Should You Use Premium Gas In A Harley-davidson?

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While Harley-Davidson motorcycles whitethorn person erstwhile been nan domain of scruffy counterculture types and moreover pack members, to ain a caller Harley nowadays takes a heavy wallet. The slightest costly of nan classical "big twin" lineup, nan Street Bob, carries a suggested value of $15,999 pinch zero options. That tin easy balloon to much than $45,000 for a top-of-line touring motorcycle for illustration nan CVO Road Glide ST aliases nan $110,000 limited-edition CVO Road Glide RR that lets you dress you're successful your very ain King of nan Baggers race. 

The bully news is that arsenic Harley prices person escalated, truthful has performance. For nan 2025 exemplary year, nan latest Milwaukee-Eight bid of V-twins bring betwixt 98 and 153 horsepower to nan party. To execute that, a reasonably precocious compression ratio betwixt 10.3:1 and 11.4:1 is utilized. That, friends, calls for premium fuel. And indeed, a speedy browse done nan Bar and Shield's charismatic owner's manual confirms arsenic much; a minimum pump octane standing of 91 is required for each caller Harley we researched, including nan brand's Revolution Max-powered models for illustration nan Sportster S and Nightster. 

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So far, we've covered nan octane requirements of caller Harley-Davidson products, but what if you're nan proprietor of an older bike, for illustration 1 pinch a twin-cam motor that ran from 1999 to 2017? Know that nan owner's manual for those years besides specifies minimum 91-octane gasoline. By nan way, if you can't find your owner's manual, Harley provides an online transcript — on pinch loads of different useful info — astatine its Service Information Portal.

In nan past, Jalopnik has written extensively astir whether to usage premium fuel, truthful we're not going to recap each of that worldly here. Suffice it to opportunity that successful high-performance, high-compression engines, premium state prevents knocking and pinging that tin harm your engine. That said, modern engines person blase machine controls that consciousness lower-octane substance and set nan ignition timing and sometimes different factors to forestall specified damage. However, this protection against lower-octane gasoline will handicap the engine's maximum performance.

According to AAA, premium substance costs an mean of 86 cents much per gallon than regular. When pumping 20 gallons into your car aliases truck, that equals astir $17 other for premium gas, which is not insignificant. On nan different hand, motorcycles person overmuch smaller substance tanks and typically get overmuch amended substance system than astir cars and trucks, truthful giving your motorcycle nan champion could costs little than a specialty coffee.