5 Best Fuel Injector Cleaner for Harley Davidsons

If your Harley feels sluggish, stumbles on acceleration, or your fuel economy has dipped, your fuel injectors might be getting clogged with deposits. A quality fuel injector cleaner can restore performance and protect your engine.

This guide reviews five effective options, ranging from standalone additives to complete fluid kits, so you can choose the one that best matches your maintenance routine.

Royal Purple 18000 – Power Restorer

Royal Purple’s 18000 Fuel Injector Cleaner is a concentrated 6-ounce formula designed to restore fuel economy and maximize horsepower in your Harley. It’s particularly effective if you’ve noticed a drop in responsiveness after long storage or using ethanol-blended gas. The additive works in one treatment, helping clean injectors and stabilize fuel, so you get back that crisp throttle feel.

This cleaner is ideal when you want a simple, no-fuss additive that targets both performance and fuel system health. It pairs well with Royal Purple’s other products, but works fine on its own. Just pour it into a full tank and ride. Many riders report noticeable smoother operation after just one tankful.

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• Restores fuel economy
• Stabilizes ethanol
• Maximizes horsepower
• Improves responsiveness
• For use in both gasoline and diesel engines
• Fit type: Universal Fit

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Red Line SI-1 – Full System Cleaner

Red Line’s SI-1 Complete Fuel System Cleaner (60103) is a powerful 15-ounce additive that goes beyond just injectors. It’s engineered with both high- and low-temperature detergents to scrub deposits from injectors, carburetors (if your model has one), intake valves, and combustion chambers. That makes it an excellent choice if you want a thorough fuel system clean in one easy step.

Using it is simple: pour the entire bottle into your Harley’s gas tank and drive normally. The formula also enhances gasoline stability and reduces gum and varnish formation, which is helpful if your bike sits for periods. For riders who want a comprehensive clean without multiple products, this is a solid pick that delivers noticeable improvements in smoothness and fuel efficiency.

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• DESIGNED TO EXCEED EXPECTATIONS: Red Line complete SI-1 fuel system cleaner treatment for cleaning and preventing corrosion in fuel systems
• PERFORM AND PROTECT: Fuel additive cleans injectors, carburetors, valve and combustion chamber deposits with a powerful, concentrated blend of high-temp and low-temp detergents
• EFFICIENT FUEL BURN: Gas treatment that enhances gasoline stability, while reducing the build up of gum and varnish formation
• EASY TO USE: Use one bottle per tank for most effective treatment, additive cleans nearly 100% efficiency in one treatment
• 15 Ounce (2 Pack)

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Red Line 90226 – Complete Power Pack

The Red Line 90226 Big Twin Power Pack is a complete oil change kit for Harley-Davidson motorcycles with Evolution, Milwaukee-Eight, and Twin-Cam engines. It comes with five quarts of 20W50 motorcycle oil, one quart of V-Twin Transmission Oil with ShockProof, two quarts of primary chain case oil, and a separate bottle of fuel injection cleaner for powersports. This is the ultimate convenience package if you’re doing a full fluid service.

All components are tested to work together, so you don’t have to worry about compatibility. The included fuel injector cleaner targets deposits in your injectors, helping maintain performance. Perfect for riders who want one purchase to handle both oil and fuel system maintenance. Just note that if you only need a cleaner, this kit may be more than you need.

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• Complete kit for motorcycles equipped with Evolution, Milwaukee-Eight and Twin-Cam engines*
• 2007-up H-D motorcycle with the 96-inch and larger Twin Cam engines, users must purchase one extra bottle of Primary Chain Case Oil to meet this engine’s 38 oz (45 oz dry) capacity, compared to the 32 oz wet capacity of a Milwaukee-Eight, Evolution or V-Twin case
• Includes 5 quarts of 20W50 Motorcycle Oil, 1 quart of V-Twin Transmission Oil with ShockProof, 2 quarts of Primary Chain Case Oil, 1 bottle of Fuel Injection Cleaner for Powersports, a sticker kit, a Red Line Oil embroidered hat and a versatile funnel
• Each kit has been tested for compatibility and includes enough fluids for a complete oil change*
• Users must check vehicle specifications for capacity to ensure against overfilling, as full quarts may provide more product than necessary

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Red Line SI-1 15oz – Corrosion Fighter

This 15-ounce Red Line SI-1 (B000CPI5Z0) is a duplicate variant of the previous product but often available at a different price or packaging. It delivers the same premium fuel additive that cleans injectors, carburetors, valves, and combustion chambers using a powerful blend of detergents. It enhances gasoline stability and actively prevents corrosion, gum, and varnish formation inside your Harley’s fuel system.

You’ll notice smoother operation and increased power after a single treatment. It’s easy to use – just pour one bottle into a full tank. While it works well for routine maintenance, it may not be as aggressive on heavy buildup compared to some dedicated injector cleaners. For regular use to keep your system clean and corrosion-free, this is a reliable choice.

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• DESIGNED TO EXCEED EXPECTATIONS: Red Line complete SI-1 fuel system cleaner is a premium fuel additive, providing an effective fuel treatment solution to clean and prevent corrosion in fuel systems.
• PERFORM AND PROTECT: Fuel additive cleans injectors, carburetors, valve and combustion chamber deposits with a powerful, concentrated blend of high-temp and low-temp detergents
• EFFICIENT FUEL BURN: A gas treatment that enhances gasoline stability, while reducing the build up of gum and varnish formation, leading to smoother operation and increased power output.
• EASY TO USE: Use one bottle of Redline Fuel System Cleaner per tank for most effective treatment, additive cleans nearly 100% efficiency in one treatment
• ENAHNCED ENGINE EFFCIENCY: Experience improved fuel economy and engine performance with Red Line 60103 SI-1 Complete Fuel System Cleaner, as it effectively removes deposits, for enhanced exhaust system function

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HiSport IWP162 – Injector Replacement

The HiSport Racing Fuel Injector IWP162 is not a cleaning additive but a direct replacement for clogged or failing injectors on select Harleys. It fits 2001-2010 Softail, Dyna, FLH, and FLT models (not all submodels – double-check compatibility). It replaces the OEM part number 27609-01B and features a 4-hole design for more consistent, smoother fuel flow and better atomization.

If your injectors are physically damaged or beyond cleaning, this pack of two gives you a cost-effective fix. The metal and composite plastic construction includes internal seals that resist fuel exposure for longer life. Keep in mind, this is not a fuel additive – it’s a hardware upgrade. Best used when you’ve diagnosed injector failure and want reliable replacement parts.

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• [PRODUCT INFORMATION] – HiSport IWP162 fuel injectors pack in 2, 4 holes, made of metal & composite plastic, function more consistent and smoother, more accurate adjustment to account for extremes of cold temperatures，easier starting
• [FITMENT] – This fuel injection compatible with Harley Davidson series 2001-2010 Softail/Dyna/FLH/FLT , 2004-2005 Softail, 2001-2010 Dyna, 2001-2010, FLH, 2001-2010 FLT (Does not fit 2009 HD Super glide custom)
• [MANUFACTURER PART NUMBER] – This racing fuel injector is replaced with OE number IWP162, please verify manufacturer part number before ordering
• [HIGH CONTROL QUALITY] – HiSport fuel injectors Internal seal rings protected from fuel exposure, so can longer-lasting fuel injectors durability, meets OEM standards, 100% tested in the warehouse before shipping
• [WARRANTY] – All HiSport fuel injectors have 1 Year of guaranty. If it fails on your vehicle, please email us, we will reply within 24H.We would like to resolve your problem or you are not satisfied with the result.

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Buyer’s Guide: What to Consider

When picking a fuel injector cleaner for your Harley, focus on detergent strength, compatibility, ease of use, and whether it also cleans the rest of the fuel system.

• Detergent Type: Look for high-temperature and low-temperature detergents that remove deposits from injectors, valves, and combustion chambers.
• Engine Compatibility: Check if the cleaner is safe for your specific Harley engine — Evolution, Twin-Cam, or Milwaukee-Eight models.
• Ease of Use: Choose a product that simply requires adding one bottle per tank — no complex steps or special tools needed.
• Additional Benefits: A good cleaner should also stabilize ethanol-blended fuels and prevent gum, varnish, and corrosion buildup.
• Kit vs. Solo: If you prefer all-in-one convenience, consider a comprehensive oil change kit that includes a fuel injector cleaner.

Conclusion

Using a quality fuel injector cleaner regularly helps your Harley maintain smooth idling, crisp throttle response, and good fuel economy. The right choice depends on whether you want a standalone treatment or a complete fluid change package.

For a strong, standalone cleaner, the Royal Purple 18000 or Red Line SI-1 work great. If you’re due for an oil change, the Red Line 90226 kit gives you everything plus the cleaner.