Check the Negative (-) terminal clamp is tight
Check the Positive (+) terminal clamp is tight. CAUTION If using a spanner to tighten terminal, be careful not to short the spanner on the bodywork
Check battery is generally secure. If loose, tighten the battery retainer
The battery retaining clamp position
To tighten, a 13mm socket is needed. Not too tight because you may damage the battery casing
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