Bump Stop Check Walk-Thru With Pics


jjvw

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The shock appears to have more travel left at full compression. I’ll confirm. ...
Then something else is stopping the suspension travel. Find it and decide if you want to move past it. If not, then your shocks are too short.


...And might add a 1” no matter what for a safety factor. (Is that crazy or over cautious)

That is needlessly cautious and only cripples the suspension. Make the shocks the final limit to up travel. Then extend the bumps enough to make the jounces do their job of slowing the last bit of travel.

Once I get the springs installed I’ll confirm ride height and travel distances

By now you should be seeing that the are several things going on at once in this balancing act. Your goal is ~50/50 shock travel at ride height.

Thanks. I think I’m almost there.

Keep at it! You are going through a process that will help set your build apart from many others.
 
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BlueChip

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Then something else is stopping the suspension travel. Find it and decide if you want to move past it. If not, then your shocks are too short.




That is needlessly cautious and only cripples the suspension. Make the shocks the final limit to up travel. Then extend the bumps enough to make the jounces do their job of slowing the last bit of travel.



By now you should be seeing that the are several things going on at once in this balancing act. Your goal is ~50/50 shock travel at ride height.



Keep at it! You are going through a process that will help set your build apart from many others.
I stopped the full stuff when it hit the rubber mini stop I could have kept jacking the axle higher crushing that soft rubber.
 

jjvw

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I stopped the full stuff when it hit the rubber mini stop I could have kept jacking the axle higher crushing that soft rubber.

That wasn't full stuff. That soft rubber is the jounce I keep mentioning. It is intended to crush into the cup. Full stuff/full bump is when either the shock reaches full compression or when the steel cup touches the axle pad.
 
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BlueChip

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That wasn't full stuff. That soft rubber is the jounce I keep mentioning. It is intended to crush into the cup.
Ok, that makes more sense then, thanks! I’ll crush that and relook. The tire will hit if that’s crushed. The pic below is when the jounce touches the pad.

So I’ll add a bump stop to where the jounce is crushed but not tire touch. I think I’m getting there haha slow learner
6D0838EE-93E1-4FDD-B634-A9AE7A81A066.jpeg
 

jjvw

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It's easier just to remove the jounce from the cup.

And don't let the flexible flare be your limit to up. If 50/50 shock travel has the tire lightly brushing against sheet metal, then let that happen.
 

Blackjack

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That wasn't full stuff. That soft rubber is the jounce I keep mentioning. It is intended to crush into the cup. Full stuff/full bump is when either the shock reaches full compression or when the steel cup touches the axle pad.
This. I do go a little on the conservative side and make the cup/axle pad my hard stop and leave a quarter inch or so of shock shaft showing.
 
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jjvw

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This. I do go a little on the conservative side and make the cup/axle pad my hard stop and leave a quarter inch or so of shock shaft showing.

Currie bumps don't really have a hard stop. They are just jounces. The shocks are the hard limit and all of its travel gets used.
 
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fuse

fuse

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Currie bumps don't really have a hard stop. They are just jounces. The shocks are the hard limit.
Bump stops made from hockey pucks don't really have a hard stop either. They can still compress a little when they hit the metal cup.

I aim to get full compression on the shock just when the metal cup contacts the bump stop. That way the jounce and the hockey puck are softening the blow when the shock gets to full compression.

But whether you're a little conservative like @Blackjack or try to squeeze every last bit of travel out like @jjvw, the idea is that the shock gets to full compression.
 
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Blackjack

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Currie bumps don't really have a hard stop. They are just jounces. The shocks are the hard limit and all of its travel gets used.
I understand what Currie is trying to do and one of these days I might have to play with them, I guess I am just part of the school that stops are supposed to do the stopping and not other parts of the system like the shocks.
 
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BlueChip

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Installing a Savvy 1.25 BL and MML this week , i assume i need to do this all over again right?

Any F / R Bump stop kits you recommend?
 
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fuse

fuse

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Installing a Savvy 1.25 BL and MML this week , i assume i need to do this all over again right?

Any F / R Bump stop kits you recommend?
I suppose it depends on why you're installing the BL. If the tires were rubbing before, you probably want to check to make sure they clear the fenders after the BL. And if you have some free stroke left on the shocks and clearance at the fenders, you could see if you could use smaller bump stops to use more of the travel.

As far a bump stop kits go, the most important thing is to get them the right length. As long as they're hard enough to limit axle movement and they clear the springs, pretty much anything is OK.

A lot of people just make their own. I'm pretty happy with my hockey pucks.

IMG_20190906_132527.jpg
 

BlueChip

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I suppose it depends on why you're installing the BL. If the tires were rubbing before, you probably want to check to make sure they clear the fenders after the BL. And if you have some free stroke left on the shocks and clearance at the fenders, you could see if you could use smaller bump stops to use more of the travel.

As far a bump stop kits go, the most important thing is to get them the right length. As long as they're hard enough to limit axle movement and they clear the springs, pretty much anything is OK.

A lot of people just make their own. I'm pretty happy with my hockey pucks.

View attachment 228674
BL/MML installed in the LJ to decrease the driveline angles. (Removed vibrations)

I think I will go the puck route. Should be able to dial it in close enough and prevent bottom out / rub.
Thanks

Chris
 
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GA05LJ

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This thread has been extremely useful as I have been trying to fine tune the axle placement on my LJ.
I just installed 4" Currie lift Springs with Savvy Double Adjustable control arms.

One question I have is around the wheels being centered in the wheel well at ride height (Front to Back). With a 4" lift it looks like there is no way around the rear axle swinging slightly forward and the front axle swinging slightly rearward (at Ride Height). Given the amount of folks on here running the 4" lift I would imaging others have ran into this issue. What is the common solution?

I'm at the point where I think I should jack it all up take the wheels off once again, remove the springs, and push the rear axle back to where the upper bumpstop cup is barely touching the front side of the axle pad. I had previously centered it on the axle pad. Then repeat this on the front?
 
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fuse

fuse

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This thread has been extremely useful as I have been trying to fine tune the axle placement on my LJ.
I just installed 4" Currie lift Springs with Savvy Double Adjustable control arms.

One question I have is around the wheels being centered in the wheel well at ride height (Front to Back). With a 4" lift it looks like there is no way around the rear axle swinging slightly forward and the front axle swinging slightly rearward (at Ride Height). Given the amount of folks on here running the 4" lift I would imaging others have ran into this issue. What is the common solution?

I'm at the point where I think I should jack it all up take the wheels off once again, remove the springs, and push the rear axle back to where the upper bumpstop cup is barely touching the front side of the axle pad. I had previously centered it on the axle pad. Then repeat this on the front?
I'm glad the thread is helpful, but this one is beyond me. Once you get to 4" there's a lot more going on with the build and the suspension setup and you might want to look at some other modifications to get everything to come out right.

I think a more detailed discussion about how to set up a 4" lift would be helpful. You might start a new thread in the general discussion where more people would see this. Or maybe @Chris would move the post there for you.
 

Chris

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This thread has been extremely useful as I have been trying to fine tune the axle placement on my LJ.
I just installed 4" Currie lift Springs with Savvy Double Adjustable control arms.

One question I have is around the wheels being centered in the wheel well at ride height (Front to Back). With a 4" lift it looks like there is no way around the rear axle swinging slightly forward and the front axle swinging slightly rearward (at Ride Height). Given the amount of folks on here running the 4" lift I would imaging others have ran into this issue. What is the common solution?

I'm at the point where I think I should jack it all up take the wheels off once again, remove the springs, and push the rear axle back to where the upper bumpstop cup is barely touching the front side of the axle pad. I had previously centered it on the axle pad. Then repeat this on the front?
I would create a new thread, your question is going to get lost in this thread.
 

jjvw

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I'm glad the thread is helpful, but this one is beyond me. Once you get to 4" there's a lot more going on with the build and the suspension setup and you might want to look at some other modifications to get everything to come out right.

I think a more detailed discussion about how to set up a 4" lift would be helpful. You might start a new thread in the general discussion where more people would see this. Or maybe @Chris would move the post there for you.

At the end of the day, the axles go where they fit and everything plays together well. Wheelbase is incidental.
 

Midtenn

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I cannot find anyone that sells 3” rear bump stops. Do I need to go adjustable? I’m running the 255/256 Rachos on a 4” lift w/ 33 inch tires. Looks to me I need about 3” of BS for the shock. Thanks to mods from the prior owner, I’m not hitting the fender so I’m only worried about shock.
 

jjvw

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I cannot find anyone that sells 3” rear bump stops. Do I need to go adjustable? I’m running the 255/256 Rachos on a 4” lift w/ 33 inch tires. Looks to me I need about 3” of BS for the shock. Thanks to mods from the prior owner, I’m not hitting the fender so I’m only worried about shock.
2x3" body lift pucks
 

JpZombie

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I cannot find anyone that sells 3” rear bump stops. Do I need to go adjustable? I’m running the 255/256 Rachos on a 4” lift w/ 33 inch tires. Looks to me I need about 3” of BS for the shock. Thanks to mods from the prior owner, I’m not hitting the fender so I’m only worried about shock.

A broken link was posted to this website for bump stops at some point in one of these threads. But looks like the address just changed for it.
 
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