Tech Tuesday - Fox Lower Leg Removal And Service
Spending a few minutes to remove and clean the lowers of your Fox fork will not only keep it running smooth, but also act as preventative maintenance for down the road. Today's Tech Tuesday shows you how to drop those lowers and replace the all-important lube oil to keep your fork silky.
Check out the tips and video inside to see how the job is done,
Your Fox fork may feel like a million bucks, but if it's been awhile since you've performed any maintenance than there is a good chance that a little love will have it working even better. This job won't require rebuilding the damper, a repair that some will find intimidating, but only removing the lowers for cleaning and reassembling with new lube oil. How do you know when to get your hands oily? Fox says to slide the lowers off once every 25 hours to inspect the seals and foam rings, but this is also the time to clean everything thoroughly and treat the fork to some new lube oil as well. Riders who spend a lot of time in nasty conditions or doing laps of the bike park will want to do it a little more frequently, but it never hurts to be an eager beaver when it comes to maintenance.
What exactly does that oil in there do? It's pretty simple actually, it acts as lube oil to keep your fork running smooth and active. The oil breaks down over time and loses its ability to lubricate the bushings, but it also gets contaminated from the elements. Small pieces of grime, water from hosing your bike down after a ride, and even tiny bits of rubber from your seals all pollute the oil, with the result being that nasty and thick gray sludge that you're about to pour out of your fork lowers. This sludge can not only have a negative effect on performance, making the fork feel sticky and unresponsive, but can also damage your stanchions in the long run. Think of that nasty oil as sand paper, because that's essentially what it is, with millions of invisible grits slowly working away to scour the finish right off of your stanchion tubes. Doing this repair will not only keep your fork running smooth, but it's also preventative maintenance that can save you money in the long run.
Some pointers before you begin...
• There is a good chance that you're going to make a mess during this job, especially if it is your first go at it. Not only do I recommend wearing gloves and eye protection, but it also doesn't hurt to put down an old towel on the floor to soak up any spills. Be sure to properly dispose of your old oil as well, not by just pouring it down the drain!
• You'll be dealing with some small parts during this job, including the foot nuts and the very small detent ball and spring tucked up in the high-speed compression knob. Don't lose them! Having a small dish or container to put these bits in after removal can save you from spending a lot of time on your hands and knees scouring the floor.
• The video shows me removing the fork from the bike, this makes the job much easier, but isn't 100% compulsory.
• Both foot nuts, 10 mm on the spring side and 15 mm on the damper side, are aluminum. This makes them light, but more fragile than if they were steel. Use the correct size tool (not an adjustable wrench) and take your time so as not to damage them during the repair.
• In the video you'll see that I'm using a rubber mallet to tap the foot studs lose from the lower leg assembly. I can't stress enough to never use a standard hammer for this.
• Once you have the lowers off, take a few minutes to inspect your stanchion tubes to be sure that they don't have any fatal scratches or dings in their finish.
• With your lowers off and the upper assembly in the upright position, stroke the fork's damper rod through its travel. It should take effort to stroke, but move freely and not feel notchy. If it feels as if it momentarily loses damping you'll need to service the cartridge, which we'll cover in a future Tech Tuesday.
• There is no point doing all this work and then not properly cleaning the inside of your lowers before putting them back on. You can use a rag and a long screw driver (just be sure not to scratch the bushings inside the leg), or the long plastic handle of a kitchen utensil, to push the rag in and out of the fork. Spraying some non-corrosive cleaning solvent down the legs will help as well.
• When reassembling take note of the flat surface on the adjuster rod that the low and high-speed adjuster knob's setscrew tighten down onto. Be sure to line this up with each setscrew.
• If either of the foot studs spin when reinstalling the foot nuts, a bit of pressure on the fork can help a lot.
Putting in the correct amount of lube oil is vital in order to have your fork working properly. It's all about volume - too much oil and you won't be able to attain full travel, but you need enough in the lowers to lubricate the bushings. Our 180 mm travel 36 VAN RC2 requires 40ml of lube oil in both the damping and spring side, but it will vary depending on the fork model. Be sure to have a close look at the Fox oil volume chart to determine the correct amount that your fork requires. Fox also recommends using their own special 10 wt. fork oil on models featuring gold Kashima equipped stanchion tubes.
What's needed: 2 mm hex wrench, 10 mm socket, 15 mm socket, rubber mallet, oil pan (an old Tupperware container works great), measuring cup, 7 wt. suspension fluid
Want to keep your Fox fork running smooth? Watch the video:
![photo]()
Need more info or some help? Check out the Fox Racing Shox website to see their service guides.
Have you done this job? Want to add a tip or hint of your own? Put it down below!
Past Tech Tuesdays:
Technical Tuesday #1 - How to change a tube.
Technical Tuesday #2 - How to set up your SRAM rear derailleur
Technical Tuesday #3 - How to remove and install pedals
Technical Tuesday #4 - How To Bleed Your Avid Elixir Brakes
Technical Tuesday #5 - How To Check And Adjust Your Headset
Technical Tuesday #6 - How To Fix A Broken Chain
Technical Tuesday #7 - Tubeless Conversion
Technical Tuesday #8 - Chain Wear
Technical Tuesday #9 - SRAM Shift Cable Replacement
Technical Tuesday #10 - Removing And Installing a Headset
Technical Tuesday #11 - Chain Lube Explained
Technical Tuesday #12 - RockShox Totem and Lyric Mission Control Damper Mod
Technical Tuesday #13 - Shimano XT Crank and Bottom Bracket Installation
Technical Tuesday #14 - Straightening Your Derailleur Hanger
Technical Tuesday #15 - Setting Up Your Front Derailleur
Technical Tuesday #16 - Setting Up Your Cockpit
Technical Tuesday #17 - Suspension Basics
Technical Tuesday #18 - Adjusting The Fox DHX 5.0
Technical Tuesday #19 - Adjusting The RockShox BoXXer World Cup
Technical Tuesday #20 - Servicing Your Fox Float Shock
Technical Tuesday #21 - Wheel Truing Basics
Technical Tuesday #22 - Shimano Brake Pad Replacement
Technical Tuesday #23 - Shimano Brake Bleed
Visit Parktool.com to see their entire lineup of tools and lubes.
Check out the tips and video inside to see how the job is done,
Your Fox fork may feel like a million bucks, but if it's been awhile since you've performed any maintenance than there is a good chance that a little love will have it working even better. This job won't require rebuilding the damper, a repair that some will find intimidating, but only removing the lowers for cleaning and reassembling with new lube oil. How do you know when to get your hands oily? Fox says to slide the lowers off once every 25 hours to inspect the seals and foam rings, but this is also the time to clean everything thoroughly and treat the fork to some new lube oil as well. Riders who spend a lot of time in nasty conditions or doing laps of the bike park will want to do it a little more frequently, but it never hurts to be an eager beaver when it comes to maintenance.
What exactly does that oil in there do? It's pretty simple actually, it acts as lube oil to keep your fork running smooth and active. The oil breaks down over time and loses its ability to lubricate the bushings, but it also gets contaminated from the elements. Small pieces of grime, water from hosing your bike down after a ride, and even tiny bits of rubber from your seals all pollute the oil, with the result being that nasty and thick gray sludge that you're about to pour out of your fork lowers. This sludge can not only have a negative effect on performance, making the fork feel sticky and unresponsive, but can also damage your stanchions in the long run. Think of that nasty oil as sand paper, because that's essentially what it is, with millions of invisible grits slowly working away to scour the finish right off of your stanchion tubes. Doing this repair will not only keep your fork running smooth, but it's also preventative maintenance that can save you money in the long run.
Some pointers before you begin...
• There is a good chance that you're going to make a mess during this job, especially if it is your first go at it. Not only do I recommend wearing gloves and eye protection, but it also doesn't hurt to put down an old towel on the floor to soak up any spills. Be sure to properly dispose of your old oil as well, not by just pouring it down the drain!
• You'll be dealing with some small parts during this job, including the foot nuts and the very small detent ball and spring tucked up in the high-speed compression knob. Don't lose them! Having a small dish or container to put these bits in after removal can save you from spending a lot of time on your hands and knees scouring the floor.
• The video shows me removing the fork from the bike, this makes the job much easier, but isn't 100% compulsory.
• Both foot nuts, 10 mm on the spring side and 15 mm on the damper side, are aluminum. This makes them light, but more fragile than if they were steel. Use the correct size tool (not an adjustable wrench) and take your time so as not to damage them during the repair.
• In the video you'll see that I'm using a rubber mallet to tap the foot studs lose from the lower leg assembly. I can't stress enough to never use a standard hammer for this.
• Once you have the lowers off, take a few minutes to inspect your stanchion tubes to be sure that they don't have any fatal scratches or dings in their finish.
• With your lowers off and the upper assembly in the upright position, stroke the fork's damper rod through its travel. It should take effort to stroke, but move freely and not feel notchy. If it feels as if it momentarily loses damping you'll need to service the cartridge, which we'll cover in a future Tech Tuesday.
• There is no point doing all this work and then not properly cleaning the inside of your lowers before putting them back on. You can use a rag and a long screw driver (just be sure not to scratch the bushings inside the leg), or the long plastic handle of a kitchen utensil, to push the rag in and out of the fork. Spraying some non-corrosive cleaning solvent down the legs will help as well.
• When reassembling take note of the flat surface on the adjuster rod that the low and high-speed adjuster knob's setscrew tighten down onto. Be sure to line this up with each setscrew.
• If either of the foot studs spin when reinstalling the foot nuts, a bit of pressure on the fork can help a lot.
Putting in the correct amount of lube oil is vital in order to have your fork working properly. It's all about volume - too much oil and you won't be able to attain full travel, but you need enough in the lowers to lubricate the bushings. Our 180 mm travel 36 VAN RC2 requires 40ml of lube oil in both the damping and spring side, but it will vary depending on the fork model. Be sure to have a close look at the Fox oil volume chart to determine the correct amount that your fork requires. Fox also recommends using their own special 10 wt. fork oil on models featuring gold Kashima equipped stanchion tubes.
What's needed: 2 mm hex wrench, 10 mm socket, 15 mm socket, rubber mallet, oil pan (an old Tupperware container works great), measuring cup, 7 wt. suspension fluid
While I didn't need to replace the seals on my fork, if you need to, follow the same dis-assembly procedure as stated above in order to remove the lowers. Once the lowers are off you can use an 18 mm open end wrench to pry the seal up and out of its bore, being careful not to score the inner surface of the leg. Don't worry about damaging the seals, you'll be replacing them anyway. Now remove the foam ring that was hidden under the seal. To install the new seals, first slide them up the stanchion tube, not into the fork lowers. This limits that chance of damaging the new seals during installation. After dipping the foam rings in your new oil, slide them up into position under the new seals. Now you can reinstall your lowers, sliding them up onto the stanchion tubes. Use your fingers to seat the new foam rings and seals into the seal bore. If the fit seems tight you can use a socket or another blunt tool on the seal's outer edge to push it in place. Never push on the dust wiper lip unless you want to buy another set of seals.
Need more info or some help? Check out the Fox Racing Shox website to see their service guides.
Have you done this job? Want to add a tip or hint of your own? Put it down below!
Past Tech Tuesdays:
Technical Tuesday #1 - How to change a tube.
Technical Tuesday #2 - How to set up your SRAM rear derailleur
Technical Tuesday #3 - How to remove and install pedals
Technical Tuesday #4 - How To Bleed Your Avid Elixir Brakes
Technical Tuesday #5 - How To Check And Adjust Your Headset
Technical Tuesday #6 - How To Fix A Broken Chain
Technical Tuesday #7 - Tubeless Conversion
Technical Tuesday #8 - Chain Wear
Technical Tuesday #9 - SRAM Shift Cable Replacement
Technical Tuesday #10 - Removing And Installing a Headset
Technical Tuesday #11 - Chain Lube Explained
Technical Tuesday #12 - RockShox Totem and Lyric Mission Control Damper Mod
Technical Tuesday #13 - Shimano XT Crank and Bottom Bracket Installation
Technical Tuesday #14 - Straightening Your Derailleur Hanger
Technical Tuesday #15 - Setting Up Your Front Derailleur
Technical Tuesday #16 - Setting Up Your Cockpit
Technical Tuesday #17 - Suspension Basics
Technical Tuesday #18 - Adjusting The Fox DHX 5.0
Technical Tuesday #19 - Adjusting The RockShox BoXXer World Cup
Technical Tuesday #20 - Servicing Your Fox Float Shock
Technical Tuesday #21 - Wheel Truing Basics
Technical Tuesday #22 - Shimano Brake Pad Replacement
Technical Tuesday #23 - Shimano Brake Bleed
Visit Parktool.com to see their entire lineup of tools and lubes.
Author Info:
Member since Oct 18, 2005
Must Read This Week
[UPDATED] Final Elite XC Results & Overall Standings from the Mairiporã XC World Cup 2024
42106 views
42106 views
Sign Up for the Pinkbike Newsletter - All the Biggest, Most Interesting Stories in your Inbox
PB Newsletter Signup
Well I guess that's the cost of performance. . .
You can see the chart here: service.foxracingshox.com/consumers/Content/Service/oil_volumes.htm
Cheers,
S
one question about my Fox 40 rc2 2010.
is spilling oil from the left leg(spring side). the fork is pretty new , I used it maybe 15 hours. But the bike has been stored hanged on the wall (front tire up) for the last 2 weeks. can this being the problem? what should I do now?
I take it that for the plain-jane 36 Van, w/o the rebound on the bottom that I can just remove the two footnuts and slide the lowers off?
Grant
1.If you are a brute force guy with a poor "technical culture" do not service your forks, or at least do not reassemble them yourself! Some people are like that - accept that before you loose lots of money.
2.If you have never took a CERTAIN fork apart, always ask for guidelines someone trusted who did (i.e a bike mechanic)
3.NEVER OVERTIGHTEN! All parts in forks do not require high torque, they will never get loose.
Thanks
Which leads me to my main point. Echoing Waki, be extra careful to the torque you are using on those footnuts, as overtorquing them can damage the rods they screw onto, which are part of the rebound cartridge assembly in the right leg, and the spring assembly in the left leg. They are VERY expensive to replace.
I did this last summer after the shop told me to just screw the footnuts "good and snug". I guess I erred on the side of caution (didn't use a torque wrench), and paid the price. I had to buy a new rebound assembly for close to $400 (for the RC2). In speaking to many mechanics about this issue (including the former Fox Warranty guy for Western NA), this is not an uncommon occurence, even for experienced pro mechanics.
So, my point is, pay VERY close attention to the torque specs of the footnuts. VERY close attention...
Don't put any blue on the foot nuts. Both the nuts and the studs are aluminum and don't require and thread locking compound. You are better off to put a small dab of grease and torque them both to the proper spec, that being 50 in/lbs. It isn't the end of the world If you don't have a torque wrench, just use common sense. Think of it this way: 50 in/lbs means that the torque required is 50 lbs on a 1" handle, which is bit weird to relate to.. but if you do the conversion you'll find that it is just a hair over 4 lbs of force on a foot long tool, which is a bit easier to think about. Don't over do it!
How about the bushings? Do you know what the tell tales signs of wear in them are and how long they should last before I should get a shop to check them out?
service.foxracingshox.com/consumers/index.htm#service/forks/40/40rc2.htm
It mentions that the F-Series forks can NOT be increased to 120mm of travel. However the 831 is neither and looking at the FOX site it mentions that the fork's travel is internal adjustable to 120mm of travel so you should be fine, still you should check with FOX before going ahead.
The process should be very similar if not the same as the FLOAT/F-Series procedure.
Marzocchi is actually the trickiest to rebuild as they are open bath, but still with a bit of patience really not that bad.
please vote me santa2011.ru/?p=645 .... Click the green plus =) thanks in advance)