Yet ANOTHER anti-wrap bar question...

[miker]

Single link bars in general do not work properly and end up breaking because by design, they can not deal with articulation. They work great in a "straight up and down" application. But when articulation comes into play, they quickly reach their mechanical limits.

Hey Georg, I'm interested in knowing more here on where the articulation will break a single link type bar? For the ones that you've seen break, what sort of mounts were they using at each end? Did they allow for twist to follow the axle?

Obviously, with a single link bar, it needs to be able to freely follow the axle as it articulates. If not, it will surely break.

This is actually the type I've been using for years. I've also installed them on several other FJ40's and as far as I know, no breakage, at least none reported to me. They are not faultless in design and actually force small pinion angle changes as the axle moves up and down, but they also help limit the axle rotation which causes the ujoint and pinion breakage. But, a single bar relies on the leaf spring to complete the triangulation and therefore it is a weakness in the design, but they definitely work much better than no bar at all.

If you really like the skinny pedal then the single bar type is probably not a good chioce for you as you are likely to still twist up the springs over time. Very soft springs will also tend to make this type less effective since again, the spring is part of the anti-rotation equation.

Basically, I've had good luck with them and will continue to use them. They are simple to make, cheap, and they don't require massive wall tube.

Slso, I believe that there is less "forced" rotation induced with suspention travel with the single bar vs. the triangle bar type. But again, if you have a heavy foot, I've vote for the triangle type. The Single tube type works well with my driving style...the skinny pedal scares me.

 

[Weber Sarge]

Pics of the bar in the same 40.

That's basically the same design as Breeze minus the sliding tube front piece where yours uses a shackle w/bushings . I always wanted to source rubber bushings to replace the very hard poly units Breeze had used-that alone may have stopped the nasty shockloads to the driveline .

Here's the original Breeze bar setup -



The idea that the sliding tube front can allow the bar to rotate really helped with articulation . Down side is keeping it greased as it did get stuck a few times despite having a seal . I like Georg's idea of the bushings at the rear , helps stop shock loads if nothing else ....?

Just how far will that design twist ?
Sarge

 

[orangefj45]

back to basics for a minute.......

any suspension system requires compromises. you just have to find the combination that suits your needs. want great ride comfort? then go for springs and bushings. they'll ride nice but will give you the least control. want more control, then you go with a link suspension and more "fixed" ends like heim joints or johnny joints. major draw-back there is ride comfort. the more solid a suspension system is, the more it'll transfer every little movement and bump in the road thru the chassis.
in other words, for a multi-purpose vehicle that gets driven on the street, you want springs ( leafs or coils ) and bushings. for a dedicated competition style vehicle ( be it on-road or off-road ), you want link suspensions and heims or the likes.

track bars are an attempt to prevent axle wrap. it's pretty much part of a link suspension integrated into a spring type suspension. again, a compromise. in one way or another, you're going to limit the spring movement by introducing a link. does'nt matter if it's a single link, a triangle or whatever.

everybody agree with this?

georg

 

[cruiserland]

no

track bars are panhard bars, keep axle aligned side to side;ie track
anti wrap bars keep axle from wrapping,racecar guys call them traction bars as they keep they rear from hopping on the track,

semantics aside, you basically are right tho
track, traction, and antiwrap bars are all links, just need to set them up correctly

how many proper link setups have two solid attachment points at one end? not many, radius arm type suspension, but they are a halfbreed
broncos and 80's front comes to mind, no wrap but limited, esp working angles, and oh yeah, springs, not really links either
this does not allow proper movement/travel

think of the front of your leaf springs as the two bottom links, ignore the back half of spring that limits it(limiting strap?), it is missing a top link....

take your top link off your three link and add it to your leaf setup.
Done.
not sayin leaves are best, just sayin

of course the real way not to break it is to stop ion the second bounce

 

[Tennessee80]

To revive a super old thread here, if I may...there is some good info in this thread on different people's designs for these track bars. I have a new to me 1974 40 that is SOA. It does not have an axle wrap bar on it. The PO says that he did the Rubicon trail in it 10 years ago. My question is, what type of wheeling necessitates an axle wrap bar on a rig, or is it just good peace of mind to have the truck built with one to prevent axle wrap on the trail, which is obviously a bad thing...

thanks,

Joel

 

[Fast Eddy]

I have a new to me 1974 40 that is SOA. It does not have an axle wrap bar on it. The PO says that he did the Rubicon trail in it 10 years ago. My question is, what type of wheeling necessitates an axle wrap bar on a rig?

The Rubicon Trail, now. It's a totally different beast now than it was 10 years ago.

back to basics for a minute.......

in one way or another, you're going to limit the spring movement by introducing a link. does'nt matter if it's a single link, a triangle or whatever.

everybody agree with this?

Still no. My anti-wrap design does not, in any way, limit my spring movement. It only prevents the extreme axle wrap that would cause the pinion to bind, then break. It allows a certain degree of axle wrap, but well within the specs of the u-joint.

I brought a little camera to get a video of it during Rubithon, but I never got around to it.

 

[Tools R Us]

We did the thing! Grabbed a radius arm from one of those 80 series station wagon thingies, flipped it upside down and stick it in. Works great.

 

[reddingcruiser]

Holy cow! I forgot how much fun this thread was until I had a chance to read it again.

After swapping over to 60 springs and shoving the rear axle back I decided to NOT run the anti-wrap bar. I've got 4 Rubicon trips with the current setup and no problems. I do have the Ruff Stuff long spring perches and HD spring plates, though.

I've never been one to use the skinny pedal to excess and I'm perfectly willing to drag out the winch line when I'm in a real bind

 

[Tennessee80]

So with stock 40 springs that sit relatively level with low arch, what's the chance I'll get axle wrap? Or is it the engine torque that moves the axle forwards under power? I've got a F.5.

Lol

 

[Fast Eddy]

Works great.

When you compress the rear suspension on both sides at the same time, it needs to travel straight upwards at the front. What happens then?

The answer to this rhetorical question is that something breaks.

Yours is better than most as far as droop. It might be ok in this scenario. Jack it all the way up to the top of the suspension travel from the bumper and see if you can unbolt it to test.

What about twist? What if you put it on an articulation ramp? I see bad things (tm) in your future.

 

[Mace]

100% you will get axle wrap..

 

[Tools R Us]

... I see bad things (tm) in your future.

Thanks for the fortune cookie!


It actually works well, the '80 bushings have a lot of room for movement. From mocking/setting it up.

It rides, wheels well, has been on a couple of week+ wheeling trips to Utah, Colorado, and a bunch locally, without any hint of an issue. Unfortunately, his wife is done riding in that no A/C, noisy thing, so he will be selling it and upgrading to an '80.

Don't have any flex pix from the back handy, but it flexes at least as well as the front.

 

[Tennessee80]

Nice!

 

[Stumpalama]

My set-up is very similar to the 80 series radius arm idea. It is the JK customs style single bar attached to the rear axle at two points with the Ruffstuff axle mount kit rotated to about 30*. No hop and no noticeable adverse impact on articulation. The only issue I've noticed is that it appears to be flexing the DOM skid plate spreader into the brake drum. I think I need to shorten the bar slightly or go with thicker DOM on the skid plate support.

 

[orangefj45]

The Rubicon Trail, now. It's a totally different beast now than it was 10 years ago.



Still no. My anti-wrap design does not, in any way, limit my spring movement. It only prevents the extreme axle wrap that would cause the pinion to bind, then break. It allows a certain degree of axle wrap, but well within the specs of the u-joint.

I brought a little camera to get a video of it during Rubithon, but I never got around to it.

Let's see you put some real horsepower and man-sized tires on that little cream puff and then watch your rubber band explode!

LMAO

 

[Tennessee80]

 

[Fast Eddy]

Let's see you put some real horsepower and man-sized tires on that little cream puff and then watch your rubber band explode!

Well, if water pipes from Home Depot hold up to 200 ft lbs * 80:1, how much stronger would the same design made out of some DOM tubing? Double? Then it would survive 400 ft lbs. Man enough?

I don't enforce the laws of physics, but I understand them.

 

[reddingcruiser]

Hmmmmmm....

Let's see you put some real horsepower and man-sized tires on that little cream puff and then watch your rubber band explode!

LMAO

Too funny!!!!

 

[Tennessee80]

OMG why did I revive this thread

 

[orangefj45]

OMG why did I revive this thread

Because it's always a comedy show!!!!!