Udi - clear your PM's. I have that info you requested. 
2012 fox 40 breaking in period?
- Thread starter Optimax150
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Tbh I have always used a diesel engine oil of varying sorts, always one without seal swellers, but that's all I cared about. I did this because I had no idea there was actually an oil developed specifically for the purpose and shock fluid is not great for lower lube.
I might actually give the Fox green a go, though I'm not sure how much tangible difference it will make vs the feeling of a fresh rebuild.
I might actually give the Fox green a go, though I'm not sure how much tangible difference it will make vs the feeling of a fresh rebuild.
You're still digging this hole? Might want to re-read previous posts.
Yeah I see.. the additives destroing your fork in minutes.
Clearly not what was said.
You're commenting on the performance of a specific product which you haven't even tried, against a vast array of products (motor oils) which vary hugely from brand to brand, and model to model.
If you can't understand that simple distinction then you should probably stop giving people advice on how to run their $1000+ products.
You're commenting on the performance of a specific product which you haven't even tried, against a vast array of products (motor oils) which vary hugely from brand to brand, and model to model.
If you can't understand that simple distinction then you should probably stop giving people advice on how to run their $1000+ products.
wow...alot of lopsided stupid here. ****ing auto oils will and do **** up seals/bushings and plastics.
Really, because cars don't have seals amirite? Seal swellers are not in a lot of engine oils. I would love to see your testing to show where all engine oils ruin the polymer bushing coating and ruin seals. My bushings in my 06' 36 van r's are perfect (the stauncions, not so much) and I've been using diesel oil for ages.
Not so stay Fox green isn't better for the task, but there are plenty of oils that do fine and your silly "it's a bicycle, it needs specific bicycle lubricants" bull**** is halarious.
That's a legitimate statement because you used a particular product and it worked fine for you, however the problem occurs when someone suggests that other people do the same - because then customer X goes and purchases motor oil product Y off the shelf, puts it in fork Z, and then all of a sudden you have a risk of product damage or inferior performance because:
- Y and Z are likely to be products different to those which you used
- Y may be the same oil you used, but it may react differently in fork Z vs. your own fork
- On the rare occasion both were the same, I'd personally still be dubious of the internet public's opinion over that of the manufacturer (in general - not a stab at you personally) - there's a difference between 'works' and 'works the best + works well in the long term'.
- Y and Z are likely to be products different to those which you used
- Y may be the same oil you used, but it may react differently in fork Z vs. your own fork
- On the rare occasion both were the same, I'd personally still be dubious of the internet public's opinion over that of the manufacturer (in general - not a stab at you personally) - there's a difference between 'works' and 'works the best + works well in the long term'.
Run fork oil in your car then smart guy. It's not my job to tell people its cool to run high detergent auto oils in their bike, the burden rests on you guys to prove it's fine.
Im ok paying the few dollars more for oil thats been partially or fully formulated for the job at hand and not an engine oil designed to scrub sulfur from the inside of a diesel crankcase.
Why stop at engine oil? Vegetable oil is cheaper. Or even those sachets of hand lotion that are on the sink in the hotel. Personally, I'm not some sheep being a sucker for manufacturer's and their expensive proprietry lubes and engine oils. I rub my stantions with bacon fat before I go for a run. It works fine and its free with any bacon and egg muffin.
Home heating oil is like diesel why not run it too.
So you guys run your Rs forks with the standard damping oil in the lowers too because the manufacturer dictates it?
If this would be true there wouldn't be multiple statements that motor oil works good and also some where people complain but I read not one. Dealing with a bicyle fork is not rocket science.
This little company called SKF may have done some research on the topic of the lubrication of their seals in both linear motion and rotary motion.
Fun fact: Moto fork oil can be used pretty damn well at gas-premix on 2-strokes motors if you're in the field and need to mix gas to get back to camp. About 75cc/gallon at 50:1.
'Multiple statements' by a bunch of guys on the internet isn't conclusive evidence about EVERY motor oil product on the market. This is such a simple concept yet you can't seem to grasp it.
I've measured and seen reduction of ID in RS boxxer bushings (i.e. coating swelling) after running them long term with non-factory oils in the lowers - variations significant enough to increase stanchion stiction noticeably with no seals installed. Most people would just think their boxxer needed a service and that it was normal - not many people would stop and think the oil was affecting their bushings. Many of those people would also jump on the internet and say the oil they chose worked great, every fork feels great after a service.
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I've always noticed this too, and usually just choose not to antagonize these people. The Maxima green-label oil in particular is very low quality and breaks down VERY fast. It is popular opinion in the moto world that it doesn't belong in any performance fork or anything set up for long-term use. Yet people still think it's the cats ass because their suspension doesn't feel clapped out anymore due to all the other work that was done on it at the same time.
As Udi said, it's the bushings that are an area for concern. For dirt bikes/street bikes, seal manufacturers will actually recommend letting the seals soak in the thickest motor oil you can find just before you install them, and don't use grease. I find this to be really messy personally, and don't like the lack of grease. In any case, bushing wear/swell/deformation is an issue.
One big difference with suspension fluids is the alcohol content. I know this because it actually ate away the cheapo plastic caps in one of the drain pans I used once which was supposed to be for motor oil. Turned out it stated not to use acetone, alcohol, or MEK in there for long periods of time, so I just dump it quickly now into a bucket.
Hey guys, just a quick one -
Do I need to use the foam seals in my 2011 40s? I forgot to put them in when I serviced them and dont want to pull them apart again. Would they be okay for a few days riding? I normally change lowers oil every 2 races or so anyways so I dont mind putting the foam seals in then.
Do I need to use the foam seals in my 2011 40s? I forgot to put them in when I serviced them and dont want to pull them apart again. Would they be okay for a few days riding? I normally change lowers oil every 2 races or so anyways so I dont mind putting the foam seals in then.
Well my fork is starting to break in now. The fork moves more freely. Starting for the need to add compression. I'm using more travel than I think I should. I haven't put much compression yet, just getting the feel for it still.
Udi-what spring are you running? I noticed in a thread you weigh as much as me, 180,
or anybody else. Just curious to see what your setup is. I know I got add more compression but so far I got 10 clicks in on hi spd compression and about 7 clicks of low spd.
Udi-what spring are you running? I noticed in a thread you weigh as much as me, 180,
or anybody else. Just curious to see what your setup is. I know I got add more compression but so far I got 10 clicks in on hi spd compression and about 7 clicks of low spd.
Stock blue Ti, lots of compression damping. I ran HS fully closed and about 50% of the total range of LS on the stock damper (up to 75% for really steep tracks). Right now I have the cartridge valved firmer (doubled face comp shim) and run less LS - maybe 30-40%. The stock damper has plenty of range though.
These settings vary depending on riding style, speed and terrain/gradient - my only general suggestion is that both the 40 and RC4 work well with a little more HS in relation to LS, as it gives stronger mid-speed support without the harshness that you get with a lot of LS.
Given that, I'd leave your LS where it is and see if turning up the HS gets you closer to a level of support you're happy with.
These settings vary depending on riding style, speed and terrain/gradient - my only general suggestion is that both the 40 and RC4 work well with a little more HS in relation to LS, as it gives stronger mid-speed support without the harshness that you get with a lot of LS.
Given that, I'd leave your LS where it is and see if turning up the HS gets you closer to a level of support you're happy with.
Yeah that's what I've been doing, I did add a couple of clicks of low spd, now about 9 or 10 now. I will probaly leave it there for now.
A lot of this is all rider preference, style and local terrain. I was just wondering to sort of compare.
If you are on the stock spring and running a lot of compression, why not go up in spring rate? Was the stiffer spring to harsh or what? I done a little reading about lightly sprung heavy dampening, heavy sprung light dampening.
Could you explain this a bit, please?
I'm not a suspension expert, but my common sense would say increasing HS compression would cause harshness (reducing the shim bending on high speed hits may lead to choking of the circuit), whereas the LS would not (in high speed hits the LS valve hole chokes and the oil flows mainly through the shims of the HS circuit).
Considering that pro forks are usually valved and damped much firmer than the consumer models, running near the maximum range of a consumer-valved damper isn't really that crazy in the big scheme of things.
For whatever it's worth, I'm in the correct weight range for the blue, and only hit 180 once geared up. I have ridden and could get away with the green, but I think the correct spring for me is the blue, especially given my riding these days isn't just all steep stuff. Sag and travel usage both seem to be correct.
Yes, that's how it would work if the adjusters did exactly what their name suggests, however in the case of most real-world dampers that's not entirely the case. Without getting into too much detail, if you run the LS closed and the HS fairly open with the premise of "support with the ability to easily blow off under impacts to prevent spiking", what you'll actually get is a fork that is actually fairly harsh over small bumps because it is difficult to get moving (because the damping is kicking in at very low shaft speeds), and may not even offer that much support when you hit a hard corner / g-out (because it exceeds the shaft speed threshold and opens the HS valving too easily).
If the piston and valving are well designed (in my opinion) the HS adjuster should not be able to cause the damper to spike significantly (or choke as you say) within reasonable operating shaft speeds for the application. If the damper is designed this way, you would actually be using the HS adjuster to control your 'mid-speed' damping - if you imagine the range between low and high - which is a much more useful area of compression adjustment (about the shaft speed range that would be affected by the aforementioned hard corner / g-out).
Of course too much preload on the stack and you will induce harshness / spiking - my suggestions were specifically for the Fox products in question. They seem to have done a good job of giving the end user a large degree of adjustability while simultaneously preventing them from going too far.
Depending on the product there will be variations in the range of control each adjuster gives you, and it's well worth learning what that is on whatever suspension you ride.
Alright, thanks for the explanation!
One more thing I have been wondering is that increasing LS compression reduces the shaft speed required to bend the shim stack, doesn't it? And if that's the case, does it reduce the total damping effect with the threshold speed?
Let's say we the shaft speed is X m/s. In the first case the low speed valve hole area is Y mm^2. In this configuration the shim stack does not open at all.
In the second case the LS area is for example 0.8xY, which causes the pressure rise above the shim stack threshold at speed X. Now there are less oil going through the LS hole, but more oil going through the shim stack. Which scenario produces more damping effect at speed X, if the shim stack is exactly the same in both cases?
One more thing I have been wondering is that increasing LS compression reduces the shaft speed required to bend the shim stack, doesn't it? And if that's the case, does it reduce the total damping effect with the threshold speed?
Let's say we the shaft speed is X m/s. In the first case the low speed valve hole area is Y mm^2. In this configuration the shim stack does not open at all.
In the second case the LS area is for example 0.8xY, which causes the pressure rise above the shim stack threshold at speed X. Now there are less oil going through the LS hole, but more oil going through the shim stack. Which scenario produces more damping effect at speed X, if the shim stack is exactly the same in both cases?
The damper with the 0.8xY mm^2 port area will have more damping at speed X than the damper with Y port area, assuming the shaft speed is high enough to make the shims bend in the scenario with 0.8xY port area. See my markings in red below:
The key thing to realise here is that damping always increases with shaft speed, what the shim stack does is allow damping to increase at a linear or digressive rate relative to shaft speed - compared to a port-only damper which would result in damping increasing progressively (and thus cause spiking, especially in compression where shaft speeds reach much higher than in rebound).