Marz. 55RC3 Ti setup

I have had Marzocchi forks in the past with the air preload but this one has air preload on one side and a coil preload dial on the other. in the past I would normally use the air side to adjust the spring rate what is the purpose of the coil preload as well?

The air chamber is considered to be the air assist and is supplementary. Meaning that while it is classified as a coil fork, you would put in a few psi if you are finding it too soft or are a heavier rider. In my case, I am a very light rider so I took all the air out of the air chamber and ride only on the coil.

The air preload is just to pump air into the oil chamber. Increase in pressure = increase in damping. Its a really cheap and in my opinion ineffective way to preload a fork because it acts more like a platform rather than a preload.

The coil preload gives a feeling akin to increased spring rate, still keeping that nice supple feel from coil suspension.

I have that fork, and use the spring preload to set up my sag, 0 psi in the air chamber and then add air to make the fork more progressive near the end of the stroke.
This way, I can set my fork up with 30% sag with spring preload for the small bump plushness, and still have a stroke which provides progressive bottom out resistance instead of relying on the compression damping circuit, which also decreases small bump compliance when it's used.
For climbing type stuff, I can crank the compression damper to stiffen the fork, and maintain a spring rate which works for me.
For my weight, this all means I can run lightweight fluid for that supple feel and to only engage the compression damping when I want it.
My one gripe with Marzocchi's RC3 setup, is that the rebound is on the top and the compression is on the bottom. I use my compression adjuster far more than the rebound adjuster and it would just be more convenient with the more often used control placed within reach from the top of the bike.

With my 2011 I have 1-2 clicks of coil preload (basically nothing), no air assist, and about 8 turns of LS/HS compression. I'm using all of my travel, but with good support when on the brakes or doddling over slow rough stuff. I'm about 185bs (maybe 190lbs loaded), and this nets me about 25% sag, maybe closer 30% if i'm right over the bars in an attack position.

Steve

I have that fork, and use the spring preload to set up my sag, 0 psi in the air chamber and then add air to make the fork more progressive near the end of the stroke.
This way, I can set my fork up with 30% sag with spring preload for the small bump plushness, and still have a stroke which provides progressive bottom out resistance instead of relying on the compression damping circuit, which also decreases small bump compliance when it's used.
For climbing type stuff, I can crank the compression damper to stiffen the fork, and maintain a spring rate which works for me.
For my weight, this all means I can run lightweight fluid for that supple feel and to only engage the compression damping when I want it.
My one gripe with Marzocchi's RC3 setup, is that the rebound is on the top and the compression is on the bottom. I use my compression adjuster far more than the rebound adjuster and it would just be more convenient with the more often used control placed within reach from the top of the bike.

How much do you weigh?

With my 2011 I have 1-2 clicks of coil preload (basically nothing), no air assist, and about 8 turns of LS/HS compression. I'm using all of my travel, but with good support when on the brakes or doddling over slow rough stuff. I'm about 185bs (maybe 190lbs loaded), and this nets me about 25% sag, maybe closer 30% if i'm right over the bars in an attack position.

Steve

Thanks. I'm about 170lb and I don't think I need any coil preload or air assist. I imagine lighter riders are kind of SOL with this fork? I don't believe there are lighter spring options. I must be just on the minimum weight range for this fork.

I'm about 155 with gear, and get full travel without touching bottom. Like I said, I run lighter weight fluid which doesn't engage the damping circuitry too harshly when pressurized. I run a couple clicks of spring preload and don't recall off hand how much psi, but I think it's somewhere around 10psi

The air preload is just to pump air into the oil chamber. Increase in pressure = increase in damping. Its a really cheap and in my opinion ineffective way to preload a fork because it acts more like a platform rather than a preload.

The coil preload gives a feeling akin to increased spring rate, still keeping that nice supple feel from coil suspension.

Woah dude, do you live in opposite World? What you just said is pretty much all completely backwards.

An increase in air pressure should not increase the damping. How does pressurizing the damping fluid increase the damping force?

Both the coil and air preload on that fork will do exactly that, preload the suspension. This means that the fork will not move from it's fully extended position until the break-away force is produced. Preload is dissimilar to a platform because a platform requires a break-away force to initiate movement at any settled position in the travel.

Also coil preload will not affect the spring rate. Air preload however will affect spring rate(edit). Additional air preload will add a preload force and make the spring rate more progressive, especially towards the end of the stroke.

In my experience with Marzocchi forks of this type I use zero coil preload, 4-5 pumps of air in the air preload, and compression damping to taste.

Woah dude, do you live in opposite World? What you just said is pretty much all completely backwards.

An increase in air pressure should not increase the damping. How does pressurizing the damping fluid increase the damping force?

Both the coil and air preload on that fork will do exactly that, preload the suspension. This means that the fork will not move from it's fully extended position until the break-away force is produced. Preload is dissimilar to a platform because a platform requires a break-away force to initiate movement at any settled position in the travel.

Also coil preload will not affect the spring rate. Air preload however will affect preload. Additional air preload will add a preload force and make the spring rate more progressive, especially towards the end of the stroke.

In my experience with Marzocchi forks of this type I use zero coil preload, 4-5 pumps of air in the air preload, and compression damping to taste.

I think you meant to say that air preload will effect spring rate. I too was curious how air preload would effect the damping too…..or did Marzocchi invest in some Curnutt tech..?

when a Zoke is pressurized on the damper side, there does always seem to be an increase in damping. My head is not cone shaped enough to explain why, but with the many many forks I have serviced this always seems to be the case.

I think you meant to say that air preload will effect spring rate.

Good catch Bryan, now fixed.

Does adding air preload exert air pressure on the shim stack in a 'zocchi? If so, increased air preload -[HTML_REMOVED] increased preload on shimstack -[HTML_REMOVED] knee in high/low speed damping turning point moved to higher shaft velocities -[HTML_REMOVED] increased damping. This is exactly how the boost valve on the DHX 5 works.

And just because it's fun to pick holes in Timmy's comments,

Both the coil and air preload on that fork will do exactly that, preload the suspension. This means that the fork will not move from it's fully extended position until the break-away force is produced.

This is BS.

Even without preload, a fork (or shock) will sag until the restoring force of the spring is equivalent to the weight of the rider acting down. Beyond this sag point, a softer spring with increased preload will require less force to compress it further into it's travel than a stiffer spring with less preload.

You're welcome.

Still though is it true that there are no other spring options? That would seem quite retarded. All these adjustments are great for balancing your linear vs ramping suspension characteristics and so on but without starting with the correct spring rate your never going to have a high performing suspension.