Correct.
Fair enough. Pictures would aid the discussion immensely, but my MS Paint skills aren't up to the challenge. I'll leave it for another day.
Why no Radius arm suspensions? (1 Viewer)
- Thread starter Tigerstripe40
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Correct.
Fair enough. Pictures would aid the discussion immensely, but my MS Paint skills aren't up to the challenge. I'll leave it for another day.
Radius arm
You can see that the link is only attatched to the frame at a single point. But fully captures the axle and stopps it from being twisted. Arms are identical on both sides. A panhard bar is also necessary to locate the axle laterally.
"Wristed" Radius arm
The arms are basically the same as the above units but one side (typically the side without the DS) can rotate. During articulation the axle needs to have some sort of differential between the left and right side or binding occurs. the "wristed" side solves this issue. It also adds a bunch of complications due to odd torque shifting and some fairly interesting braking habits. It is not the same a removing a sway bar. The effects are considerably more noticable.
Three links are a bit more complex. mostly because there are multiple types...
A typical three link has a single link on one side (typically the opposite side of the DS) and two seperate links on the other side. My FJ40 front suspension is a 3 link with a panhard bar to locate the axle laterally.
Passenger side
Driver side.
You can also have a "wishbone" threee link. Which will get confusing becasue the wishbone section can be mounted with the 2 legs on the axle or on the frame. And then there are two more links associated with it. So it may "look" like a 4 link, but it really is not. The wishbone is a single link, it just potentialy has multiple frame attachment points. A wishbone 3 link does not need a panhard bar.
4 links have a buncha variables. There are a multitude of ways to set them up. Parallel links with a panhard,
one set of the links is traingulated,
both sets of links are triangulated.
All suspension designs have some sort of give and take. It is the best idea to balance what you need Vs, what you can do.
You can see that the link is only attatched to the frame at a single point. But fully captures the axle and stopps it from being twisted. Arms are identical on both sides. A panhard bar is also necessary to locate the axle laterally.
"Wristed" Radius arm
The arms are basically the same as the above units but one side (typically the side without the DS) can rotate. During articulation the axle needs to have some sort of differential between the left and right side or binding occurs. the "wristed" side solves this issue. It also adds a bunch of complications due to odd torque shifting and some fairly interesting braking habits. It is not the same a removing a sway bar. The effects are considerably more noticable.
Three links are a bit more complex. mostly because there are multiple types...
A typical three link has a single link on one side (typically the opposite side of the DS) and two seperate links on the other side. My FJ40 front suspension is a 3 link with a panhard bar to locate the axle laterally.
Passenger side
Driver side.
You can also have a "wishbone" threee link. Which will get confusing becasue the wishbone section can be mounted with the 2 legs on the axle or on the frame. And then there are two more links associated with it. So it may "look" like a 4 link, but it really is not. The wishbone is a single link, it just potentialy has multiple frame attachment points. A wishbone 3 link does not need a panhard bar.
4 links have a buncha variables. There are a multitude of ways to set them up. Parallel links with a panhard,
one set of the links is traingulated,
both sets of links are triangulated.
All suspension designs have some sort of give and take. It is the best idea to balance what you need Vs, what you can do.
BTW, there is also a 1 link commonly called a graderball suspension.
It is made up of a wishbone like the 3 link but the legs of the wishbone are firmly welded to the axle. The only movement is at the single frame point.
They is kinda ghetto
It is made up of a wishbone like the 3 link but the legs of the wishbone are firmly welded to the axle. The only movement is at the single frame point.
They is kinda ghetto
There is an alternative improvement on the Radius arm (not panhard) developed by an Australian engineering firm know as a X-link.
This removed the front bolts on a traditional radius arm set up and attaches to a beam across that is pivoted on the front of the axle it the centre. This removes the inherant radius arm bind. Check out the link below.
http://www.dobbinengineering.com/index.htm
This removed the front bolts on a traditional radius arm set up and attaches to a beam across that is pivoted on the front of the axle it the centre. This removes the inherant radius arm bind. Check out the link below.
http://www.dobbinengineering.com/index.htm
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Eskimo
SILVER Star
That would last all of 5 minutes on a trail here... but a neat idea!
Interesting design.. I like it. I bet it would last longer than you would think Eskimo..
As long as it was built heavy duty..
But one question.. How does it replace the panhard?
As long as it was built heavy duty..
But one question.. How does it replace the panhard?
No doesn't replace pan hard that i know of.
The chap that has come up with this has developed some pretty amazing trucks and systems, particularly completly adjustable air ram over coilover systems.
I suspect anything he builds would last well. This is one of his vehicles.
I have seen some pictures of this setup on a 80 series, and they achieve some pretty good travel
The chap that has come up with this has developed some pretty amazing trucks and systems, particularly completly adjustable air ram over coilover systems.
I suspect anything he builds would last well. This is one of his vehicles.
I have seen some pictures of this setup on a 80 series, and they achieve some pretty good travel
just asking a simple question....but a four link as pictured above (or the rear suspension on a 80 for example) isn't it actually a 5 link? you have the 4 control arms, and then the track bar.....so wouldn't the track bar be considered a link?
Tapage
Club 4X4 Panamá
In the rear of 80 series I thought you have a 4 link + panhard.
Eskimo
SILVER Star
You're correct, but the panhard usually isn't included when talking about it like that, I suppose since it's purpose is to locate the axle side to side only.
a 3-link would otherwise be called a 4-link, a 4-link a 5-link, and a triangulated 4-link still a 4-link. THAT would be confusing as hell..
edit: didn't see Mace's post.
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This is what I was referring to in my original post - that folks here in the US with radius arm 80-series would build up their trucks to run 36"-40" tires and have access to a multitude of talented off-road suspension fabricators that could do a 3-link on these in their sleep and be completely convinced that it would ruin their truck. It's also interesting because the cost of doing a 3-link on the front of an 80-series is no where near what it would be to import one of those x-links and for a DIY'r it's still less than buying the custom radius arms from Slee (and I have nothing but positive thoughts on Slee and his products).
But I'm still a bit miffed about why you could spend under $500 on materials and have a very functional 3-link front on an 80, do the tiny amount of extra work of retaining the springs top and bottom and modifying the shock towers to run the full compression/extension of good 14" travel shocks and still be told that it's just a ramp queen and all that flex doesn't translate to real seat of the pants performance on a trail. Or that the front will be so floppy you'll death roll it on the road on the way to the trail. A lot of this seems to come from folks with a lot of Jeep experience modifying the front coil-spring suspensions to get lots of wheel travel.
I sure don't have it all figured out but I've got the rear set up as balanced as I ever hope to with the static ride height showing 7" of exposed shaft on a set of Bilstein 7100 14" travel shocks and when cycled the shock maxes out just as the control arms are binding against the mounts and the opposing tire is stuffed with that side shock within 1/2" or less fully compressed. I've also got the rear panhard on a custom mount so it as close to horizontal (level with plane of axle) at static ride height as well. With that done I'm sitting on the 3-link stuff on the garage floor ready to start plasma cutting and wondering if it's a dumb exercise in experiential learning....
But I'm still a bit miffed about why you could spend under $500 on materials and have a very functional 3-link front on an 80, do the tiny amount of extra work of retaining the springs top and bottom and modifying the shock towers to run the full compression/extension of good 14" travel shocks and still be told that it's just a ramp queen and all that flex doesn't translate to real seat of the pants performance on a trail. Or that the front will be so floppy you'll death roll it on the road on the way to the trail. A lot of this seems to come from folks with a lot of Jeep experience modifying the front coil-spring suspensions to get lots of wheel travel.
I sure don't have it all figured out but I've got the rear set up as balanced as I ever hope to with the static ride height showing 7" of exposed shaft on a set of Bilstein 7100 14" travel shocks and when cycled the shock maxes out just as the control arms are binding against the mounts and the opposing tire is stuffed with that side shock within 1/2" or less fully compressed. I've also got the rear panhard on a custom mount so it as close to horizontal (level with plane of axle) at static ride height as well. With that done I'm sitting on the 3-link stuff on the garage floor ready to start plasma cutting and wondering if it's a dumb exercise in experiential learning....
https://forum.ih8mud.com/showpost.php?p=2319294&postcount=51
well, now on to road testing to see how good the design was...
well, now on to road testing to see how good the design was...
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Thought that I'd pull this back up since it's been a few years. I'm currently exploring options for my 40's front. Anybody try these yet?
http://www.battlementfab.com/Radius-Arm-Kit_p_8.html
http://www.battlementfab.com/Radius-Arm-Kit_p_8.html
I had my coils unretained and half retained in the past. I find having both ends captured is far and away the best set up. It doesnt flex as much as uncaptured, but is far more controllable and less floppy.
and no one likes floppy.
Bronco drivers have been dealing with radius arms for decades. While there might be some that argue for them, i've seen a lot of discussion about how to get them to work and how to get rid of them.
