What's the Truth? Lubricant Sprays and Fork/Shock Seals

[Odinson]

The other day I was reading an article on enduro-mtb.com (http://enduro-mtb.com/en/enduro-long-term-test-review-2015-fox-36-rc2/) on the new FOX 36 and came across this qoute:

 

"Also we never apply any oil out of spray cans onto the stanchion tube, as some lubricants can cause rubber to swell and reduce the performance of the seal."

 

What I want to know is the following:

1. Is there any truth to this statement and if so, what causes the damage to the seals (the propellant, lube, etc.)?
2. Is it necessary to lube fork/shock stanchions - I know many will argue that the dust wipers will simply wipe off any lube you apply, but the fact is that gunk still finds its way under the dust wiper.

Any thoughts?

[Mojoman]

Sometimes I add some fork oil to the stanchions and 'pump' the fork a couple of times, you would be surprised the amount of crap that comes up, evem though I wipe them down before every ride.

[BarHugger]

Fork's (SID XX) stanchions gets a little bit of Q8 (silicone) treatment before long rides and races (+40km) as a "what-ever-you-want-to-call-it" prerace fiddle and service. Keeps everything smooth, rubbers look fine and work well, keeps dirt to minimum and stanchions still look new (no scratches or roughness). Easy to clean also....just a wipe and polish.

 

Does it work?? In my mind it does......but maybe i am just bluffing myself.

Edited October 28, 2015 by BarHugger

[Iwan Kemp]

I use silicone spray. Haven't had any issues, but willing to listen to those in the know. Have been given some Brunox to try so will report on that somewhere down the line

[raptor-22]

The other day I was reading an article on enduro-mtb.com (http://enduro-mtb.com/en/enduro-long-term-test-review-2015-fox-36-rc2/) on the new FOX 36 and came across this qoute:

 

"Also we never apply any oil out of spray cans onto the stanchion tube, as some lubricants can cause rubber to swell and reduce the performance of the seal."

 

What I want to know is the following:

 

• Is there any truth to this statement and if so, what causes the damage to the seals (the propellant, lube, etc.)?
• Is it necessary to lube fork/shock stanchions - I know many will argue that the dust wipers will simply wipe off any lube you apply, but the fact is that gunk still finds its way under the dust wiper.

Any thoughts?

 

So I asked my tjom this question a while back and he says it's a very true statement. Something to do with the composition of the aerosol lubes that is absorbed into the seals causing them to swell too much. The seals then have more "Stilton" and friction force to over come and wear out faster

[Odinson]

So I asked my tjom this question a while back and he says it's a very true statement. Something to do with the composition of the aerosol lubes that is absorbed into the seals causing them to swell too much. The seals then have more "Stilton" and friction force to over come and wear out faster

 

Interesting. It seems like it could be true. Maybe using a syringe to drop some oil on/under the dust wiper might be the better option. 

[raptor-22]

He told me to always lube with suspension oil and use the same as what's in the fork

That way you don't introduce additives that have a different effect on the seals. Once the seals swell with the oil they stabilise. Adding something else can cause the seals to swell further or even shrink

[Capricorn]

Interesting. It seems like it could be true. Maybe using a syringe to drop some oil on/under the dust wiper might be the better option. 

 

its definitely true. not all rubbers are manufactured the same (different additives, different levels of additives),and thus all don't function equally under the same operating conditions. Its such a known fact that rubber naturally absorbs oil, there are various studies done to determine whether using the world's near endless supply of discarded car tyres, as a means to mop up oil spills.

 

If you have a spare o-ring/gasket, run a small test before using: one half of the rubber sample in the OEM specced oil (the control sample), and the other half in the oil you planning on using. Test under same conditions, and see how they respond over time. Things to look for is swelling and hardening.

 

this is of course not a comprehensive test, but major differences between the control and test samples will be a clue as to what you should do

Edited October 28, 2015 by Capricorn

[Josh0]

This is an interesting thread. I was also always wondering about this matter.

 

When I notice a ring of dust accumulated on top of my fork's dust seals, I will wipe most of it off first then I will apply a small amount of Wynnflon (Teflon) with an earbud to the seal. Following with a few compression cycles to dislodge the rest of the dust, then wipe all of it off again.

 

I hope the Wynnflon is kind to seals, the can says it is O-ring friendly.

[Mr X]

"Also we never apply any oil out of spray cans onto the stanchion tube, as some lubricants can cause rubber to swell and reduce the performance of the seal."

 

This statement does not make sense to me. Never apply anything because some cause rubber to swell. Rather tell us which lubes are ok to use, surely Bronux will not do this?

[Odinson]

It's interesting because you actually have a number of aerosol products which are marketed as "stanchion lube". 

 

Is it possible that such sprays can be formulated in a manner which does not damage the rubber?

[s14phoenix]

I have found that putting some float fluid with under the seals (syringe with a bendy needle) and on the stanctions then compressing slowly to let the fluid seep in and under and then releasing the shock gets some gunk out under the seals.

 

When no more gunk comes out I make sure there is a bit of fluid under the seal to keep it smooth. This all between services and after a gentle soapy wash after almost every ride and especially after the dusty rides lately.

 

And I never go near my bike with a high pressure hose. gentle wash down and rinse

 

float fluid is really the best on the fox forks but I know it is expensive - but stanctions are more expensive.

 

I am sure however there is lube/oil types that wont cause problems but is it worth a gamble?

[IH8MUD]

Interesting thread/question. 

 

Drew,  from Stoke suspension will shed light on this  topic. 

[raptor-22]

Yes aerosols that use a non petroleum propellant can be seal friendly. Typically co2.

However it's the oil itself that presents the problem. Hence the suggestion to not use aerosol products but rather the same oil as is used in the fork

[Iwan Kemp]

He told me to always lube with suspension oil and use the same as what's in the fork

That way you don't introduce additives that have a different effect on the seals. Once the seals swell with the oil they stabilise. Adding something else can cause the seals to swell further or even shrink

 

Sounds like the best advise. 

[Mawbs]

i use Fork Juice and have to say it makes the stanctions feel silky smooth