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Ride Instigator
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TimZ said:
I have only run coil suspension. Are there any special issues for running air suspension in the winter?
You're getting pretty serious about this air business ain't ya ;) .

I never liked the way that Cane Creek that I had on the Isis originially felt in the colder weather, that's part of the reason I went with the Romic. It seemed that I had less small bump compliance and dampening wasn't as good in the colder temps.

Of course that CC was old technology so let's see what some folks have to say about some of the newer air shocks that are out there now.

You riding this weekend? Let me know when and where...seems everyone and even Derek is hiding from the cold this year!
 

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I set my bike outside until it's cooled off, then air the shock or fork up to the usual pressure. I have found that my Fox rear shock likes to have the air chamber cleaned and regreased at the beginning of the cold season (below freezing), or it will leak a little. But this is very easy to do at home; there are even directions in the manual. Anyway, it's probably good to do at least once a year anyway.

Other than that all my air shocks and forks work fine in the cold.
 

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All 26.5" all the time!
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Air becomes more dense as the temperature drops. You'll see this as a slight pressure drop in your air sprung suspension. As said above, just allow the temp between the outside air and your fork/shock to equalize and set to desired pressure.

The damping fluid plays a part as well. Low temps mean thicker oil, so you'll need to adjust the damping rates with adjustments on the outside of the fork/shock or with thinner suspension oil.
 

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I definitely notice a loss in air pressure in my DHX-A when I take it out in the cold. It's been in the teens here, and the loss of air pressure is noticeable now. Definitely let it cool off before you adjust the pressure IMO.
 

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I don't think you're generating that much friction to heat up the air in the chamber personally, at least not in the temp range we're talking about (sub 20's?).
 

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hands up who wants to die
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Won't the air in the shock heat up quickly once you start riding due to suspension action/pressure?

How does one account for that if airing-up the shock when it is very cold, as a few of you have suggested?

thx
-r
 

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I like to ride my bike.
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Same problem

My swinger 3 way looses lots of pressure just from a bunnyhop in cold (30 deg) temps. But it also feels like it is bottoming, yet the little o ring, or whatever measures the travel is only halfway through. So oddly it bottoms out halfway through it's travel in cold weather.
Oh well.
 

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hands up who wants to die
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I'm no engineer, but my tire pump noticeably heats up from pressure when pumping a tire up to 35psi... Consequently, I bet my 2" stroke Fox fork is too when my roughly 200lbs (rider, gear and bike) are pushing on it hundreds (?) of times per minute while trail riding.

Maybe it's not going to be 100 degrees in the shock canister, but it's going to be significantly warmer than the outside air, I'm guessing.

This doesn't change the fact that if more air is lost due to cold temps before the ride (you keep your bike in a cold garage or during the trip to the trailhead on a bike rack), you need to put more air in. But I'm just questioning at what temp it makes sense to dial in the air pressure exactly; I figure maybe 20 minutes into the ride would be a good time.

-r
 

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aka greyranger
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cold???

Ricko said:
You're getting pretty serious about this air business ain't ya ;) .

I never liked the way that Cane Creek that I had on the Isis originially felt in the colder weather, that's part of the reason I went with the Romic. It seemed that I had less small bump compliance and dampening wasn't as good in the colder temps.

Of course that CC was old technology so let's see what some folks have to say about some of the newer air shocks that are out there now.

You riding this weekend? Let me know when and where...seems everyone and even Derek is hiding from the cold this year!
Cold = indoor bmx, try it you'll like it.
 

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rpet said:
Won't the air in the shock heat up quickly once you start riding due to suspension action/pressure?

How does one account for that if airing-up the shock when it is very cold, as a few of you have suggested?

thx
-r
If the air inside the fork/shock heats up when in use, it does so whether it's 0 degrees or 100 degrees. So you still need to compensate for the change in temperature.
 

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Interesting thread - I went out on Sunday in very cold conditions and experienced nearly complete loss of air in my Z1FRSL. When I went hoem and pumped back up all was fine. Although I have to say that I have not checked the pressures in the fork for about 6 months

Kwack
 

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kwack, I had no problems with my Marzocchi MX Pro last year down to 0 farenheit. This year I bought a new Marzocchi All Mountain 1 and the first ride under 30 degrees it went flat (no air pressure). Filled it up at home and it seemed to hold air fine. Next ride was 25 degrees and it went flat in 10 minutes. I consider this a defect so I sent it back to Marzocchi. Hopefully it will come back fixed!! Luckily I have a spare fork! I'll post how it works out. I would send yours back also if it is still under warranty.
 

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Don't worry about temperature variation affecting your shock air pressure. As long as you check the pressure/sag before you set off, it won't make any difference whether it's freezing cold or steaming hot. Unfortunately, the same cannot be said about changes in oil viscosity and seal friction. Both of these can have a significant effect on shock performance. In very cold weather, you'll generally see increased stiction and higher damping levels. You'll notice this most at the start of a ride when everything is very cold - particularly if your bike is stored outside.
 

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rpet said:
I'm no engineer, but my tire pump noticeably heats up from pressure when pumping a tire up to 35psi... Consequently, I bet my 2" stroke Fox fork is too when my roughly 200lbs (rider, gear and bike) are pushing on it hundreds (?) of times per minute while trail riding.

Maybe it's not going to be 100 degrees in the shock canister, but it's going to be significantly warmer than the outside air, I'm guessing.

This doesn't change the fact that if more air is lost due to cold temps before the ride (you keep your bike in a cold garage or during the trip to the trailhead on a bike rack), you need to put more air in. But I'm just questioning at what temp it makes sense to dial in the air pressure exactly; I figure maybe 20 minutes into the ride would be a good time.

-r
In this case, the heating comes mainly from friction in the seals rather than pressure. This does happen in your shocks too, but they don't get very hot (or even warm) on mountain bikes. Certainly not enough to cause any problems.
 

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i have the same fork Z1 FRSL and experiencing the same symptons in cold weather...i can hear the air leaking from the seals not the valve. Is there a fix with out having to send it back?
 

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tia4 said:
i have the same fork Z1 FRSL and experiencing the same symptons in cold weather...i can hear the air leaking from the seals not the valve. Is there a fix with out having to send it back?
I was having the same problem with my AM 1. I sent to Marzocchi because it was still under warranty. Marzocchi tech called me today and said it was losing air because an excessive amount of dirt got past the dust seals and was not letting the air/oil seals, seal properly when cold. However, while it was there, tech checked whole fork over carefully and found that the steering tube was damaged and both upper and lower stanchions were bent. Sooooo after some discussion, they warranted uppers, lowers, bushings and seals. I had to pay for the steering tube $50 and they are using the existing dampening rods and stuff so it's mostly a new shock. Bonus is that the lowers are being replaced with black ones so I can get rid of that ugly tan color. I'm glad they covered most of the items, says alot for their customer service. I just hope it's FIXED! If you are under warranty, opening the fork will void the warranty so I would send fork in. Otherwise I would replace the seals with Enduro seals from enduroforkseals.com as they are cheaper and better than factory seals.
 
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