[Optimax150]

Just received my new 2012 fox 40. I'm about 180 or a bit less now, stock spring. First time I sat on the bike the fork barely sank into its travel. Small bumps are harsh and on the first hard hit, a small jump, heard a high pitched squeak.
I heard the these forks need breaking in time. That would affect the small bump but what about the sag? Doing some research on the Internet I found that fox had a tendency to ship forks low on oil and dry seals. I found you can pry up the seals on the lowers and lube them up along with the foam seals. But I also read you don't want to do that with the skf seals, anybody done this on there 2012 40? Got a feeling I'm going to open the fork up and look at the oil levels and lube the seals.

 

[Udi]

They need time to break in, probably a solid week of chairlift riding or the equivalent.

If you are checking/changing oil level in the lowers it's well worth using the Fox 'Green' 10wt designed for the purpose, in my experience nothing works quite as well. I haven't seen any coming without the correct oil quantities, but the spring grease can absorb a little just like any other fork. Don't pry them up either.

 

[tabletop84]

Use enginge/transmission oil for the lowers. Works better for lubrication purposes than any fork oil. I don't know if the 40 has an upper and lower seal but for Rock Shox and Marzocchi replacing the foamrings with a good amount of thin grease adds suppleness.

 

[HardtailHack]

Use enginge/transmission oil for the lowers. Works better for lubrication purposes than any fork oil. I don't know if the 40 has an upper and lower seal but for Rock Shox and Marzocchi replacing the foamrings with a good amount of thin grease adds suppleness.

I really don't understand peoples love for doing this, why would you want a high viscosity high shear strength oil in your lowers? People say it has better clingability, why do you need that?
If your seals are flogged oil pours out, that means oil from the lowers is getting to the bushings, fork oil is designed for forks car oil is designed for cars, keep it that way.

Sorry to be so negative.

 

[Udi]

Use enginge/transmission oil for the lowers. Works better for lubrication purposes than any fork oil. I don't know if the 40 has an upper and lower seal but for Rock Shox and Marzocchi replacing the foamrings with a good amount of thin grease adds suppleness.

Please don't do any of the above.

The lubrication system in the Fox fork is very different to other brands - primarily because they have always used a slotted upper bushing rather than only the slotted lower in most other forks, and the purpose of the foam ring is to catch the oil as it squirts up (through both sets of bushings) and thus dynamically lube the upper bushing upon each compression. RS Boxxer and Marzocchi 888 forks both use separate pressure seals, so there is no way to constantly soak a foam ring placed below the wiper seal - and thus on these forks a foam ring is pointless. The Fox however is different and the foam ring is an important part of the lubrication system's operation.

For lubrication oil, "engine/transmission oil" is an incredibly vague suggestion (given the number of brands, models, and viscosities of oils available), and a dangerous one because most of these products include a huge variety of additives (VI modifiers, extreme pressure additives, friction modifiers) that may or may not cause harm to bushings - including swelling of their polymer coating which I have seen first hand with some oils. Just because the oil you picked worked fine in your product, doesn't mean it's applicable universally.

The genuine 'Green' oil on the other hand I've tested back to back with multiple other fluids and noticed an improvement in sliding performance, and as with any OEM fluid for a given fork, no negative effects in the long term.

 

[HardtailHack]

Actually tabletop might be on to something, if use engine oil in my lowers when my seals start leaking I can just throw a bit of seal swelling additive in and I'm good to go for another year.

 

[iRider]

The genuine 'Green' oil on the other hand I've tested back to back with multiple other fluids and noticed an improvement in sliding performance, and as with any OEM fluid for a given fork, no negative effects in the long term.

Did you also test this on other forks, say Boxxer, and did it work?

 

[tabletop84]

I really don't understand peoples love for doing this, why would you want a high viscosity high shear strength oil in your lowers? People say it has better clingability, why do you need that?
If your seals are flogged oil pours out, that means oil from the lowers is getting to the bushings, fork oil is designed for forks car oil is designed for cars, keep it that way.

Sorry to be so negative.

For lubrication oil, "engine/transmission oil" is an incredibly vague suggestion (given the number of brands, models, and viscosities of oils available), and a dangerous one because most of these products include a huge variety of additives (VI modifiers, extreme pressure additives, friction modifiers) that may or may not cause harm to bushings - including swelling of their polymer coating which I have seen first hand with some oils. Just because the oil you picked worked fine in your product, doesn't mean it's applicable universally.

The genuine 'Green' oil on the other hand I've tested back to back with multiple other fluids and noticed an improvement in sliding performance, and as with any OEM fluid for a given fork, no negative effects in the long term.

Sorry guys but if you knew what you are talking about then you would know that fork oil is developed with the focus on damping consistency whereas motor oil has superiour lubrification capabilities. That's a fact. The additives in motor oil won't harm your bushings. I and many other guys (just search on mtb-news.de fro 'motoröl') are using this for years now and I never heard andything negative about it.

As for the foamring replacement I already stated that it's only recommendable if there are two seals with the foamring in between like in most rs and mz forks.

P.s. please don't use engine oil on the damping leg of an open bath fork for obvious reasons.

 

[nowlan]

When I maintain something I paid over 2 grand for, I generally use the recommended products to do so from that company.

 

[Brian HCM#1]

Did you check the compression settings? I just got mine back from service and the compression was just about max.

 

[yd35]

I think it's worth opening it up and checking the oil levels along with lubing the foam rings. I have a 2012 40, and one of the legs came a little short on oil.

Most likely, you just need to break the fork in. It's definitely harsh out of the box, and you'll have that aha moment when everything clicks. I think it took about a week for me to reach fork nirvana.

 

[tacubaya]

I've done a lot of testing with different lubricants for splash bath and Fox green is one of the best oils you can use. Right now I'm testing Maxima Maxum Ultra4 which the SRAM WC technicians use. It requires a bit more of testing than other oils because being an ester based oil I want to make sure their seal neutrality is spot on.

 

[tabletop84]

I have no personal experience with but a few guys at mtb-news say that guiding-ways oil is bet as a fork lubricant. Not sure if the translations is correct.

I'm talking about oil that is used in this context:

 

[tacubaya]

I have no personal experience with but a few guys at mtb-news say that guiding-ways oil is bet as a fork lubricant. Not sure if the translations is correct.

I'm talking about oil that is used in this context:

I've tested way oil, specifically Mobil Vactra 2.

 

[tabletop84]

http://www.peterverdone.com/archive/bikesuspension.htm

engine oil -> lubrification

hydraulic /fork oil -> damping

You can't create one oil who stays in the same consistency over various temperature ranges without creating bubbles and make it lubrificate well. Fork oil is usually to thin to create a consistent oil film.

In a closed cartridge damper system it's therefore always better to use oil that was created with the focus on lubrification not damping oil. Get it?

 

[tacubaya]

http://www.peterverdone.com/archive/bikesuspension.htm

engine oil -> lubrification

hydraulic /fork oil -> damping

You can't create one oil who stays in the same consistency over various temperature ranges without creating bubbles and make it lubrificate well. Fork oil is usually to thin to create a consistent oil film.

In a closed cartridge damper system it's therefore always better to use oil that was created with the focus on lubrification not damping oil. Get it?

Or say fvck it and try everything until you find something awesome...



... which is what I'm doing.

 

[Udi]

As for the foamring replacement I already stated that it's only recommendable if there are two seals with the foamring in between like in most rs and mz forks.

This thread is clearly about a 2012 Fox 40.

Sorry guys but if you knew what you are talking about then you would know that fork oil is developed with the focus on damping consistency whereas motor oil has superiour lubrification capabilities. That's a fact. The additives in motor oil won't harm your bushings. I and many other guys (just search on mtb-news.de fro 'motoröl') are using this for years now and I never heard andything negative about it.

The Fox "Green" oil was actually developed specifically for bushing lubrication purposes, it's a custom formulation made for Fox by (I believe) Torco - but it's not part of their regular product lineup. Its secondary purpose is as a damper oil in Fox open bath forks, but it is not used as damper fluid in their flagship FIT forks - thus is not primarily a damper fluid. Tacubaya has tried the product back to back with many other oils including non-suspension products and seems to rate it (as have I) - you clearly haven't.

Motor oil does not have 'superior lubrication capabilities' and your suggestion that 'additives in motor oil won't harm your bushings' covers a very broad scope of chemistry. Do you actually know each possible additive in each brand of 'engine/transmission oil', and have you tested each in a lab to know that it will not affect the bushings of this fork in the long term?

engine oil -> lubrification
hydraulic /fork oil -> damping
You can't create one oil who stays in the same consistency over various temperature ranges without creating bubbles and make it lubrificate well. Fork oil is usually to thin to create a consistent oil film.
In a closed cartridge damper system it's therefore always better to use oil that was created with the focus on lubrification not damping oil. Get it?

Again, not correct. An engine/transmission oil is designed to do a myriad of different things, and thus lubrication is definitely not its only purpose. You suggested both of these oil types earlier, but they have a vastly different additive set to each other. Gear oils contain extreme pressure additives to reduce tooth contact wear, and both oils contain VI modifiers to reduce heat-related viscosity change (especially in engine oils). On top of that there are zinc and other metal additives to reduce wear on metal parts, friction modifiers (synchromesh gearboxes require a certain amount of friction to work), and a myriad of other things that do not need to be in a suspension fluid.

Some browsing here (and on their forums) might open your eyes as to how many additives may exist in an engine oil. It's easy to forget that suspension fluid is lubricating a polymer-coated bushing interface, thus somewhat different from engine or gearbox lubricating requirements.

I suggest that people use the recommended fluids for lower lubrication, especially when there is a purpose-made product available. Of course it's fun to experiment and I've tried various motor and gearbox oils in the past, as well as various suspension fluids, but (surprise surprise) the product made for the purpose is what works best.

 

[tabletop84]

Well, that's nice and all but there are more than a few hundred guys on mtb-news that all state that motor oil works far better than any damping oil. Maybe than labeled stuff from fox is on par but as every fox product it's way overpriced for it's performance.

I bet you couldn't tell if motor oil or hat green stuf is in your lowers.

 

[Transcend]

Well, that's nice and all but there are more than a few hundred guys on mtb-news that all state that motor oil works far better than any damping oil. Maybe than labeled stuff from fox is on par but as every fox product it's way overpriced for it's performance.

I bet you couldn't tell if motor oil or hat green stuf is in your lowers.

So a few hundred forum knobs are better than the science used to create said products? Dreams are free, mate. Forum 'tards also claimed for ages that you need to go up 50# in spring weight when you use a Ti spring.

 

[Udi]

Well, that's nice and all but there are more than a few hundred guys on mtb-news that all state that motor oil works far better than any damping oil. Maybe than labeled stuff from fox is on par but as every fox product it's way overpriced for it's performance.

I bet you couldn't tell if motor oil or hat green stuf is in your lowers.

You're missing the point - 'motor oil' could mean anything, you're throwing a blanket statement that they are all the same when there are vast differences. Even if one 'worked' (which as Transcend suggested could mean anything), doesn't mean that another one will.

I've tested the Green back to back with various motor oils as well as various suspension fluids in both RS and Fox lowers and noticed an improvement. I receive nothing from the sales of branded oils, but I'd rather spend the extra for the right product - especially if I'd just spent $1600+ on a new fork.

 

[Optimax150]

Ive been hearing the debate of motor oil and ATF vs fork company oil. The motor oil and ATF sounds like the easiest way to go for me. But I been hearing mixed reveiws about motor oils and ATF. To save me time and hassel in the future I'm going to order the fox green oil. I want to take care of it with the proper oil, not oil that will eat at the bushings or seals even though it might take a while for the oil to do that. Also I've heard nothing but good things about the green oil. I think I can afford a little more to get the proper oil for my fork that I just paid a little over a grand for.
I won't py up the seals, I think that's the pre-skf seal standard.
I'm going to order the oil. While I'm waiting for the oil, I'm going to remove the lowers and check out the seals for lube.

 

[Udi]

Yeah good choices all round.
Considering you only use 50-60ml per leg each service, 1L lasts a long time anyway. When you remove the lowers you can probably catch and re-use the old stuff if there's enough of it while you wait for the new stuff. Doesn't hurt to wipe any excess grease off the spring too. Fox recommend using the same stuff to soak the foam rings and lube the inside of the seals too which has worked for me so far.

Also the stock spring is MUCH firmer than an 888 if that's what you came off, so do keep that in mind if it's still harsh after break in. The blue one sits between a marz firm and x-firm in rate, so you could always try the purple one if needed.

 

[Optimax150]

Yeah I am coming off a 888. That was my first thought to go a lighter spring. My fork was a OE, so no extra springs, I know the regular fork comes with extra springs. The stock spring is ti, but is the extra springs ti or steel? I didnt think I was going to need a softer spring, with me being in the upper range of the stock spring. I do feel I could get away with a lighter spring and add more compression. As of now everything is full open, try to get the fork moving more to help break it in faster.

 

[Udi]

The extras are steel, and it sounds like the stock ti is correct for you anyway - but by that logic the 888 would have been too soft for you if you ran the stock spring in it. Maybe just something to be aware of if you feel it is too firm after it breaks in. Give it plenty of riding time though.

OE = Non kashima? Or did you score a kashima one?

 

[canadmos]

Forget the oil and breaking it in, did you try to adjust the compression settings?

 

[Steve M]

Well, that's nice and all but there are more than a few hundred guys on mtb-news that all state that motor oil works far better than any damping oil. Maybe than labeled stuff from fox is on par but as every fox product it's way overpriced for it's performance.

I bet you couldn't tell if motor oil or hat green stuf is in your lowers.

Fox's 10wt Green oil is not DAMPING oil, it is a lubricant first and foremost. Fox have two "10wt" oils that they use in their products, the 10wt Green (Torco custom blend of some description) and the 10wt Red (Silkolene Pro RSF, 47.36cSt @ 40C from memory). The Red fluid has a particularly high VI, making it very stable across a range of temperatures, which is a great quality to have for consistent damping in sealed cartridge. Red 10wt is their damping fluid.

However, lubricity (how much a lubricant actually reduces friction) can't be directly measured - there is no number or unit of measure for it (right now at least), however it is clearly obvious that different fluids have different capacity for the reduction of friction. The Fox 10wt Green, whilst suitable for their "lower end" dampers (the open bath ones as opposed to the sealed FIT cartridges), is specifically used for its high lubricity rather than its high thermal stability (VI). As Udi pointed out, there are dozens of types of "motor oils" out there with different purposes and capabilities - while some of these may be great, some of them are also terrible for this job. Generalising like that is pointless when the fine details are all that matter.

 

[tuumbaq]

First time I sat on the bike the fork barely sank into its travel.

Which is a normal thing btw...Not saying this is what your problem is but Im surprise no one mentioned this yet.Perhaps you already know this but in case you dont , you measure sag in the attack position (or standing on the bike) not sitting.@180 with the blue spring , the fork should be quite soft actually.Whats your compression settings? have you experiment with different settings at all?The 40 has a LOT of compression and too much of it would definitely feel very harsh.Do you store your bike upside down or at the very least with the front wheel up (vertical)?Keeping both wheels on the ground would prevent the oil from making its way up to the foam rings.Normally by simply riding the thing, oil gets splash all over but after sitting in a box for a few months on a shelf , they tends to get dry.

Starts from the basics first if you havent done it already :

Flip upside down ( try cycling the fork a few times to help the oil migrate down past the bushings)
Dial in the compression
Measure Sag

THEN try lubing it with proper oil if it doesnt improve.( and yes the Fox green oil does make a noticeable difference in performance)

 

[canadmos]

Should also be noted, how slack is your head tube angle? I found my bike in the really slack position didn't offer very good feedback and lacked sensitivity while riding around on relatively flat ground. It wasn't until the speeds and slope of the trail increased that the fork came alive. I also had to set it up a bit softer in the very slack setting.

Have you ridden it yet beyond the parking lot test?

 

[Optimax150]

The extras are steel, and it sounds like the stock ti is correct for you anyway - but by that logic the 888 would have been too soft for you if you ran the stock spring in it. Maybe just something to be aware of if you feel it is too firm after it breaks in. Give it plenty of riding time though.

OE = Non kashima? Or did you score a kashima one?

I got the kashima one. I will give this spring plenty of ride time before I make a switch.

 

[Optimax150]

Forget the oil and breaking it in, did you try to adjust the compression settings?

As stated in above post, I'm running with everything open, minus rebound.

 

[Optimax150]

Which is a normal thing btw...Not saying this is what your problem is but Im surprise no one mentioned this yet.Perhaps you already know this but in case you dont , you measure sag in the attack position (or standing on the bike) not sitting.@180 with the blue spring , the fork should be quite soft actually.Whats your compression settings? have you experiment with different settings at all?The 40 has a LOT of compression and too much of it would definitely feel very harsh.Do you store your bike upside down or at the very least with the front wheel up (vertical)?Keeping both wheels on the ground would prevent the oil from making its way up to the foam rings.Normally by simply riding the thing, oil gets splash all over but after sitting in a box for a few months on a shelf , they tends to get dry.

Starts from the basics first if you havent done it already :

Flip upside down ( try cycling the fork a few times to help the oil migrate down past the bushings)
Dial in the compression
Measure Sag

THEN try lubing it with proper oil if it doesnt improve.( and yes the Fox green oil does make a noticeable difference in performance)

Sorry should've stated that better, I was standing on the bike.
I did notice the fork got a little better when I flipped the bike, as I was getting suited up to ride.
I do notice the compression range is pretty big.
I think everything just got dry. I got it from go-ride and it probaly been on there shelf for a while.
I'm already have the green oil ordered for future use. Thanks for the pointers.

 

[Optimax150]

Should also be noted, how slack is your head tube angle? I found my bike in the really slack position didn't offer very good feedback and lacked sensitivity while riding around on relatively flat ground. It wasn't until the speeds and slope of the trail increased that the fork came alive. I also had to set it up a bit softer in the very slack setting.

Have you ridden it yet beyond the parking lot test?

Yes I have ridden it on the trail. I already know its going to be a little harsh on the trail due to the fork not being broken yet.
Total ride time so far on the fork, two rides.

 

[buckoW]

If you have the compression totally open and it still feels firm with a blue spring then I think you should try a purple one so you can run some compression to control the ride a little. Maybe later switch back to a blue spring when you get up to speed and start running out of a useable adjustable range of compression.

The green oil is definitely better, btw.

 

[dilzy]

I've done a lot of testing with different lubricants for splash bath and Fox green is one of the best oils you can use. Right now I'm testing Maxima Maxum Ultra4 which the SRAM WC technicians use. It requires a bit more of testing than other oils because being an ester based oil I want to make sure their seal neutrality is spot on.

Your actually using a full synthetic ester oil for lower lubrication? Can I have your scrooge mcduck piles of money you waste on high temp engine oils?

 

[tabletop84]

So a few hundred forum knobs are better than the science used to create said products?

Haha, yeah rocket science. It's just pointless to use damping oil in lowers. Period.

You're missing the point - 'motor oil' could mean anything, you're throwing a blanket statement that they are all the same when there are vast differences. Even if one 'worked' (which as Transcend suggested could mean anything), doesn't mean that another one will.

I've tested the Green back to back with various motor oils as well as various suspension fluids in both RS and Fox lowers and noticed an improvement. I receive nothing from the sales of branded oils, but I'd rather spend the extra for the right product - especially if I'd just spent $1600+ on a new fork.

Most mineral based motor oils work better than any damping oil 10w40, 15W40...

 

[Udi]

Haha, yeah rocket science. It's just pointless to use damping oil in lowers. Period. Most mineral based motor oils work better than any damping oil 10w40, 15W40...

Multiple people have already pointed out that the recommended oil is not a damper oil, and rather primarily designed as a lubrication oil. No one suggested using a damper oil, you just made that assumption. Saying 'most mineral based motor oils' is just as vague as your original suggestions, different brands and models of oils use different additive packages.

In fact, even a 10w40 and 15w40 in the exact same brand and model of oil can use vastly different chemistry and additive packages.

It's so much easier to just spend the extra few dollars and use the product that has been specifically made for the purpose.

 

[Udi]

Did you also test this on other forks, say Boxxer, and did it work?

I did in a friend's Boxxer, and it worked very well, however I only tested short term - haven't heard any complaints yet. I think tacubaya here also did the same and had a similar experience but maybe he can comment himself.

 

[HardtailHack]

This may sound stupid, but I had my Totem for ages and it always felt horrible and one day a friend wound all my dials to full. I knew something wasn't right but did a couple of runs with everything set to max compression and rebound for poos and chuckles. After that I put it all back to my normal settings and the fork felt a lot better than it ever had.

I know some will think it was a psych thing going on but the fork was using more travel than it did previously at the same settings and I ended up having to run more rebound. Not sure what happened but the performance improved greatly.

 

[tacubaya]

Your actually using a full synthetic ester oil for lower lubrication? Can I have your scrooge mcduck piles of money you waste on high temp engine oils?

No you can't have them.

 

[tacubaya]

I did in a friend's Boxxer, and it worked very well, however I only tested short term - haven't heard any complaints yet. I think tacubaya here also did the same and had a similar experience but maybe he can comment himself.

I've tested Fox Green on a Rock Shox Domain, Lyrik and Boxxer. No problems, great feel.