[TWISTED]

Has anyone tried using nitrogeon in their spv chambers or used it in air forks?
There is a local motocross shop that offers nitrogeon recharges for motorcycle shocks, that got me thinking. I would assume that since air expands as it warms, and nitrogeon I believe, is less suspectable to expansion. Nitrogeon might work better than air in these applications.
Would there be a problem with it eating up the seals?

 

[DHS]

yea i don't think the seals would be able to handle it. thats why Avy runs MX seals...

 

[vitox]

it will work but then again the chances you will ever notice anything are slim

remember air is 80% nitrogen anyway and the temperatures inside a bicycle suspension component arent that high, actually i think it should work better on a non spv shock since those have less air volume and seemingly the same heat to dissipate

 

[scottishmark]

Originally posted by vitox
the temperatures inside a bicycle suspension component arent that high

well Avys run up to 350degrees iirc so you'd have to guess that that's gonna have an effect

 

[vitox]

Originally posted by scottishmark
well Avys run up to 350degrees iirc so you'd have to guess that that's gonna have an effect

the air inside the chamber heats to 350 celsius?
thats a lot, aluminium gets heat treated at half that temperature. dont know what it would do for plastic or rubber parts inside either, but if thats the temperature of the air inside the reservoir then i could see how nitro would be an advantage, but i dont think it gets that hot.

 

[scottishmark]

i'm trying to remember the exact figures as Craig told me....................... i think it may be that MX sghocks runh that high and Avys were up to 280 (can remember that coming up too)

it was definitly very hot, and easily hot enough to bake the stickers off the outside of the body

 

[buildyourown]

I'm calling bs on this. No rubber seal would survive those temps. Even 280 F sounds too high. Think about it. Go work out the shock really good like on some high speed bumps ad feel the outside of the shock. Does it peel the skin off your hand? Then its not even close to those temps.

 

[scottishmark]

Originally posted by buildyourown
I'm calling bs on this. No rubber seal would survive those temps. Even 280 F sounds too high. Think about it. Go work out the shock really good like on some high speed bumps ad feel the outside of the shock. Does it peel the skin off your hand? Then its not even close to those temps.

try putting your hand on a Avy after a rough 5min dh run then get back to me

 

[buildyourown]

Originally posted by scottishmark
try putting your hand on a Avy after a rough 5min dh run then get back to me

I'm not doubting they get really hot. But you would destroy the heat treat on the aluminum and melt the seals at 280 deg

 

[kidwoo]

Originally posted by buildyourown
I'm calling bs on this. No rubber seal would survive those temps. Even 280 F sounds too high. Think about it. Go work out the shock really good like on some high speed bumps ad feel the outside of the shock. Does it peel the skin off your hand? Then its not even close to those temps.

Totally dude.

Nitrogen is used because 1) you can get it "dry" and keep moisture out of your system and 2) it's inert and won't oxidize any ferrous materials that happen to be in your shock.

Nitrogen is a gas just like the mixture of gases that make up air. Both expand/increase pressure when heated. Any difference in pressure is completely negligible.

Remember PV = nRT ?

Change in pressure and/or volume will be dependent on moles/mass of air and the change in temperature, not so much the composition of that gas.

 

[BigMike]

Originally posted by scottishmark
try putting your hand on a Avy after a rough 5min dh run then get back to me

Loan me your Avy, I'll do a run and then get back to you

 

[Craig Seekins]

Our Dhs shocks are designed to withstand temperatures of 280 degrees F, typical operating Temperature is 180 Degrees F at the shaft piston. Over longer rough rides the oil and surrounding shock body will reach this temperature also. The oil moving in and out of the remote reservoir represents only 30% of the total volume and takes a bit longer to heat up, nitrogen is used to charge the reservoir because it is clean, moisture free and it expands slightly less than air at these temperatures. In front forks the temperature increase is very small so very little advantage will be noticed, btw nitrogen will not hurt rubber seals.

 

[erikkellison]

Originally posted by Craig Seekins
Our Dhs shocks are designed to withstand temperatures of 280 degrees F, typical operating Temperature is 180 Degrees F at the shaft piston. Over longer rough rides the oil and surrounding shock body will reach this temperature also. The oil moving in and out of the remote reservoir represents only 30% of the total volume and takes a bit longer to heat up, nitrogen is used to charge the reservoir because it is clean, moisture free and it expands slightly less than air at these temperatures. In front forks the temperature increase is very small so very little advantage will be noticed, btw nitrogen will not hurt rubber seals.

Thanks for the clarification Craig. You guys need to be careful about your units. Didn't you all get yelled at by professors for messing them up on labs and exams? 280C is a lot hotter than 280F. And who came up with the idea that nitrogen would hurt seals when air would not? That makes zero sense since air is about 78% N anyway (as stated previously). Nitrogen is a really inert gas as well (not going to "eat" much of anything.
And ambient temperature should be taken into account when discussing shock temperatures. When it's 30F out, the shock may get up to 180F, but probably not. But when it's 90F out, the shock will probably get hotter than 180F.

 

[vitox]

fahrehneit!!!!!!


well that a whole different story.


btw nobody claimed nitro was going to do anything to seals, i meant that the temperature would do so if it was 350ºc, seems like buildyourown and kidwoo also meant that.

 

[ragin-sagin]

Originally posted by buildyourown
But you would destroy the heat treat on the aluminum at 280 deg

um...no.

 

[buildyourown]

Originally posted by ragin-sagin
um...no.

another F vs C mixup. Alum begins to anneal at around 300 deg C

 

[TWISTED]

OK that answers my question.
It was one of those things where your laying in bed trying to sleep but you can't stop thinking about bikes.
About the seals, I am not a scientist, just a bike rider. I know that nitrogeon is used in motorcycle shocks as well as to charge bike shocks and just wondered about using it for bikes where air is normally used in suspension. Thanks.

 

[ragin-sagin]

Originally posted by buildyourown
another F vs C mixup. Alum begins to anneal at around 300 deg C

um...yes