# Air vs Coil Fork?



## Guest (Oct 25, 2010)

Ok, first first. I've never, ever tried an air fork, and haven't tried a fork out of the reach or rst. This puts me on a place where I can't judge the difference, and I'm asking you pros.

Why do people prefer coil over air? Quoting something from the web: Air is good, but coil will always be better. ????

Air doesn't bottom, out, and has a non-linear spring rate. Wouldn't that be ideal for soaking up small bumps?


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## schultzboy (Aug 20, 2010)

perhaps coil is better because you could better tune the fork per rider if you inserted coils of different spring rates.

air may not "bottom out" like a traditional coil does once it it fully compressed, but there is a limit to how far any fork travels and they will eventually have to stop moving.


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## HamfisT (Mar 31, 2010)

Never heard that quote myself!

Air forks are infinitely more adjustable.


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## Crosstown Stew (Aug 16, 2008)

I prefer air for xc but have heard from people who do more freeriding and dirt jumps they prefer coil. If your upgrading from a rst I think you'll be impressed with whatever you get. If your not looking at a new fork price point, you can usually find good deals in the classifieds around 250 for a good fork and for another 75 get a rebuild kit and oil. 

One thing about air if you ride a lot, RS recommends changing oil every 50hrs and complete rebuild every 100. Fox is a little longer I think but still if you ride a lot, probably a good idea to learn how to rebuild it yourself.


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## TheMajor (Sep 13, 2010)

I was in this position in this position a few weeks ago. Basically, I came to the following conclusion:

Air) Light, highly adjustable (can be overly complex), relatively plush,

Coil) a little heavier, simple adjustments (but for major adjustment springs need changing), really plush.

Basically, if you want to ride and not worry about setting and adjusting forks, get coil. If you want a lighter bike and don't mind the extra hassle with adjustment, get air.

I went with coil just because I wanted plush forks that just worked. In the past, coil and air were really different but as the technology developed they became more and more similar. If you go fox you will be happy with either.


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## Guest (Oct 25, 2010)

Thanks for all the replies!
What is plush?


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## theMeat (Jan 5, 2010)

Plush = Cadillac
Not plush = wrangler


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## DBnoob (Oct 6, 2010)

So for trails and off-road not plush is best..LOL


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## TheMajor (Sep 13, 2010)

DBnoob said:


> So for trails and off-road not plush is best..LOL


Yeah, I have an off road cadillac for that reason.

Plush means luxurious/expensive/smooth in general. For bikes and suspension, smooth.


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## Guest (Oct 25, 2010)

Why would DHers prefer coil? No bottoming out, and really easy to adjust! ???


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## cncwhiz (Sep 8, 2010)

I had never run an air fork and heard they were good for heavier riders. Mainly good for versatility in adjustment. Add air for a tighter suspension, remove air to get more travel and plush. Mine are adjusted to wear they almost bottom out but have about 1/2" of clearance before they do. You want to be able to get as much use out of your suspension as possible.

Whatever you do, be advised you will need a shock pump for an air fork. It is a special pump for adding air. Some of the high end forks come with one but most don't from my experience.


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## bad news (Jul 12, 2008)

This thread is pretty much the blind leading the blind.

Modern air forks are very good. They are lighter than coil sprung forks and easily adjustable for rider weight and riding style by a quick air pressure change. Hit one hard enough and it will bottom just like everything else.

Coil spung forks are heavier. If you want to change the spring rate to match the rider's weight and style, outside of a small window of adjustment afforded by preload you are buying a new spring. 

So why coil? Coil sprung forks feel different. In my opinion coil is still the king of small bump compliance. Fewer seals, fewer orings, fewer things in general. They also ramp up a little differently as they go through the travel.

I personally like coil sprung stuff. I think it is worth the extra quarter pound. Put more in perspective, all the work that has gone into air stuff has been to make it feel as good as coil.


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## Guest (Oct 26, 2010)

How is it possible for air forks to bottom out? You can't compress air to nothing, can you?

And how does coil feel different?


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## bad mechanic (Jun 21, 2006)

icalebkim said:


> How is it possible for air forks to bottom out? You can't compress air to nothing, can you?


Come on, think about it. You're not compressing it to nothing, because the air chamber is longer than the fork has travel.


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## bad news (Jul 12, 2008)

It's not nothing. There's still a little space in there to squish it into even at full travel.

Coil still has superior small bump compliance combined with different, often less progressive ramp up through the travel. It makes for a plusher feeling fork.

I'm talking about decent hardware here, not $100 junk. For whatever reason a lot of people ride a $100 RST coil fork, go to a mid range air fork, and declare coil to be inferior.


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## highdelll (Oct 3, 2008)

coil fork with small air chamber for progressive tuning


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## bad mechanic (Jun 21, 2006)

highdelll said:


> coil fork with small air chamber for progressive tuning


At that point, why not just an air fork with a large air chamber?


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## highdelll (Oct 3, 2008)

bad mechanic said:


> At that point, why not just an air fork with a large air chamber?


wallowy vs. small bump.
you cant fine tune the ramp-up with the air either IMO


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## bad mechanic (Jun 21, 2006)

highdelll said:


> you cant fine tune the ramp-up with the air either IMO


Sure you can, by adding or removing oil from the air chamber.

Also, how do you figure an coil/air fork has better small bump compliance than an air fork? The coil/air has just as many seals and o-rings.


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## Koppuh Klyde (Jul 13, 2010)

From a n00b standpoint, why ask the question at all? I would surely learn while having an "entry level" coil. Once I felt that Ive learned what I can the answer would seem obvious. Ive thought about this question before and decided that a mid level coil would be the best replacement for my entry level Dart 3. 

I think OPs experience should be the guage for which fork to buy. Not how much cash you have to blow on it.


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## the-one1 (Aug 2, 2008)

bad mechanic said:


> Sure you can, by adding or removing oil from the air chamber.
> 
> Also, how do you figure an coil/air fork has better small bump compliance than an air fork? The coil/air has just as many seals and o-rings.


Coil usually has one less seal/o-ring.

Example: 
Flox Float RLC. The air piston is a seal.
Fox Vanilla RLC. There is no seal where the coil spring is.


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## highdelll (Oct 3, 2008)

bad mechanic said:


> Sure you can, by adding or removing oil from the air chamber.
> 
> Also, how do you figure an coil/air fork has better small bump compliance than an air fork? The coil/air has just as many seals and o-rings.


Maybe have a point I'm no 'expert' at by any means  
it sure seems like a pain though tuning via adding-removing oil.
not as bad as compression damping tuning with shim stacks, but still a pain more than a pound or two of air...

Are you a tuning expert?
I know you're pretty experienced w/ other things.


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## bad mechanic (Jun 21, 2006)

the-one1 said:


> Coil usually has one less seal/o-ring.
> 
> Example:
> Flox Float RLC. The air piston is a seal.
> Fox Vanilla RLC. There is no seal where the coil spring is.


The forks Highdell and I are discussing are the Marzocchis which have a coil spring, and an air spring to set preload. Hence, a coil/air (which is what I wrote) fork which has the same amount of seals as an air fork.


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## bad mechanic (Jun 21, 2006)

highdelll said:


> Maybe have a point I'm no 'expert' at by any means
> it sure seems like a pain though tuning via adding-removing oil.
> not as bad as compression damping tuning with shim stacks, but still a pain more than a pound or two of air...
> 
> ...


I'm not an expert; just a guy who does his own work.

I've used a couple of those Marzocchi forks before, so I do have some experience with them, and, opposite of you, the air preload always bothered me, as it was adding complication to a coil fork. It also bothered me I had the complications and stiction of an air spring with a coil fork. I've since switch all my bikes over to Fox air forks, and the simplicity is nice. By the way, adding or removing oil isn't a big hassle, and rarely done.

All you do is depressurize the fork, remove the left cap, do what you need to do, replace the cap, and re-pressurize the fork. It's also nice because the added oil increases the rate the progression, without needing to increase the air pressure.


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## the-one1 (Aug 2, 2008)

:skep:  
Where were you guys talking about Marzocchi forks? I thought it was forks in general.

I too have an older Marzocchi Marathon XC and I hated the air preload. You are right that it adds loads of stiction if pressurized beyond a certain psi.


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## bad mechanic (Jun 21, 2006)

the-one1 said:


> :skep:
> Where were you guys talking about Marzocchi forks? I thought it was forks in general.


Highdell said "coil fork with small air chamber for progressive tuning", and Marzocchi is the only one using this system. Try and keep up here...


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## highdelll (Oct 3, 2008)

Well, I'm no mathentologist, but I have a 'sense' of how things werk - even though I won't have formulas to back it up  - I'll try do draw up some graphs of what I mean.

I too do my own stuff and consider myself to be pretty bright.


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## highdelll (Oct 3, 2008)

bad mechanic said:


> Highdell said "coil fork with small air chamber for progressive tuning", and Marzocchi is the only one using this system. Try and keep up here...


Manitou as well and other C/O shocks w/ piggy-backs too


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## bad mechanic (Jun 21, 2006)

highdelll said:


> Manitou as well and other C/O shocks w/ piggy-backs too


Are we talking about forks or shocks here? If we're talking shocks, the only one I know of which used an air preload with a coil was Stratos.


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## highdelll (Oct 3, 2008)

bad mechanic said:


> Are we talking about forks or shocks here? If we're talking shocks, the only one I know of which used an air preload with a coil was Stratos.


Same difference man, different ends of the bike :thumbsup:


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## Guest (Oct 27, 2010)

Yeah... forks...
But everyone's going into a argument here so I'm confused!


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## highdelll (Oct 3, 2008)

icalebkim said:


> Yeah... forks...
> But *everyone's* going into a argument here so I'm confused!


who? - point 'em out and I'll kick they're ass...there ass...their ass...
anyways...


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## highdelll (Oct 3, 2008)

Ok, here's my graphs... 
they're super cool


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## bad mechanic (Jun 21, 2006)

Regarding shocks, like I said, the only shock I know of which used an air preload was the Stratos, and that hasn't been made for a long while.

Looking at the graphs, I'd simply ask why you're not just using a air fork to begin with.


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