The MBTX20UHD cranks harder; the MB18U is only a good option if your original battery says 280 A or less. Mind the space: the MB18U measures 180 × 90 × 162 mm.

### How much does the Motobatt MBTX20UHD weigh?

The MBTX20UHD weighs 6.5 kg. For reference, the Motobatt MB18U (22.5 Ah) weighs 6.8 kg.

### Which battery is equivalent to the Motobatt MBTX20UHD?

Only other AGM batteries with its dimensions and polarity: Varta YTX20H-BS, Varta YTX20HL-BS and Varta TX20H (FA). Neither an EFB nor a conventional battery replaces the MBTX20UHD.

### Which charger does the Motobatt MBTX20UHD need?

A charger with an AGM mode that limits voltage to about 14.4-14.7 V. Never an old unregulated charger: overcharging dries out an AGM beyond repair.

## Inside the MBTX20UHD: AGM technology

The MBTX20UHD is AGM: the electrolyte is absorbed in glass fibre mats, so it is sealed and spill-proof. It withstands many more cycles than a conventional lead battery, at the cost of being more sensitive to overcharging.

## Other options if you are unsure about the MBTX20UHD

- [More motorcycle batteries](https://bateriasonline.es/en/motorcycle-batteries)
- [Full Motobatt catalogue](https://bateriasonline.es/en/motobatt-batteries)
- [Varta YTX20H-BS](https://bateriasonline.es/en/varta-ytx20h-bs-518908032) · 18 Ah, 320 A, 175×87×154 mm
- [Varta YTX20HL-BS](https://bateriasonline.es/en/varta-ytx20hl-bs-518918032) · 18 Ah, 320 A, 175×87×154 mm

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