The Therefore, it's essential to consult your motorcycle's owner's manual or contact a Harley Davidson dealership for accurate information tailored to your specific model and engine configuration.
That being said, most Harley Davidson motorcycles are designed to run on regular unleaded gasoline with an octane rating of 87 or higher. Higher octane ratings, such as premium unleaded gasoline with octane ratings of 91 or 93, are generally not necessary unless specified by the manufacturer for specific high-performance models or engine modifications.
Using a lower octane fuel than recommended can potentially cause engine knocking or pinging, which may lead to performance issues. However, using a higher octane fuel than necessary usually does not provide any additional benefits in terms of performance or fuel efficiency for motorcycles designed to run on regular unleaded gasoline.
To ensure the best performance and longevity for your Harley Davidson motorcycle, it's always best to refer to the owner's manual or consult with a Harley Davidson dealership for the specific octane rating and fuel requirements of your model.