tri 4 link Q

[4sum4]

with a trianglated 4 link with uppers and lowers do only either upper or lowers need to be 40 deg,I can only get the lowers 40deg and the uppers i can get about 35deg

[Bush65]

The links that converge at the axle end are the ones which have to resist the side loads. Generally these will be the upper links. The more angle the less load in the link and mounts.

Assuming the lowers converge at the chassis end, the angle determines where they converge. The height of this point (relative to the point where the uppers converge) determines the roll axis.

[badger]

http://www.4wheeloffroad.com/techarticl ... on_part_2/

that link has heaps of infor on how u can change length n angle to have same effect

[redzook]

The links that converge at the axle end are the ones which have to resist the side loads. Generally these will be the upper links. The more angle the less load in the link and mounts.

i call BS

[hokey]

with a trianglated 4 link with uppers and lowers do only either upper or lowers need to be 40 deg,I can only get the lowers 40deg and the uppers i can get about 35deg

A bit of a noob question here, is that 40 deg the minimum angle that it needs to be triangulated to be able to locate the axle laterally like a panhard? if anyone understood that
Cheers, Calvin

[Bush65]

The links that converge at the axle end are the ones which have to resist the side loads. Generally these will be the upper links. The more angle the less load in the link and mounts.

i call BS

How about backing that statement up.

Are you saying that triangulated uppers, which converge at the axle end don't resist side loads? Then you are very wrong!

Are you saying that triangulated lowers, which converge at the chassis end, resist the side loads? Then you are still wrong!

[Guy]

I cannot see the difference between which set of links is trinagulated.. if the distance from the diff to the mount points is constant (Which it is as the arms are solid) Then the longer "angled" links will cannot allow side to side movement.

Please explain how I am wrong ... One may be better than the other (uppers triangulated better than lowers or otherway around).

[redzook]

The links that converge at the axle end are the ones which have to resist the side loads. Generally these will be the upper links. The more angle the less load in the link and mounts.

i call BS

How about backing that statement up.

Are you saying that triangulated uppers, which converge at the axle end don't resist side loads? Then you are very wrong!

Are you saying that triangulated lowers, which converge at the chassis end, resist the side loads? Then you are still wrong!

so ur telling me triangulated lowers converging at the frame end and parrallel uppers wont work?

http://www.pirate4x4.com/forum/attachme ... 1120703674

are the uppers controlling the side load here?
there is nothing converging at the diff end so there is nothing controlling side loads in your book?

edit: link dosent work so i attached the pic

[Bush65]

The links that converge at the axle end are the ones which have to resist the side loads. Generally these will be the upper links. The more angle the less load in the link and mounts.

i call BS

How about backing that statement up.

Are you saying that triangulated uppers, which converge at the axle end don't resist side loads? Then you are very wrong!

Are you saying that triangulated lowers, which converge at the chassis end, resist the side loads? Then you are still wrong!

so ur telling me triangulated lowers converging at the frame end and parrallel uppers wont work?

http://www.pirate4x4.com/forum/attachme ... 1120703674

are the uppers controlling the side load here?
there is nothing converging at the diff end so there is nothing controlling side loads in your book?

You haven't been able to back up you statement, that what I said was BS.

[GRIMACE]

The links that converge at the axle end are the ones which have to resist the side loads. Generally these will be the upper links. The more angle the less load in the link and mounts.

i call BS

How about backing that statement up.

Are you saying that triangulated uppers, which converge at the axle end don't resist side loads? Then you are very wrong!

Are you saying that triangulated lowers, which converge at the chassis end, resist the side loads? Then you are still wrong!

so ur telling me triangulated lowers converging at the frame end and parrallel uppers wont work?

http://www.pirate4x4.com/forum/attachme ... 1120703674

are the uppers controlling the side load here?
there is nothing converging at the diff end so there is nothing controlling side loads in your book?

You haven't been able to back up you statement, that what I said was BS.

well said...

I dont have much triangulation (only about 30 odd degrees) on my rear 4 link but so far it seems rather sturdy... time will tell

[redzook]

The links that converge at the axle end are the ones which have to resist the side loads. Generally these will be the upper links. The more angle the less load in the link and mounts.

i call BS

Are you saying that triangulated lowers, which converge at the chassis end, resist the side loads? Then you are still wrong!

so of the picture i posted which links are controlling the side load?

[GRIMACE]

The links that converge at the axle end are the ones which have to resist the side loads. Generally these will be the upper links. The more angle the less load in the link and mounts.

i call BS

Are you saying that triangulated lowers, which converge at the chassis end, resist the side loads? Then you are still wrong!

so of the picture i posted which links are controlling the side load?

[beebee]

That's pics got me thinking.... Would that setup actually work? As I see it, any side load cause opposing rotational forces in the axle tubes AKA Chinese burn style. Surely that wouldn't hold up in an abused heavy weight rig?


EDIT: I've thought a little more about it and it would probably be ok but I don't see any advantage over triangulated uppers....

Any other opinions?

[PJ.zook]

http://www.4wheeloffroad.com/techarticl ... on_part_2/

that link has heaps of infor on how u can change length n angle to have same effect

That is a brilliant site man, im glad i saw it before i started my 4 link, my design wouldve worked i think but now i know how it should be done im changing some bits.

[redzook]

That's pics got me thinking.... Would that setup actually work? As I see it, any side load cause opposing rotational forces in the axle tubes AKA Chinese burn style. Surely that wouldn't hold up in an abused heavy weight rig?


EDIT: I've thought a little more about it and it would probably be ok but I don't see any advantage over triangulated uppers....

Any other opinions?

a fair few people run it on pirate i think DSI and some one else were the first people to run it i think it was in DSI's comp rig?

nearly all the setups tho seem to run very high AS

i cant see the difference between that and a traditional IVI setup! so it should hold up aswell as them

[4sum4]

were or how do you get the roll axis point for the rear?

[redzook]

were or how do you get the roll axis point for the rear?

Assuming the lowers converge at the chassis end, the angle determines where they converge. The height of this point (relative to the point where the uppers converge) determines the roll axis.

or are u talking about the picture i posted?

[A1]

look here

[4sum4]

were or how do you get the roll axis point for the rear?

Assuming the lowers converge at the chassis end, the angle determines where they converge. The height of this point (relative to the point where the uppers converge) determines the roll axis.

or are u talking about the picture i posted?

yeah the pic you posted

[redzook]

were or how do you get the roll axis point for the rear?

Assuming the lowers converge at the chassis end, the angle determines where they converge. The height of this point (relative to the point where the uppers converge) determines the roll axis.

or are u talking about the picture i posted?

yeah the pic you posted

i dont know for sure but i am guessing the angle of the upperlinks when viewed from thew side

i am assuming thats why nearly every one running that setup has such high anti squat! they run flat uppers to try to get a flat roll axis therefore giving them a heap of AS

[Bush65]

were or how do you get the roll axis point for the rear?

Assuming the lowers converge at the chassis end, the angle determines where they converge. The height of this point (relative to the point where the uppers converge) determines the roll axis.

or are u talking about the picture i posted?

yeah the pic you posted

i dont know for sure but i am guessing the angle of the upperlinks when viewed from thew side

i am assuming thats why nearly every one running that setup has such high anti squat! they run flat uppers to try to get a flat roll axis therefore giving them a heap of AS

The roll axis will pass through the point where the triangulated links converge, and will be parallel with the links that are parallel when looking from above.

A flat roll axis does not have anything to do with having a heap of anti-squat.

[Bush65]

The links that converge at the axle end are the ones which have to resist the side loads. Generally these will be the upper links. The more angle the less load in the link and mounts.

i call BS

How about backing that statement up.

Are you saying that triangulated uppers, which converge at the axle end don't resist side loads? Then you are very wrong!

Are you saying that triangulated lowers, which converge at the chassis end, resist the side loads? Then you are still wrong!

so ur telling me triangulated lowers converging at the frame end and parrallel uppers wont work?

http://www.pirate4x4.com/forum/attachme ... 1120703674

are the uppers controlling the side load here?
there is nothing converging at the diff end so there is nothing controlling side loads in your book?

edit: link dosent work so i attached the pic

In your pic, the triangulated lowers will resist the side load.

What I said, and what you highlighted in red and called BS was:

The links that converge at the axle end are the ones which have to resist the side loads...

Now you still haven't backed up your statement calling this BS. The fact is that you can not

[redzook]

In your pic, the triangulated lowers will resist the side load.

What I said, and what you highlighted in red and called BS was:

The links that converge at the axle end are the ones which have to resist the side loads...

Now you still haven't backed up your statement calling this BS. The fact is that you can not

so u have addmitted that the lower links are the ones controlling the side load? converging at the chassis end

so as soon as u triangulate the uppers at the diff end, the lowers converging at the chassis end just automatically become unable to resist side load?

i dont know anyother WAY to say it

BOTH the upper and lower links in a tri 4link will resist the side load

therefore your stament of "The links that converge at the axle end are the ones which have to resist the side loads" not tru as both the ones that converge at the diff end and the chassis help resist the sideload

[redzook]

i dont know for sure but i am guessing the angle of the upperlinks when viewed from thew side

i am assuming thats why nearly every one running that setup has such high anti squat! they run flat uppers to try to get a flat roll axis therefore giving them a heap of AS

The roll axis will pass through the point where the triangulated links converge, and will be parallel with the links that are parallel when looking from above.

A flat roll axis does not have anything to do with having a heap of anti-squat.

i know the AS and axis have nothing to do with each other

but to get low AS on a setup like that with a flat roll axis
would basically have to be in a moon buggy or somthing with very flat lower links (close to parrallel to the ground)

[redzook]

Are you saying that triangulated lowers, which converge at the chassis end, resist the side loads? Then you are still wrong!

In your pic, the triangulated lowers will resist the side load.

SORRY i just had to put these together

[red90]

The reason for having the uppers converge at the axle is that this height set the roll center. A higher roll center produces less body roll when turning and off camber. For lightly sprung rigs, this is very helpful.

With triangulation only at the chassis, side loading creates forces in all of the links and can cause suspension movement in of itself.

[Bush65]

In your pic, the triangulated lowers will resist the side load.

What I said, and what you highlighted in red and called BS was:

The links that converge at the axle end are the ones which have to resist the side loads...

Now you still haven't backed up your statement calling this BS. The fact is that you can not

so u have addmitted that the lower links are the ones controlling the side load? converging at the chassis end

Not when the uppers converge at the axle. But it appears that you don't know enough to understand that simple fact, you can not prove otherwise, yet you call BS.

In the 1st post 4sum4 was asking about angles of triangulated uppers and lowers. Not triangulated lowers an parallel uppers.

so as soon as u triangulate the uppers at the diff end, the lowers converging at the chassis end just automatically become unable to resist side load?

Correct!

i dont know anyother WAY to say it

BOTH the upper and lower links in a tri 4link will resist the side load

Wrong! If the uppers and lowers all resist side load, and they are separated vertically at the axle, then the axle could not articulate .

therefore your stament of "The links that converge at the axle end are the ones which have to resist the side loads" not tru as both the ones that converge at the diff end and the chassis help resist the sideload

My statement was correct. Yours is incorrect.

I will give a procedure that anyone should be able understand and test.

Take a triangulated 4 link, with uppers converging at the axle and lowers converging at the chassis. Remove the springs, shocks and wheels, so that they do not resist axle articulation. Suspend it so the axle is high off the ground.

Mark points on the ground, directly below the axle ends of the upper and lower links.

Now push the axle so that it articulates. If the joints at the ends of the links, or the links themselves, do not bind, the axle will swing easily (except for out of balance weight of the axle). In cases where the axle was not restricted by the chassis, and the joints at the links allow, the axle could rotate nearly 90 deg.

It will be clear (even to blind freddy), that the axle rotates about a point near where the uppers converge (the roll centre). The ends of the uppers hardly move to the side. But the lowers, which attach to near the outer ends of the axle, move considerably to the side as the axle articulate.

When the uppers converge at the axle, the axle end of the lowers could not move to the side, if as you claim, the lowers resist the side load.

Sorry to hijack your thread 4sum4. redzook calls BS, but can't back it up. This thread should go back to what it was about.

hijack off.

[GRIMACE]

i am lost.... all links are working together to keep the diff located under the rig... thats my simple way of putting it...

[Guy]

i am lost.... all links are working together to keep the diff located under the rig... thats my simple way of putting it...

Thats what I thought ...

I think what has been said is along with some chest beating is so long as the links are triangulated they will locate the diff under the vehicle (with varying degress of sucess)

["CANADA"]

3 Link pan' would have saved this long winded thread