The Honda FourTrax 300 generally uses a 12-volt lead-acid battery, most often the YTX12-BS style with roughly 11–12 Ah; exact size depends on the year and variant, so verify against your specific model’s manual or the battery label.
The FourTrax 300 line spans several years and trims, including 2WD and 4WD configurations. Replacement batteries can vary slightly in dimensions or terminal layout, so it’s important to confirm the exact specification for your ATV before buying a replacement.
Common battery sizes used in Honda FourTrax 300 models
The TRX300 family has seen a few different batteries across its production run. Here are the sizes you’re most likely to encounter. Verify against your current battery or the official manual for your exact year and trim.
- YTX12-BS — 12-volt lead-acid battery, typically around 11–12 Ah; the most common OEM/replacement choice for many TRX300 variants.
- YTX9-BS — 12-volt battery with roughly 8–9 Ah; may appear in some smaller or earlier configurations; ensure you have enough space and similar terminal layout.
- YTX14-BS — 12-volt battery with about 12–14 Ah; higher capacity; may require more tray space or a slightly different fit in some models.
In practice, YTX12-BS is the standard starting point for most Honda FourTrax 300 bikes, with alternative sizes used only for specific years or trims. Always confirm with your bike’s documentation or a parts fiche.
How to determine the exact size for your bike
To ensure you select the correct battery size for your particular TRX300, follow these verification steps. This helps avoid fitment issues and starting problems in varying climates.
- Check the battery label on your current unit for the exact model number (for example, YTX12-BS) and its capacity (Ah) and CCA.
- Consult the owner’s manual or Honda parts fiche for your year and trim to confirm the recommended battery type and capacity.
- Measure the current battery’s dimensions (length, width, height) and compare them with the replacement’s specifications to ensure it fits in the battery tray and with the battery area cover.
- Note the terminal arrangement (which side the positive and negative terminals sit on) so the replacement matches your wiring harness and cables.
- Consider if you want to upgrade to an AGM or GEL style battery, but ensure the charging system and tray will accommodate the different size or venting requirements.
- If in doubt, contact a Honda dealer or use a reputable parts cross-reference service with your VIN to confirm the exact spec.
These checks help you pick the correct size and avoid common issues like a loose fit, terminal misalignment, or insufficient starting power.
Installation and care tips
Once you have the right battery, proper installation and maintenance keep your FourTrax starting reliably in all conditions. Use the correct polarity, secure the battery in the tray, and apply terminal grease to prevent corrosion. Keep the battery charged using a suitable charger, especially if the ATV sits unused for long periods.
Summary
For most Honda FourTrax 300 models, a 12-volt lead-acid battery is used, with YTX12-BS being the typical replacement choice (approximately 11–12 Ah). Exact size depends on the year and trim, so verify with your owner’s manual, current battery label, or a trusted parts reference. When in doubt, match the model number, capacity, and terminal layout to ensure a proper fit and reliable starting performance.