how do adjustments compare

Cleandezert

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So I just revalved my rear bypasses and came up with a question i don't know the answer to. I was hoping a guru might....

So my bypass shocks needed more compression... the tubes were closed on compression already. I open up the shocks and I had a mix of .012 and .015 shims on compression, all bleeds open and my tubes closed. I closed 1 free bleed, upped my valving to a straight .015 stack, and opened up tubes so I could see how it worked and start closing them if needed.

so my question is this. Bleed screws, shims and bypass tubes. How do they compare when adding compression dampening?
Is adding a bleed screw the same as closing a bypass tube in half? is going from a .012 stack to a .015 stack the same as 4 turns on a comp tube? Is there any metrics to this? I was hoping answering this would help me understand my next move incase i need to add more valving again.
 
its not real black and white like that.

bleed holes are similar to how a bypass tube works accept they work in both direction (compression and rebound) where the tube only works in one direction unless you have a free bleed tube in place. Typically, you should be valving the piston valving for the bump zone and the tubes are for your ride control. So then you are adjusting poppets and springs in the tubes to get a nice ride. Thats why you hear/see guys liek barge saying to run just one free bleed open in the piston and run the piston valving heavy because it gives you all the bump control and makes the tubes do the work to soften up the ride. you cant say adding valving to a shim stack will increase X amount of tube turns because you can have different springs in tubes. its all variable

thats one way to go about it though. your ride height and piston to tube location is important, if you are running a hydro bump, if your running any valving in the coilover, and so on.
 
i totally understand all that. I was just curious as I looked at the shims I had available in my valving kit, and other parts, then it made me think... which is more effective. and i like to be able to go from a fully closed tube to a fully open one, to start adjusting again... and so the thought was, is adding this bleed similar to a fully closed tube? or is it 2 bleeds? (i only had 1 so it didn't matter at that time)

Currently, it's not a bottoming-out issue i have either. The truck just feels too loose in back, and needs some compression and now possibly some rebound added to keep it from lifting so much.
 
i totally understand all that. I was just curious as I looked at the shims I had available in my valving kit, and other parts, then it made me think... which is more effective. and i like to be able to go from a fully closed tube to a fully open one, to start adjusting again... and so the thought was, is adding this bleed similar to a fully closed tube? or is it 2 bleeds? (i only had 1 so it didn't matter at that time)

Currently, it's not a bottoming-out issue i have either. The truck just feels too loose in back, and needs some compression and now possibly some rebound added to keep it from lifting so much.
aaahhh then yeah you are looking at both the free bleeds and the valving just like you did but like i was saying, you wont get a direct corralation on "2 bleeds plugged is 8 turns of both tubes". seires or parallel tubes plays a part there too. its going to come down to you playing with it or talking with someone who has setup a truck similar to yours before.
 
they all do different things. piston bleed is not your friend in a bypass, the tubes should be what takes the edge off and allow you to have a progressive damping curve.

size of tubes, number of tubes, and layout will dictate how you approach valving a bypass.

i.e. you wouldnt valve a king prerunner bypass with small diameter tubes and stacked tube layout the same as a fox with larger tubes and an overlapping tube layout.
 
i totally understand all that. I was just curious as I looked at the shims I had available in my valving kit, and other parts, then it made me think... which is more effective. and i like to be able to go from a fully closed tube to a fully open one, to start adjusting again... and so the thought was, is adding this bleed similar to a fully closed tube? or is it 2 bleeds? (i only had 1 so it didn't matter at that time)

Currently, it's not a bottoming-out issue i have either. The truck just feels too loose in back, and needs some compression and now possibly some rebound added to keep it from lifting so much.
your dealing with a low speed control issue, plug your bleeds and start tuning from there the "free bleed" is literally that a free flowing "leak" add a bypass tube and you have tons of bleed which normally makes for a sloppy mess, what shock are you working with?
 
your dealing with a low speed control issue, plug your bleeds and start tuning from there the "free bleed" is literally that a free flowing "leak" add a bypass tube and you have tons of bleed which normally makes for a sloppy mess, what shock are you working with?
it felt like that. but was done for a reason due to past leaf spring set up and shocks riding in bumpzone at ride height. Now that is fixed its time to fix some valving to the new set up.
Truck is a 2011 f150 supercrew with spring under set up and a notched frame. 8" bump and 9" droop. King 3.0 4 tube 18" bypass. 2 compression 2 rebound tubes.
 
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