Fork oil change

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Jan 8, 2009 | 10:47 AM

#21

tmitchellof PG

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Joined: Sep 2006

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From: Punta Gorda,FL

What do you guys mean by the oil was filthy? Do you mean it was a darker color, or was there stuff floating around in it? I would think that when HD assembles the forks, they may use some type grease or graphite lube that will mix into the oil and cause it to darken.
It is a closed system, so I would think it would take quite a while for the oil to degrade.
Tom

Jan 8, 2009 | 10:50 AM

#22

anubisss

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Joined: Jan 2006

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From: Los Angeles, CA

I ahve not done mine since 20k. Guess it's time again. Back to the dealer for the 3rd day in a row...

Jan 8, 2009 | 10:53 AM

#23

Da Gumpmeister

Ultimate HDF Member

Joined: Dec 2007

Posts: 8,642

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From: Forest Lake, Mn

Quote:

Originally Posted by beracing

Gump
I've got an 09' FLHX, I've noticed bottoming out of the shocks when I hit a hard bump. I know Harry has his shock package, which sounds great, but I don't have the mula to make that jump yet. If I up the shock oil to a heavy oil, should that stiffen it up a little to give a little more dampening? I'm not a bean pole, but a buck eighty dressed out...

Just curious in your opinion...

Definitely try the heavier oil BEFORE you revalve the front end. Solves 90% of probs in your case.

Re-iterate - when you drain it, USE the # of oz. for your scoot. IF you jus' do the 'visual' measure, you are 'assuming' that what you had in there was correct from the git-go. NOT always true, Grasshopper. PLUS, there is a REASON they give it to you in EXACT #'s, IE: 7.75, 8.25, etc. and why there is a tool to measure it precisely.
Now visualize driving down the road on TWO different pogo sticks.
BUT to each their own.

IF'n you have a mind to, jus' conduct your own experiment. Pull the plug on one tube. Let out some of the oil. NOW git on, head down the hiway at 50 or so. DO A PANIC STOP like a car pulled out.
And I have changed out oil in NEW bikes, different amount in the tubes from the factory. NOT GOOD.
BUT again, your ride, your ****.

Oh H*LL, let's jus' go back to springers and skip this oil thang.

MODERN, bah humbug.

Jan 8, 2009 | 11:02 AM

#24

Baeseman1

Elite HDF Member

Joined: Aug 2007

Posts: 4,265

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From: Northern VA

Quote:

Originally Posted by tmitchellof PG

What do you guys mean by the oil was filthy? Do you mean it was a darker color, or was there stuff floating around in it?

It's hard to explain, but it wasn't right. Kind of a yellow and milky-ish color. I have a set of chrome sliders to install, so I'll be able to update if the 15w bel-ray fork oil was any different than factory.

Jan 8, 2009 | 11:03 AM

#25

1Coastie

Road Master

Joined: Oct 2007

Posts: 786

Likes: 1

From: Sheridan, AR

Quote:

Originally Posted by tmitchellof PG

The oil was black, and looked like it was water impregnated. Very dirty.
If you think about it, its not really a "closed system". The fork sliders are constantly exposed to dirt and water, they slide up and down in and out of the fork oil, and you can be sure they constantly carry microscopic particles of that dirt and moisture past the seals and into the oil.
Its your bike, don’t change it if you don’t want too, but you WILL be changing fork seals a hell of a lot sooner than I will.
Fork oil is cheap and easy to change. Fork seals are a pain in the a$$ to replace. It's your call.

Jan 8, 2009 | 11:07 AM

#26

sniper77

Outstanding HDF Member

Joined: Sep 2007

Posts: 3,352

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From: Augusta, GA

I'm telling ya, @ 10K the oil in my forks looked like it had been cooked on the stove.

I cleaned all the parts before putting THE EXACT AMOUNT of oil into each fork and the ride was night and day different. That lesson taught me that I will change it every other oil change (10K) without fail.

Jan 8, 2009 | 11:15 AM

#27

Gutman

Road Master

Joined: Nov 2006

Posts: 1,227

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From: Central Illinois

Quote:

Originally Posted by KBFXDLI

If you use a synthetic fork oil you will be able to go much further between changes. I know redline makes it. Not sure about the other companies.

This isn't true. the fork oil is under higher shear strenth from increased hydraulic pressure. The synthetic oils have better properties than the fish based factory oils but still recommend changing at 25k.

Quote:

Originally Posted by hpfatboy

Yes change it out, use the SE HEAVY FORK OIL. Put a container under fork drain plug, and mark how much oil comes out on the container. Just add the same amount as you took out is the easiest method.

Don't do this. Follow the recommended replacement levels for wet or dry in the manual. The oil also lubricates the bushings and sliders. A very light oil film is maintained on the fork tube and some fluid loss is normal over time. If you replace the same level drained all the time you will be constantly lowering the oil level. Stick to the manual.

I remember when Evo's recommendations were every 10,000 miles or annually. The oil out of some of those forks were black. The oil and seals have been improved is why the interval increased. 25-30k is long enough. Change it.