Fork oil

dirty steeler trick

steeler gave me wrong info. it's about $5 for 1/2 a litter

I asked a local indy what they recommended for my WG forks, he gave me a qt of 10W40. Anyone heard of this?

Next someone will say you can use Syn3 in all 5 holes!

Joe

I can see no logical reason to use a multi-viscosity oil. I just had my seals replaced by an Indy and I asked what they used. (Sportster) They told me straight 20W and that's what I had them put in. I had put straight 30W in before and I liked the stiffer ride, but to be honest I can't tell that much difference between the two.

Multi-vis? Synthetic? My opionin? Don't waste your hard-earned dollars!:gah:

So From What I'm Gathering From Every One Is, If You Want To Change Out Your Fork Oil You Don't Have To Use The Standard ( Fork Oil) You Can Put In 15,20,30 Wt Motor Oil. Or Transmission Fluid, And Hydralic Fluid. Didn't Read Any Body Say'n How Often You Should Change It Out. Or If Any One Has A Link For A Chart For How Many Oz. For Fork Size, Would Be Easy For Stock Aplications, But As For Me Going From Stock To 41mm 8" Over, The Manual Is No Good. Just Wondering, So If I Need To Do It.

My manual says once per year. I think mileage would be a better indicator and probably every 10-12K maybe?

I was wondering what those looong raked things were on your front end. Whoever sells them should be able to tell you, OR if all else fails:

Calculate the total area of a stock fork, not worying about the parts inside etc. and check what the manual says. I can get that for you if you want. Then calculate the same total area of your forks and determine the ratio difference.

For example, if the stock tube is 100 CI total and it required 9 OZ, and yours are (for sake of simplicity) 200CI, you would probably need 18 oz.

Simple math for close enough to calculate area is:
.785 X D sq. X Length = Area in Cubic Inches.

(231 CI = 1 US gallon by the way).

PM me with the length of the main tube that holds the oil and the diameter, and I'll measure mine and see what the book says and send you the numbers if you want. Measure the OD if you want. We are looking for a ratio and not being exact, so even if the calculation is flawed, they both will be flawed in the same way so it doesn't really matter. We are still comparing apples to apples.

41mm Tubes@24.5 To Lower Legs, Lower Legs Are 64mm @16.5, Total Length Of Forks 41 Inches.

For this exercise I'm calculating only the area of the lowers

My stock lowers are 44mm (1.73") X 14" Long. Total area = 32.7 CI

Your lowers are 64mm (2.52") X 16.5" Long. Total area = 82.17 CI

82.17/32.17 = 2.6 So yours theoretically take 2.6 x's as much oil as mine.

My specs call for 9 fluid oz in a "WET" fork, or 10.2 fluid oz in a "DRY" fork.
"Wet" is when you just drain and refill - "Dry" is when you do a complete disassembly.

SO, if mine take 9 FL OZ "WET", yours take 2.6 x's as much, or 23.4 FL OZ "WET", and 26.52 FL OZ "DRY".

Again, I used some shortcuts on the area and if somebody want's to be exact they may come up with something different. This should get you pretty close.

By the same token I disavowel all I've posted if you use this data and and it's wrong.
:roflmao:

in my dyna repair manual it says that you can use a oz/cc amount or measure down from top of tube to oul, with spring removed and fork compressed. the fxdwg use 12 oz or 7.28 inches, if you use a longer tube i think you should use the 7.28 measure, that way you would have the right amount of air to load the shock. if you know how your fork measurement before extension, then after the extension set to same measurement. that should be right. i havn't done mine yet because on my fxdx i have to dissasemble the forks to change oil. it shows a few special tools to do it. the forks have a preload adjustment as well as a compression and rebound adjustment. they don't have a drain plug, and pulling the top cap is more than just unscrewing it. the maintanance schedule says change every 20,000 miles.

That's Kinda Like Mine, Don't See Any Drain Hole's, Looks To Me Like The Only Way To Take Out And Put In Oil Is Through The End Cap. The Forks Came Pre-assembled, So I'm Clueless, So For This The Hole Front End Has To Come Off, Not To Mention The Top Tree Covers The Fork Tube Cap.

i'm up against the same thing. seems that the manual is only good for stock situations:witsend:

I wonder if you could drill and tap a hole at the bottom of the fork tubes and put in a threaded drain plug while you have them apart. If they make one with a check valve in it that would really be cool that way you could drain the oil and pump the refill in through the bottom, there must be an easier way then having to disassemble the whole works. Al

There should be one on the very bottom unless those are some big hurken aftermarket forks you got. In that case, ????

It's about a 1/4" hex regular machine capscrew with copper washer for a seal. If you pull it out, be sure to either replace the copper seal or heat it to soften it since copper "work hardens".

It is reference number 18 in the H-D 95-96 Sportster service manual. Oh that's right, I don't think you have one.:roflmao: Part number is 45405-75A (Capscrew and washer set - need 2)

Even with the drains open, the top caps have to come off otherwise it creates a vacuum and it would have to sit for 765 hours and 14 minutes to drain probably. BE CAREFUL! Top cap under extreme spring tension. My first cap flew up and hit my garage ceiling. Glad I wasn't looking at it!

It took two of us to get them back on. One to push down with all his might and one to turn the socket wrench!:gah:

What a PITA, seems like a fork cap with a removable Plug which would allow it to vent would be a good idea too, some enterprising fabricator might even find a market for it. That way your could drain the oil, measure it and fill from the top leaving the springs in place, or am I missing something??? AL

Well Now That I Have Looked, There Is A Hole On The Very Bottom, About A 1/2" One, Gives A Good View Of The Axle Bolt, Maybe The Hole Goes Further And There Is A Plug Behind It, But I'm Not Take'n That Front Tire Off Just To See, It's A Pain In The But To Get That Bolt Threaded. Still That Would Only Be A Exit, Would Prob. Still Have To Pull The Caps Off To Get The Oil In. Even If There Was A Plug Behind The Axle, That Would Be About A 2,3" Drain Flow Till It Got To The End, Guess Well Never Know Till I Do It.

No. I had a similar thought and the next time the caps are off, I'm drilling and tapping for a 1/4" NPT thread and use a female hex plug (chrome of course or stainless) so it doesn't protrude above the cap. Should be easy enough. Idea is free to all members!

After you open the drain screws and remove a cap, (or my NPT plug) you still have dry hump the forks up and down a bunch and a half times to get the oil out too.