Bypass theory

ADSRACINGSHOCKS

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One of the main goals of us joining this forum is to help educated the masses about performance off-road shock absorbers. We might not tell you all of the fancy tuning secrets but we love to share theory with the end users so that they may enhance their suspension experience. Diagrams shown are an older set of 2.5" x16" 4 tubes with staggered compression tubes and overlapping rebound, All current race style designs feature overlapping compression as well as overlapping rebound tube layouts.
 

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Whats the theorys behind running the tubes in parallel vs series?
we call it staggered vs overlapping, staggered is more old school, think of total fluid flow on a staggered set up you only have 1 tube to flow fluid through the amount of flow can max out quickly and fluid must flow thru the piston valving, if we open up the flow on the piston to allow the shaft speed to increase then we kill the ultimate bump zone potential, if we add more flow with tubes then the fluid does not need to flow through the piston and the bump stage can be more effective due to the amount of valving you can put on the piston to control fluid flow 1673969354831.jpeg
5 tube sexyness
 
we call it staggered vs overlapping, staggered is more old school, think of total fluid flow on a staggered set up you only have 1 tube to flow fluid through the amount of flow can max out quickly and fluid must flow thru the piston valving, if we open up the flow on the piston to allow the shaft speed to increase then we kill the ultimate bump zone potential, if we add more flow with tubes then the fluid does not need to flow through the piston and the bump stage can be more effective due to the amount of valving you can put on the piston to control fluid flow View attachment 5721
5 tube sexyness

i guess im asking, "why choose staggared over overlapping or vise versa" because just like your pic above, those are overlapping but the demp pic has compression tubes in staggared? Whats the pros and cons of each?

EDIT: bypasses intrigue the hell out of me. there are so many ways to tune them or build them and im all about learning as much as i can on shocks. its amazing what properly tuned stuff will do on limited travel.
 
i guess im asking, "why choose staggared over overlapping or vise versa" because just like your pic above, those are overlapping but the demp pic has compression tubes in staggared? Whats the pros and cons of each?

EDIT: bypasses intrigue the hell out of me. there are so many ways to tune them or build them and im all about learning as much as i can on shocks. its amazing what properly tuned stuff will do on limited travel.
Always go for overlapping the tuning window is much greater, its all about flow if you don't have flow you will struggle to find a good compromise between good shaft speed and proper bump zone, staggered is early tech overlapping is new school, lots of flow potential is always better than limited flow potential, keep in mind tube size is also important a 3/4" tube will out flow a 1/2" tube. A good way to know if you have limited flow is if your tubes are wide open and it still feels harsh, normally you will have to pull valving from the piston to get rid of the harshness, when you do that you kill your bump zone, this is where the tuner and driver need to talk about going to a better shock package, B big boy 5 tube will have no compromise once set up to the vehicle, A staggered 3 tube will hit a tuning wall and you will need to decide what you want to go for speed or comfort
 
Always go for overlapping the tuning window is much greater, its all about flow if you don't have flow you will struggle to find a good compromise between good shaft speed and proper bump zone, staggered is early tech overlapping is new school, lots of flow potential is always better than limited flow potential, keep in mind tube size is also important a 3/4" tube will out flow a 1/2" tube. A good way to know if you have limited flow is if your tubes are wide open and it still feels harsh, normally you will have to pull valving from the piston to get rid of the harshness, when you do that you kill your bump zone, this is where the tuner and driver need to talk about going to a better shock package, B big boy 5 tube will have no compromise once set up to the vehicle, A staggered 3 tube will hit a tuning wall and you will need to decide what you want to go for speed or comfort

what about on a high motion ratio, short shock setup like you see now a days with toyotas and the new ford bronco? something in teh 1.75 to 2.0 to 1 motion ratio on an 8" stroke shock, any benefit going to a 5 tube or are they even able to fit it? i think a 5 tube would still work on a 10" stroke, right?
 
what about on a high motion ratio, short shock setup like you see now a days with toyotas and the new ford bronco? something in teh 1.75 to 2.0 to 1 motion ratio on an 8" stroke shock, any benefit going to a 5 tube or are they even able to fit it? i think a 5 tube would still work on a 10" stroke, right?
when getting down to a 8" stroke a 3 tube is plenty on a 2.5" diameter, 10" would see some gains from an additional rebound tube but packaging gets very tight, there are advantages to having the additional stages but packaging generally doesn't allow for more than 3 tubes on a taco or new gen bronco or most bolt on a arm kits, generally we don't start doing 5 tubes until 12". We did just do a set of 3 compression single rebound 3.0x10 for all of the compression flow potential this application has quite a bit of compression damping in it and we needed all of the flow to allow for a good shaft speeds down towards droop to ride height. The motion ratio only dictates the force your trying to control its a multiplier more force more valving. Being able to control when the valving takes effect is the magic of the bypass zones or stages.
 
So stoked you guys joined the forum.

Shock theory and chatter is just so helpful. I already spent a bunch of time reaching the spring theory today and well... I've never measured anything like that so I'll be doing that soon to see how far off I am.

 
So stoked you guys joined the forum.

Shock theory and chatter is just so helpful. I already spent a bunch of time reaching the spring theory today and well... I've never measured anything like that so I'll be doing that soon to see how far off I am.

Happy to help any way we can!
 
Here is an example of Lots of tubes on a shorter bypass.
Juicy…
 

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I have a spring under kit on the rear of my Tacoma , running 2.5x16” 3 tube bypass Kings. I had them “tuned” and I was set up with the rebound side shims at all 8. Which was a great improvement. However the compression shims set at all 15 with the largest shim doubled up. Wondering why they would have set up the compression like that? My thoughts were to prevent body roll? Definitely much more harsh on the smaller bumps
 
I have a spring under kit on the rear of my Tacoma , running 2.5x16” 3 tube bypass Kings. I had them “tuned” and I was set up with the rebound side shims at all 8. Which was a great improvement. However the compression shims set at all 15 with the largest shim doubled up. Wondering why they would have set up the compression like that? My thoughts were to prevent body roll? Definitely much more harsh on the smaller bumps
Throw a small diameter .008 between the two largest shims and see how that handles the chatter/small bumps
 
Throw a small diameter .008 between the two largest shims and see how that handles the chatter/small bumps
that will kill the bump zone of the bypass i would not recommended that just yet, i would hate to see him start bottoming out as a compromise for chatter compliance without knowing where the tube adjustments are
I have a spring under kit on the rear of my Tacoma , running 2.5x16” 3 tube bypass Kings. I had them “tuned” and I was set up with the rebound side shims at all 8. Which was a great improvement. However the compression shims set at all 15 with the largest shim doubled up. Wondering why they would have set up the compression like that? My thoughts were to prevent body roll? Definitely much more harsh on the smaller bumps
the theory behind what they did was to give you a stronger bump zone possibly for additional weight you may have i dont dissagree with this setup, I'm assuming you have smaller prerunner tubes on this set of shocks, the harshness comes from lack of flow on the small tubes, if your lower tube is not fully open or nearly there you may want to start opening it up this will allow more flow near ride height which should kill some of your chatter, the upper tube will be your transition zone from ride height to the bump zone, the trick is balancing a good bump zone with good flow in the lower zones that is why modern performance bypasses will have overlapping tubes of a larger diameter for more flow, How do your tube adjustments look right now?
 
that will kill the bump zone of the bypass i would not recommended that just yet, i would hate to see him start bottoming out as a compromise for chatter compliance without knowing where the tube adjustments are

the theory behind what they did was to give you a stronger bump zone possibly for additional weight you may have i dont dissagree with this setup, I'm assuming you have smaller prerunner tubes on this set of shocks, the harshness comes from lack of flow on the small tubes, if your lower tube is not fully open or nearly there you may want to start opening it up this will allow more flow near ride height which should kill some of your chatter, the upper tube will be your transition zone from ride height to the bump zone, the trick is balancing a good bump zone with good flow in the lower zones that is why modern performance bypasses will have overlapping tubes of a larger diameter for more flow, How do your tube adjustments look right now?
This makes sense as I have noticed during harder hits / jumps that the bump zone was more pronounced and needed to drop the hydro bump pressure so it wasn’t doubling up with the bump zone in the bypass. For weight in the back, two spares, battery, full set of tools/impact, oils, spare parts, jack and usually a cooler. I do have the smaller tubes and it is a staggered tube layout.
Tubes right now from fully open
First tube : 2.5 turns
Second tube: 4.5 turns
Rebound: 3 turns
2” hydro bump: 85psi
 
This makes sense as I have noticed during harder hits / jumps that the bump zone was more pronounced and needed to drop the hydro bump pressure so it wasn’t doubling up with the bump zone in the bypass. For weight in the back, two spares, battery, full set of tools/impact, oils, spare parts, jack and usually a cooler. I do have the smaller tubes and it is a staggered tube layout.
Tubes right now from fully open
First tube : 2.5 turns
Second tube: 4.5 turns
Rebound: 3 turns
2” hydro bump: 85psi
if it was my truck i would blow that lower compression tube wide open and work on the short tube to get the transition smooth between the zones, if you find that its blowing thru the travel to easily then you may need to close it back some but i doubt it, that will be about everything you can get out of the staggered small tubes, if the rear is not rising or acting funny after that you may be able to get that rebound open as well, both of these will help get rid of the chatter and not kill your bump zone.
 
Sounds good I’ll give it a shot! Thanks for the help! I should really go to a larger overlapping tube layout. But then again I should also just link it. Future plans hopefully
 
Sounds good I’ll give it a shot! Thanks for the help! I should really go to a larger overlapping tube layout. But then again I should also just link it. Future plans hopefully
well if you get a good layout you can always use it when you link it later ;)
 
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