Fork Oil Change Made Easier

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PapaUtah

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I am getting ready to change the fork oil in the Metallic Monster again...I thought I would share my homebrew fork oil level setter I fashioned out of leftovers laying around the garage. My Gen 3 required different levels in each leg. I have marked the appropriate levels by filing a small groove in the outer copper tube in case my sharpie markings fade away. Simply move the bottom collar to the proper height and then bring the polycarbonate plate and upper collar down and locked as a stop. I have a large syringe I then use to evacuate the oil in the fork tube down to the proper level. Gets the level as close as anything I could possibly do. Has worked well on the annual changes on my old 05 and the first change (soon to be second) on my 13.

IMAG0086_zpszdwyf2fy.jpg


 
I love the ingenuity of folk, and it saves giving more money to Motion Pro.

There is another aspect too. Making your own jigs and fixtures forces you to understand why things are the way they are. It helps develop a deeper understanding of the job in hand and probably makes you a better rider.

Now ... where is the automatic model that makes coffee while it changes the oil?

 
I love the ingenuity of folk, and it saves giving more money to Motion Pro.
There is another aspect too. Making your own jigs and fixtures forces you to understand why things are the way they are. It helps develop a deeper understanding of the job in hand and probably makes you a better rider.

Now ... where is the automatic model that makes coffee brews beer while it changes the oil?
Fixed it for ya.

 
Do you suck the old oil out with a large syringe or are you pulling the fork tubes once a year? Probably a dumb question but the last bike I changed fork oil on had drain screws on the bottom and didn't require removal of the tubes.

 
Do you suck the old oil out with a large syringe or are you pulling the fork tubes once a year? Probably a dumb question but the last bike I changed fork oil on had drain screws on the bottom and didn't require removal of the tubes.
You drain the oil normally. That device lets you set the oil level accurately after you have re-filled them.

 
A very innovative solution and I'll be happy to copy your idea. Is changing the fork oil so often really necessary, or is it just your personal preference?

 
Do you suck the old oil out with a large syringe or are you pulling the fork tubes once a year? Probably a dumb question but the last bike I changed fork oil on had drain screws on the bottom and didn't require removal of the tubes.
You drain the oil normally. That device lets you set the oil level accurately after you have re-filled them.
Thanks, that's what I was afraid of. I was hoping that there was an easier way to drain the fork oil than spending hours pulling the whole front of the bike apart. Remember the old days when you would just remove a drain screw at the bottom of each tube, pump the forks a few times, replace the screw , fill the forks and you're done.

 
Thanks, that's what I was afraid of. I was hoping that there was an easier way to drain the fork oil than spending hours pulling the whole front of the bike apart. Remember the old days when you would just remove a drain screw at the bottom of each tube, pump the forks a few times, replace the screw , fill the forks and you're done.
Don't be discouraged- the forks can removed without "spending hours pulling the whole front of the bike apart". Front fender off, front wheel off, remove the forks. Takes patience but I've done it twice without removing any other components. The whole job start to finish can take as little as 3 hrs without getting in any hurry at all.

 
worth the trouble to pull the forks so they can be turned upside down. this gets all the grey mung out that is usually below the level of drain screws on forks that have them. I use kerosene or cheap tranny fluid to flush them and then hang them upside down to drain...

 
I change the fork oil every winter/spring. Flush it with the leftovers from last years can of fork oil. When its back to clear its clean. After a year around here the old stuff is usually a dark gray. I am sure if I let it go longer I would end up with a black mixture coming out. I only am able to put on about 12K a year or so in the short riding season in the northland.

I have a large syringe I attach to the clear tubing...overfill the tubes then just suck out the overfill with the syringe. Has worked like a charm on the new 13. On my 05 I could just set it and forget it. Same height in each tube. Had to add the markings for left/right for the Gen 3. I have been lucky so far, haven't replaced a bushing in my Gen 3 or Gen 1. I clean the seals, polish the tube and try to keep the splooge off tubes and I haven't experienced a leak, clank, stiction, etc. with either bike. I am sure my luck will end sometime.

 
That's a nice fab job on the tool. I still use a bent piece of wire to show me the level to fill to. Still have a Motion Pro tool that was a gift that I've never unwrapped.

To me it's not really a "change" unless the fork is pulled to get all of the old oil out. YMMV.

 
I was thinking of changing the fork oil on my '13 at an upcoming tech day, as no one there has done it that I know of, is there a link, or thread, that shows all the steps in doing this? I've done some searching on here, but all I can seem to find is discussion about it, but not the details of how to do it. Thanks.

 
I'll say the Gen IIIA's aren't much different than any prior Gen2, so you can follow those directions. The upside down ES forks will have their own procedure.

PS - Traxxion sells a fork oil setting tool with a syringe....... cheaper on ebay rather than directly from them.

 
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This is the process for the Gen I and II, and I can't see anything changing for the GEN III - but PLEASE somebody correct me if I'm wrong:

Bike on the center stand. It's not necessary, but if you have a hydraulic jack under the exhaust or similar to raise the front wheel up a couple inches, it helps.

Take note of its setting and loosen the pre-load on each fork all the way out.

Cover the tank with something to protect it.

Do one fork at a time.

Loosen the upper triple clamp bolt.

Hold the handlebars and loosen the fork caps carefully. You will need a long wrench to do this - be AWARE of the possibility of damaging your tank paint with the wrench - be CAREFUL.

Note where each fork sits within the triple clamp for re-assembly (the line between the cap and the upper fork tube should be JUST above the top of the triple clamp).

Remove the front wheel

Remove the front fender

Sit down in front of the bike. Take aim where the fork could fall to the ground (if you weren't holding it with one hand). Place a towel or something padded there. If the fork surprises you and falls to the slab, you will be pissed at yourself (DAMHIK). Wile holding the fork with one hand, loosen the lower triple clamp bolt. When the fork begins to slide out, grab it with the other hand.

Place the fork tube on top of an old towel or rag. Get a pan or something to catch the old oil.

Remove the loosened fork cap. The spring will have some pressure on it, but it won't go flying to the ceiling or poke your eye out. Remove the washer, the pre-load spacer, and the fork spring. Place these on a towel on your bench in the order they are assembled so you don't get confused. NOTE - do one fork at a time.

Turn the fork upside down and exercise it back and forth a few times to evacuate all of the old oil. Take a deep breath. That stench you are smelling is your old burnt fork oil mixed with bug feces and road dirt and it's gotta go!

Turn the fork upright, and add 2-4 ounces of ATF or similar. Exercise the fork up and down to allow the ATF to slosh around and remove the "mung" lodged in the bottom of the fork. You are using the ATF (which is actually hydraulic oil) as a solvent to remove and dissolve the muck out of your forks.

Turn the fork upside down and evacuate the ATF. Repeat this process several times until the ATF comes out clean. Then use a small amount of fork oil to provide a final rinse - to rinse out the film of ATF still inside the fork.

Fill the fork to the required level. The OP's method is as good as I've seen. I suppose in the absence of a large syringe, one could use a hand held vacuum pump for the same purpose.

Examine the upper fork tube - the part that slides in the fork seal (the range of your suspension). Wipe off any grit, dirt, sludge. Use a very small screwdriver and carefully pull the dust seal away from the fork and remove any grit that you find there.

Reverse the assembly process.


We need two things:
1. The required level for each leg (from the top of the upper fork tube.
2. Torque specs for the triple clamp bolts and the fork cap. Torque specs for the front wheel dis-assembly are in the Bin-o-facts.

Cheers!

 
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Pants, you're da' Man! :)

A few questions.

*No special tools, right?

*How much fluid total would I need, and...where would I get info for fluid level for each fork?

*I take it centerstand needs to be on 2x6 or similar?

* I've seen different weights mentioned (5 & 10wt), advantages to either?

Thanks again for the help.

 
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