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Garage Basics
Fork Oil Change

Fork Oil Change

If you have to shrug, when the term fork oil pops up, and turn back to the work on your bench, you are probably the guy who has a springer, girder or leaf spring fork in his chop, and generally keeps to Harleys before the 1949 vintage.

1949 is the year when Harley-Davidson introduced the red-hot Panhead "Hydra Glide" motorcycle, which came with a "hydra-ulic" front end. Steel tubes sliding on steel tubes, and deep down inside long springs swimming in oil raised the riding comfort to unheard of levels, reducing back-breaking potholes, back then a daily menace to riders, to minor bumps in the road.

With all this sliding action going on, it’s no wonder the oil gets tired and saturated with microscopic metal particles due to abrasion, which makes regular change a necessity. The viscosity of fork oil can be used to adjust the damping characterisics (and levels of comfort) of hydraulic forks. SAE 30 W was standard on HDs up to 1978 (and up to ’84 on FL models). 30 weight is rather stiffish by today’s standards. It was replaced by 20 W later. If you appreciate a soft ride, go down to 15 W, or concoct your own "viscocktail" by mixing different viscosities. Make sure that you remember the mix ratio for next time.

Model specific quantities, the maintenance intervals and where to find the drain plugs are best looked up in the maintenance handbook that came with your bike, or in the relevant edition of Clymer’s handbooks. A quick read-through may help to order gaskets, if needed, and possibly replacement plugs, if the old ones look like they’ve had it. It’s not uncommon for drain plugs to be uncooperative, or strip, and generally can be a pain in the youknowwhere.

Always consider calling our phone operators, who can take the strain out of the preparations at +499312506116 or send them an e-mail at service@wwag.com   

Let’s get started:

1) Set up your bike on a stand,

eg the Becker minilift, 97-441 and make sure that there’s no weight on your front wheel.

2) Fork oil tends to dribble down

the fork legs, and it’s a good idea to place an oil absorbent mat (81-000) under the front end to avoid a mess in your kitchen. If you want less cleaning up when finished, use the PanAm oil slide to direct the oil to the recipient of your choice.

3) Open the large fork tube plugs

on top of your fork with the correct size wrench, nut or the variable size Knipex plier wrench (very useful). This lets the oil drain much more freely. Open the two (left and right) drain plug screws and let drain the oil. A little patience helps to get out as much of the oil as possible. 

4) If necessary clean or replace

the drain screws with new ones, using new gaskets if appropriate. Tighten to torque specs found in the handbook.

5) Now’s the moment for the new oil.

A funnel and a measuring beaker are your minimum equipment, but the PS oil level adjuster 91-891 is just the perfect tool to have round now. Find the correct quantity in your handbook, and fill each leg nice and slow to avoid spills and air bubbles.

6) Tighten those fork tube plugs again

(check your handbook for correct torque).

7) Time for a thorough check

that the oil only got where it was supposed to go, but not on your tires or brake discs.

All clean?

Bingo. You’re ready for the next pot hole filled summer.

From our experience we’d like to point out the possibility to

give us a call, should you encounter snags in the proceedings.

Our dudes have many thousands of two wheeled miles and countless hours spent wrenching under their belts and are ready to help.

Internet forums full of self declared experts may get you answers as well, but don’t bet the farm on them. When you’re wrenching on equipment your life may depend on, like forks, chassis components, brakes etcetera, get advice you can trust.

Becker Mini-Lift for Big Twin
Becker Mini-Lift for Big Twin
The Becker company manufactures a mini lift for the heavy Big Twins, too. Same sturdy quality, with rollers for easy action and with removable lever for easy stowing.
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PanAm Oil Drain Pan and Containers
PanAm Oil Drain Pan and Containers
This is a combination of drain pan and waste oil container, which should be basic equipment for every workshop or garage. It will make an oil change as easy as pie and environmentally sound.
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Low-Profile Oil Drain Pan and Containers
Low-Profile Oil Drain Pan and Containers
Reduce the mess and cleanup required when changing the fluids on your motorcycle. This king size drain pan is designed specifically for use with motorcycles. The low-profile design fits easily under lowered motorcycles and slips beneath rigid frame bikes even when on the side stand. The 10-quart capacity will capture 2 engine oil changes or the complete drain fluids (engine oil, primary and transmission) from one motorcycle. This drain pan is large enough to catch the oil from the entire length of the primary and is sized to hold and drain an inverted primary cover. It features a raised hardware corral, a filter drain surface and a pressure vent hole to prevent oil burping. The drained waste oil is sealed safely inside the pan with gasketed caps and plugs. Convenient carrying handle simplifies transport to an approved waste oil facility.
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PanAm Oil Pads
PanAm Oil Pads
This oil pad soaks up to 2 l of fluid, i.e. oil, gas, etc. A reinforced top and an anti-slip foil on the bottom side make the PanAm oil pad a useful helper in the workshop, garage or living room.
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PanAm Clean-Funnel
PanAm Clean-Funnel
A good funnel is a must have in any workshop when it’s time for an oil change or a refill. The annoying part of these jobs was to stow away the oil dripping funnel into a dark corner where you would find it a few months later contaminated inside-outside with dust, bugs and other debris. The PanAm funnel puts an end to this problem because it features screw-on caps at the top and bottom which can be removed for action and which keep the inside of your funnel perfectly clean during storage. The flexible spout makes it more versatile as it allows to direct the funnel tip in tight spots.
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Knipex Pliers Wrenches
Knipex Pliers Wrenches
Excellent for gripping, holding, pressing and bending workpieces and for careful installation of components with delicate surfaces. The zero backlash jaw pressure prevents damage to edges. Fast adjustment by pushing a button directly on the workpiece. These pliers replace a complete set of spanners with their parallel jaws, which allow infinitely variable gripping of all widths to the specified maximum size. Screwed connections can be tightened and released quickly by using the ratchet principle. The lever transmission ratio is about 10:1 for strong gripping power.
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PS Fork Oil Level Adjuster
PS Fork Oil Level Adjuster
Allows you to make accurate fluid level adjustments to your fork oil. It is easy to operate and makes this job a snap.
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Colony Special Tools for Early Sportster Forks
Colony Special Tools for Early Sportster Forks
Special pin wrench fo removal and installation of the fork piston rod and spring retainers of early Sportster and Super Glides front ends.
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Jims Fork Leg and Tube Clamp
Jims Fork Leg and Tube Clamp
Use this tool to hold fork legs and tubes for easy hands free servicing or re-building. Mounts in a vise to hold the fork firmly during repair without causing damage to the fork assembly. A rubber pad keeps the tubes from being scratched.
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Jims Driver for Steering Head Cups
Jims Driver for Steering Head Cups
Used to remove and install the steering head bearing race. For best results use the Jims spacer and handle.
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Forkoils
Forkoils
OEM Hydraulic Forks
OEM Hydraulic Forks
Accessories for OEM Hydraulic Forks
Accessories for OEM Hydraulic Forks
Hydraulic Forks Custom
Hydraulic Forks Custom
Fork Tubes
Fork Tubes
Fork Sliders
Fork Sliders
Fork Springs
Fork Springs