Changing fork oil

[captaindan]

I see a lot of discussion in several forums on changing fork oil. My question is, how often do you change your fork oil and why. In 35 years of riding, this just hasn't been a big priority. Am I missing something? Does the oil break down or is the change just to put in a different type. I think the only time I have changed mine on any bikes is to replace the seals. All the other fluids I change regularly. Thanks and Merry Christmas to all and a blessed and safe New Year.

 

[joedrum]

to me if its not leaking its fine ,,,,but on the roads i travel ...lots of gravel roads...the seals go out a lot and changing oil is is part of seal change

 

[dan filipi]

I never could understand the reasoning for changing fork oil other than what you said, like to change to a different grade or when doing seals.
Afterall, the shocks work with the same principal, we never change fluid in them.

 

[bk2valve]

I agree....as long as you know the level is still the proper amount. I wonder though because every fork I have pulled apart to do seals, has had a lot of black dirt in it. I assume it is from bushing wear....what do you guys think? Myself, I don't change the oil unless I do the seals.

Oh yeah almost forgot, since I have the Steerite triple tree conversion in order to shorten the trail on my sidecar rig, I have been told to replace fork slider bushings when I do seals...there is more wear on the bushings due to the more radical angle. I think I have done it once in 40 or 50 some thousand sidecar miles.
Brian

 

[AApple]

The oil will break down over time...that's where the black goo comes from. Sealed shocks use a different type of oil, but even that breaks down eventually....that's usually when the shocks need replacing. If you've ever taken the pan off of an automatic trans that was working fine, and just needed a fluid/filter change as part of normal maintenance, you prolly noticed the blackish film on the bottom of the pan. That's fluid that has just worn out....the additives have fallen out of suspension, so to speak.
I can totally see the need to service fork oil at some point in service. I might even do mine one of these days!

 

[cyborg]

change mine once a year at the beginning of riding season, along with the rest of my normal maintence

 

[captaindan]

Ok, so it sounds as if we're on a wide spectrum. I myself don't change the oil regularly if at all. Does anyone replace seals before they go bad say as preventive maintenance. If so, how many miles under standard driving conditions. The seals on my 82 didn't start leaking until I took it out of storage. I have never replaced them in 159,000 miles. I honestly can't recall if I ever changed the oil. Maybe I was just darn lucky. I owned a Honda 750K that I changed the seals at least once before it hit 75,000 miles.

 

[89-300ce]

I think ATF is good for a long, long time. The after market fork oils break down just like the motor oil they are based on and will need to be changed out regularly.

 

[slabghost]

Like most I never really thought about it. Never have changed fork oil. Now that I think on it though. Humidity will get in and cause condensation over time. I'm thinking it's time to gain a new habit.