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Fork ride height - single stage vs two stage stacks

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Single stage stacks are rumored to "ride higher" in the stroke then a dual, is this something most riders can notice?

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do you mean compression stacks with high speed and low speed as opposed to just a high speed stack?

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it all depends in the stack , a stiff 2 stage can ride higher than a single

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here is my logic to this. a single stage stack is less progressive, there for it has to be some what stiff through out the whole range. where in a two-stage stack you get a more progressive suspension. so with most 2 stage stacks you would have the suspension set softer where it first opens in order to absorb the small obsticles better. and it would get stiffer towards the end of the range in order to prevent bottoming. a three stage stack would probably be even more progressive meaning that it would ride even lower yet. but if you stiffened up the stack closest to the piston you would increase the ride hight but make the suspension less progressive there for defeat the purpose of a two stage stack. the two and three stage stacks seem to be more preferable in a off-road riding style. but when it comes to a motocross bike most stacks seem to be single stage or maybe just slightly a two stage. i have never heard of a three stage stack in a motocross bike and the shocks are almost always single stage in motocross. forks are usually a single stage with on or two shims breaking up the low speed stack. making it technically a 2 stage but not all that much more progressive than a single stage. any one have some input on this? not sure that i am correct but this seems to me the most logical explanation as to why a 2 stage rides lower than a single stage.

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Single stage stacks are rumored to "ride higher" in the stroke then a dual, is this something most riders can notice?

In general a single stage stack will ride higher in the stroke and yes it is noticeable.

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+1

A single stage stack has greater sealing pressure against the piston face. More force is required to begin initial oil flow through the main piston ports. Given two stacks of similar stiffness profiles, the single stage will ride higher (and have a different feel altogether).

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I would lean on a 2 stage more for offroad/woods setting than mx. Especially running a DDT setup.

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+1

A single stage stack has greater sealing pressure against the piston face. More force is required to begin initial oil flow through the main piston ports. Given two stacks of similar stiffness profiles, the single stage will ride higher (and have a different feel altogether).

different fell in that it will be less progressive and also a higher Venter of gravity. Thus making the bike feel slightly heavier and less"flickable" not saying single stacks aren't good but the average two stage stack is usually more proffered than a single. The a small trick the pros use is lower COG by lowering the rads and other components to make the bike handle.

also sorry if my first post got confusing. I was basically saying the same thing but did not word it as well lol

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the pros also how ever try to keep their bikes high I the stroke on the suspension to give them more travel..unless your ride like a pro though you shouldn't have a prob with this and you will prob prefer a 2 stage as it gives you an overall lower COG.

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Interesting points. I tend to like my bikes to ride high in the front so this is something i'm going to be testing. Right now the forks are settling to low under braking.

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Depends as Mog suggested, Anyone considered the amount free bleed that is associated with the two. CO position etc.

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Interesting points. I tend to like my bikes to ride high in the front so this is something i'm going to be testing. Right now the forks are settling to low under braking.

How much more compression damping do you think you will need to hold the fork up under braking?

What is the down side of using stiffer springs or a higher oil level?

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I'm surprised no one has mentioned the mid-valve? IMO the BV stack has zero to do with keeping the bike up in the stroke. The BV stack's only purpose is to allow the oil displaced by the cartridge rod to exit the cartridge when the volume of fluid exceeds the bleed orifice (clicker or bleed shim).

The Mid-valve in modern forks is responsible for 85-90% of the "feel" on compression. The BV must be valved stiff enough that the mid-valve does not push fluid. They compliment each other. If you want the fork to ride really high in the stroke, reduce float @ the MV and adjust the MV stack build to get the feel you want.

Too much focus on the BV stack by most people. There have been some stupid BV stacks in the past. I completely disagree with .15 shims on a BV stack.

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I'm surprised no one has mentioned the mid-valve?

:busted: well it was thought of Lew but the ? was addressing the base.. a SS stack Versus a 2S stack

But your absolutely right. :busted:

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I'm surprised no one has mentioned the mid-valve? IMO the BV stack has zero to do with keeping the bike up in the stroke. The BV stack's only purpose is to allow the oil displaced by the cartridge rod to exit the cartridge when the volume of fluid exceeds the bleed orifice (clicker or bleed shim).

The Mid-valve in modern forks is responsible for 85-90% of the "feel" on compression. The BV must be valved stiff enough that the mid-valve does not push fluid. They compliment each other. If you want the fork to ride really high in the stroke, reduce float @ the MV and adjust the MV stack build to get the feel you want.

Too much focus on the BV stack by most people. There have been some stupid BV stacks in the past. I completely disagree with .15 shims on a BV stack.

Very good point Lew! Shoot, add 1 20 or faceshim to the mid and your up in stroke more so than before!

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Interesting points. I tend to like my bikes to ride high in the front so this is something i'm going to be testing. Right now the forks are settling to low under braking.

I would start with 1 faceshim on the mid/active valve comp. side. Like Lew said the mid is where its at.

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I'm surprised no one has mentioned the mid-valve? IMO the BV stack has zero to do with keeping the bike up in the stroke. The BV stack's only purpose is to allow the oil displaced by the cartridge rod to exit the cartridge when the volume of fluid exceeds the bleed orifice (clicker or bleed shim).

The Mid-valve in modern forks is responsible for 85-90% of the "feel" on compression. The BV must be valved stiff enough that the mid-valve does not push fluid. They compliment each other. If you want the fork to ride really high in the stroke, reduce float @ the MV and adjust the MV stack build to get the feel you want.

Too much focus on the BV stack by most people. There have been some stupid BV stacks in the past. I completely disagree with .15 shims on a BV stack.

:busted: the mid is definately a main focus in how we tune.

lately, i've really got into single-stage stacks for all disciplines. i do use dual stage occasionally, but i run larger crossover diameters.

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Depends as Mog suggested, Anyone considered the amount free bleed that is associated with the two. CO position etc.

CO position?

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Single stage stacks are rumored to "ride higher" in the stroke then a dual, is this something most riders can notice?

The simple answer is yes, but there are exceptions and it depends on the size of the cross in the 2 stage stack. A 2 stage base stack can be made to ride high like a single stage if its cross diameter is not to small and has plenty of LS shims.

Example 2 stage that can ride high.

32.11x20

28.11

32.11

30.11

28.11

26.11

ect...

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