Get all the answers to your Fork Oil questions!

Every motorcycle eventually needs its fork oil changed.  Depending on what and how you ride, you may have a few options to choose from for replacement fork oil.  Should you go with a lighter oil?  Or perhaps a heavier oil?  With so many options available, there are many considerations.  You’ll have to consider the function of the fork oil, your preference, and what replacement brand of oil you’re buying.

AMSOIL Shock Therapy

What Fork Oil Does

The fork is a vital component of the ride quality of your motorcycle.  Inside each fork is valving that controls the compression and rebound of the fork.  Two motions are involved: going up and down, or in and out.  The oil inside the fork works directly with the valves to provide consistent damping when you’re riding.  It controls the fork spring’s energy and converts it to heat that the fork oil absorbs.  It does this without regard for temperature, terrain, or what type of motorcycle you choose to ride.  The function is the same.

Why Viscosity Should Matter to You

Knowing the function of the fork oil, you should be worried about what oil viscosity is used on your motorcycle. AMSOIL offers two replacement fork oils: #5 light weight, and #10 medium weight.  Each offers excellent protection for heat tolerance and damping fade over time.  But they also offer a slightly different riding characteristic.

AMSOIL #5 light viscosity fork oil is meant for more rapid compression and rebound of the suspension.  It’s perfect for off-road riding where you jump and need quick control upon landing.  It’s also perfect when you need quick response to every bump, log, and jump in your path.

The AMSOIL #10 medium viscosity fork oil is a thicker oil that is better suited to slower compression and rebound.  This may be something like a cruiser that you ride cross-country or a sportbike that you race on a closed course.  It can even be for an ATV you use on your farm. Both fork oils offer significant performance over bargain brands.

How Often Do I Change My Fork Oil?

This question is tricky to answer with a general number of miles or time in use.  If you’re looking for a number of miles, 5,000 seems to be a general number accepted by riders.  Concerning time, you may find that the fork oil should be changed every couple of years depending how often you ride.  Miles may be a good option to track for maintenance on your street riding motorcycle, but time in use may be better for your off-road equipment that doesn’t use a speedometer and odometer.

How you determine the frequency to change your fork oil will be up to you, but in either case mentioned, you should feel a significant change in the performance of the oil at the end of its life.  The oil absorbs heat generated during the suspension compressing and rebounding, and over time it will lose some of its ability to stay consistently flowing.

Why Should I Choose AMSOIL Over Another Brand?

Your fork oil will need to be replaced, and there’s no way to get around that fact.  The question is if you want the best fork oil for consistency over its life.  Of course you do!  AMSOIL #5 and #10 fork oils offer extreme protection against corrosion and wear of your metal and rubber components inside of your fork.  You shouldn’t be worried if you will eventually have to do more maintenance because of a poor oil choice.  With AMSOIL you won’t.

AMSOIL Shock Therapy #5 and #10 Suspension Fluid also has a high viscosity index (VI). A higher viscosity index offers better resistance to viscosity changes as the temperature changes.  This is the functional consistency you want and need in your motorcycle, ATV, and snowmobile suspension.

Any Last Considerations Before Buying AMSOIL Shock Therapy Suspension Fluid?

Some will claim that fork oil is just fork oil, and any brand will offer the same performance.  Consider this before buying another brand: There isn’t a standard viscosity index similar to engine oil.  One brand may offer a light and medium viscosity oil also, but their version may be completely different from AMSOIL.  Your motorcycle may ride harsh with minimal damping, or change to a sluggish suspension that is uncomfortable to ride.  If you like AMSOIL, stay with AMSOIL.

You should be setting your motorcycle up for your riding style, your body weight, and any accessories you ride with.  Changing fluids, even if it saves you a few dollars, may change the suspension enough that you won’t enjoy riding anymore.  Lastly, always compare shock fluid characteristics at 40ºC if you are comparing brands to AMSOIL.  Brands that offer similar characteristics at 40ºC will feel comparable in performance.  Many manufacturers release product data bulletins for their shock oils, which will allow you to compare different brands from the comfort of your garage.

Replacing Your Fork Oil

Searching for the best replacement fork oil can be a complicated endeavor with a few key words on a search engine returning page after page of results.  When your motorcycle, ATV, or snowmobile start to feel different, a fork or shock oil change could be a simple way to return the consistent feel you expect.  If you have questions on what oil viscosity you need, which type would be best, or want to add in a few maintenance items, we’re here to help!  Contact us at Buy Great Oil and we’ll get you started in the right direction.  We’re your local AMSOIL dealer, and are here to help you keep your vehicle and power equipment fully maintained.

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