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Discussion Starter #1
My front shocks should finally be here any day so I can finish my shock towers. I’m not sure how much if any shaft I should have showing at full bump. The shocks are slightly farther out on the axle than the bumps, so at full articulation assuming the Jeep is heavy enough to fully compress the bump it would bottom the shock. My question is should the shock bottom at the same time as the bump when the axle is at full bump on a horizontal plane, or should the shock bottom at the same time as the bump at full articulation? Obviously if it bottoms at full articulation I will loose some usable travel in the go fast stuff.


Specs
2006 LJ
4600 legal Ultra4
12” x 2.5” Kings
2”x2” King Bumps




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Rolling Mod
04 Wrangler Unlimited, 67 F100
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If your shocks bottom at the same time as the bumps with the geometry shown, your shocks will bottom out before the bumps on articulation. Given that geometry you probably want a half inch to an inch of shaft showing at full bump. Ideally you will articulate the axle before welding in the bump stops and shock mounts.
 

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"I was told" to leave a inch of shaft on the shock when the bumps are bottomed out in the horizontal plane, that way you won't bottom the shock in articulation.

the bump stock in articulation acts as a pivot point, assuming you won't hit full articulation at substantial speed, it isn't *that* big of a deal to bottom the shock eventually, as it will eventually reach the bottom anyways. if you are on the limit strap on the low side, the bump stop on the high side, the axle can only move until the shock itself is bottomed and then will lift the whole rig
 

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678 Posts
Your bump stops may never make any contact when you're in full one wheel bump (articulation).

Ryan at Accutune had me set up the shocks with one inch of shaft showing at full two wheel bump (Horizontal, when the bump stops would stop movement).

During full one wheel bump (articulation), the axle will continue up until the shock bottoms out on it's little rubber bump stopish thing on the shaft.

On my setup, which isn't much different than your picture, the axle never makes any contact with the bump stops during articulation, even though the side that's compressing travels another 2.5" up (at the wheel).
 

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Your ...l).
since this is a smaller thread with more folks here, mind iffn' I toss a question out to the group? I only quoted yall in the event you have "quote notifications" on while I try to make a complete thought. anybody else, feel free to chime in also :rasta:

shock angle and eye travel. probably beat to death, but damn I can't find much threads. guess that means it doesn't much matter :rasta:

my lower link are 42" eye to eye and my axle mounts are 42" eye to eye. with a 14" shock set to 7" up/down, lower links are // to the ground at rest and axle is (hopefully) // at rest as well.

according to triangle rules, 7" of travel equates to just under 10* and with a hypotenuse of 42, I get a same side of 41.5" (about).

in theory, that means to me that my lower shock eye, relative to my upper shock eye, will only move around in about a 1/2" square during travel. i.e. full bump or droop, 1/2" back and full articulation, 1/2" inboard. additionally, it should only travel that 10* as it goes in and out, up and down.

lower shock eye mounts are set square to the axle, so 'at rest' that eye should be about 10* (if we ignore pinion roll)

at full stuff, lower shock eye would then be square and at full droop lower shock eye would be 20* <<<-----does that compute?

should the upper shock eye be set about the same angle? i.e. square to the shaft (centered in travel of joint) at full stuff, ending at 20* full droop.

or, should it be set opposite, i.e. 20* at full stuff, then going towards 0* (90*) at full droop?

follow on, anybody know how much travel a 1/2" spherical end has?
 

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Old School
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If possible, outboard the bump stops so they are inline front-to-rear with the lower coilover tab. The closer you get, the smaller the compromise you need to make. This is how mine are set up:
 

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blah blah blah....too much talky, not enough pictures
so i got a chance to do some (many) drawings and some measuring. thinking this is starting to make sense

shock angle.jpg

drawing is to scale, one bolded line equals 4.91", each small grid line is just under 1" :rasta:

coming from the left, i have 3 lines representing the lower link, max up, neutral, max down.

along the top, i have a neutral reference line. coming down from that i have 3 lines representing the shock body. max up, neutral, max down representing a 14" travel shock.

angles along the top represent the angle of the top shock eye to my neutral line (in my case, this is actually my top hood line) so 100* represents 10* angled from 90*. 90* being neutral for the eye.

top eye should see only 5* worth of angle change through travel, with max deflection about 10*

angles to the left of the "shock" and to the "link" just to show the goal of 90* at to the link at full stuff, and then the relationship going on down. this is where i think i was confusing myself for a while.

angles to the right of the shock represent the angle to the lower shock mount on the axle housing. with my particular setup, i should have about 7* of pinion roll throughout travel, and reality seems to reflect that. i.e. with my shock angled back 10* to the earth, the joint is only seeing 5* of angle due to pinion roll. total change for the lower eye is only about 4*, with a max deflection around 9*


concerning the available angle in the eye: my unrestricted joint has a total travel of 35*, so 17.5* each direction

my lower eye in the very standard "shock tab" mounts only has ~25* (12.5* each side) of range before the shock body contacts the tabs. nothing a little grinder or big fucking hammer and torch can't finesse, for a touch of extra security.

i just hate a mount that binds a joint :shaking: something to keep in mind for the upper joints, might need to go with a wider misalignment spacer.

all that to say this: the joint has plenty of range of motion, just make the mounts easy and call it a day :flipoff2:
 
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