Oil Filter By-Pass Spring Setting For Harley-Davidson Engines?

A reader asks: Regarding AMSOIL oil filters for Harley-Davidson engines. What is the by-pass spring setting on these filters?

Our answer: AMSOIL Tech Services tells us that the by-pass spring pressure setting on both the EAOM134 (black) and EAOM134C (chrome) is 11-17 PSI. This may seem like a wide margin, but that’s the only number they offer for publication.

Technical Services also mentioned that in Harley-Davidson engines, the filter would have to completely plug to send it into by-pass mode. With millions of miles logged by our customers, they have never ever heard of this happening.

Normal operation would never put these filters into by-pass.

The Milwaukee-8 and many Twin-Cam engines use the AMSOIL EAOM134 oil filter.

About AMSOIL Ea Motorcycle Oil Filters

The heart of these oil filters is the world-class synthetic media. It delivers elite small particle removal. In addition, heavy-duty parts were chosen to construct the rest of these units. All of this makes AMSOIL filters a great match for any V-Twin engine.

Other Motorcycle Oil Filter Shopping Considerations

Don’t get caught up with searching for the longest possible filter. See our article about Why Harley-Davidson Released A Longer Oil Filter For the Milwaukee-8 Engine.

Also, be careful when comparing oil filter efficiency numbers. These numbers are not always what they seem. Efficiency numbers can be measured on different scales. Therefore, the numbers offered by two different filter makers can be apples and oranges. See the article Do Harley-Davidson Oil Filters Really Filter Down To 5-Microns?.

To sum up, the by-pass spring setting on motorcycle oils filters is not a major concern when choosing a filter. The by-pass spring setting will be in the proper range if the filter is designed for your application. It is far more important to look for sturdy construction and a high-quality filter media.

To find the correct oil filter for your Harley engine, see our application guide.

Related: Our Harley-Davidson Article Compilation 

Questions? Contact us using the form on this page or call us at 1-800-748-5781.