Link problems

[Rocfrog]

Ok so I have mad torque twist and my front upper 3 link mount keep pulling out so I decided to do some research on here. After some digging I figured I would just 4 link the rear with equal length uppers (because that's what I have) and just put the rear 3 link mount to the front. Well after making a new plate and all the back barely moves and has almost zero flex! Tell me what I did wrong!

Here's pics....








Nick

[Crawling Calvin]

Check your rod ends aren't to tight up against the chassis or your plate, that will cause heinous binding issues Other than that, try putting the links under the plate and/or try some washers. Remember most guys run their link plates now in a "U" shape with the links being attached like they are to your chassis, that means its less binding in the system.

[Grumpster1980]

X2 the links need to be free to move and need to be under the plate. You can also do one side over and the other under.

The best wat to reduce torque twist is to put a stiffer spring/spacer/pre-load or the left rear shock.

[flowingmotion]

It looks like in your setup as one of the rear wheels rise the link end will bind on the 4 link plate on the side the wheel is going up. you can trim the plate or put a spacer in there to raise it up. This will give you the space you need. If you just cycle the suspension with your hands you should be able to see the spot it's binding in.

Or you could do this...

duuuuuuuude's F4

[Rocfrog]

Originally Posted by Crawling Calvin

Check your rod ends aren't to tight up against the chassis or your plate, that will cause heinous binding issues Other than that, try putting the links under the plate and/or try some washers. Remember most guys run their link plates now in a "U" shape with the links being attached like they are to your chassis, that means its less binding in the system.

I checked and loosened the bolts holding the rod ends and still the same thing. I don't believe I have seen this "U" shape link set up....???

Originally Posted by Grumpster1980

X2 the links need to be free to move and need to be under the plate. You can also do one side over and the other under.

The best wat to reduce torque twist is to put a stiffer spring/spacer/pre-load or the left rear shock.

I can try moving one to the bottom, but I have read that keeping the driver rear on top will help with torque twist. So I just mounted both up top for a symmetrical look. As far as the spring/shock goes I'm trying to work with what I have and I have also read that that is just a temp fix.

Originally Posted by flowingmotion

It looks like in your setup as one of the rear wheels rise the link end will bind on the 4 link plate on the side the wheel is going up. you can trim the plate or put a spacer in there to raise it up. This will give you the space you need. If you just cycle the suspension with your hands you should be able to see the spot it's binding in.

Or you could do this...

duuuuuuuude's F4

I was thinking this but I think I'm cutting it close on the holes as is. Maybe I'll try a spacer. But the other problem I'm running into which is why the other set up you suggested wont work is this is where half of my battery usually sits, so even as it is now I need to figure out where/how to mount the battery.

see.....



So I'll try moving the one side to the bottom but I don't think it's going to make much of a difference. Are my links too long? they are the stock (I assume) lowers.....

Nick

[brushlessemaxx]

Originally Posted by Rocfrog

I checked and loosened the bolts holding the rod ends and still the same thing. I don't believe I have seen this "U" shape link set up....???



I can try moving one to the bottom, but I have read that keeping the driver rear on top will help with torque twist. So I just mounted both up top for a symmetrical look. As far as the spring/shock goes I'm trying to work with what I have and I have also read that that is just a temp fix.



I was thinking this but I think I'm cutting it close on the holes as is. Maybe I'll try a spacer. But the other problem I'm running into which is why the other set up you suggested wont work is this is where half of my battery usually sits, so even as it is now I need to figure out where/how to mount the battery.

see.....



So I'll try moving the one side to the bottom but I don't think it's going to make much of a difference. Are my links too long? they are the stock (I assume) lowers.....

Nick

Angles are all wrong, top is two long,, the upper links are two far apart.

[PhantomRS10]

my 3 link bar has popped out since i got the thing. i just put a washer on the axle side of the 3link and hasnt happend anymore since

[TOMCAT18T]

In this pic it looks as though you have little to no triangulation of your links. The first thing I would try is moving the axle end of your lower links to where your shocks are installed now, Then move the shock to the outside(closest to wheel) of the link mount.


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[gottorque]

This is rmdesignworks diagram of the actual science...yes science of torque twist and fighting it properly. From his T&T thread in the Creeper section
For thoes that say its as simple as adding a spacer and thicker oil in the left rear shock, its not. It is obtaining proper link geometry

Originally Posted by rmdesignworks

TECH TIP 4 & 5

Pics of how my VC is set up to help with Torque Twist. Specifically look at the rear axle and the rear upper link geometry.

[Duuuuuuuude]

Originally Posted by Grumpster1980

The best wat to reduce torque twist is to put a stiffer spring/spacer/pre-load or the left rear shock.

Thats the worst way to reduce it.

[Rocfrog]

Originally Posted by gottorque

This is rmdesignworks diagram of the actual science...yes science of torque twist and fighting it properly. From his T&T thread in the Creeper section
For thoes that say its as simple as adding a spacer and thicker oil in the left rear shock, its not. It is obtaining proper link geometry

Ok looking over these pic/diagrams I think I need to put a spacer on my link plate under the rod ends and move my shocks and links as you suggest.....

Ok I'll pull it all back apart tomorrow and try that. If that works I just have to figure out where to mount the other half of my battery....

Nick

[Terranaut]

Originally Posted by brushlessemaxx

Angles are all wrong, top is two long,, the upper links are two far apart.

I agree that the upper links are too far apart at the axle. Move them as close together as you can without them touching each other. I have mine on just one bolt right in the middle, with one link above the plate and one below. This gives good triangulation, and helps counter torque twist.

Originally Posted by TOMCAT18T

In this pic it looks as though you have little to no triangulation of your links. The first thing I would try is moving the axle end of your lower links to where your shocks are installed now, Then move the shock to the outside(closest to wheel) of the link mount.


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I'll second that movement, exactly as stated.

Once you have done both of these changes, disconnect the shocks at the top so you can play with the axle in your hands and look for any binding in the links. Fix that and you should be good to go.

Cheers.

[brushlessemaxx]

Originally Posted by Terranaut

I agree that the upper links are too far apart at the axle. Move them as close together as you can without them touching each other. I have mine on just one bolt right in the middle, with one link above the plate and one below. This gives good triangulation, and helps counter torque twist.



I'll second that movement, exactly as stated.

Once you have done both of these changes, disconnect the shocks at the top so you can play with the axle in your hands and look for any binding in the links. Fix that and you should be good to go.

Cheers.

you need to shorten the upper links so the links as a close as you can get on the axle, on the chassis the links need to be in the outer hole and on the out inside of the chassis, the lower links need to be on the out board side on the axle and on the chassis they need to be about a inch apart this will give you symmetrical triangulation. the triangles that the links make should be the same top and bottom.

[Duuuuuuuude]

Originally Posted by Terranaut

I agree that the upper links are too far apart at the axle. Move them as close together as you can without them touching each other. I have mine on just one bolt right in the middle, with one link above the plate and one below.

Originally Posted by brushlessemaxx

you need to shorten the upper links so the links as a close as you can get on the axle, on the chassis the links need to be in the outer hole and on the out inside of the chassis, the lower links need to be on the out board side on the axle and on the chassis they need to be about a inch apart this will give you symmetrical triangulation. the triangles that the links make should be the same top and bottom.

No, and no.

The upper links are fine. The lowers need to be moved closer together at the skid to provide triangulation.

Looking at the pics, the only other real issue I can see is that the upper links are possibly running out of room to move and contacting the plate. Try shimming them up a bit.

[billj]

Originally Posted by Duuuuuuuude

No, and no.

The upper links are fine. The lowers need to be moved closer together at the skid to provide triangulation.

Looking at the pics, the only other real issue I can see is that the upper links are possibly running out of room to move and contacting the plate. Try shimming them up a bit.

X2 what Duuuuuuuude says

[TSK]

It's definitely a combo of the equal length uppers and poor link geometry. You need to triangulate your links more.

With the equal length uppers, and the near parallel link geometry you have, It simply cannot let the suspension articulate properly. The easiest way I can explain is liek this. Grab a shoe box from end to end and try and twist it. The eight fixed point resist the twist or in this case the articulation.

[Duuuuuuuude]

Originally Posted by TheSCorpionKing

With the equal length uppers, and the near parallel link geometry you have, It simply cannot let the suspension articulate properly. The easiest way I can explain is liek this. Grab a shoe box from end to end and try and twist it. The eight fixed point resist the twist or in this case the articulation.

A shoe box isn't built with rod ends that have articulating balls. If it did, you'd be able to twist it around.

There are some of us that run equal length uppers that are nearly parallel with the chassis. It DOES NOT hinder articulation.

[TSK]

Originally Posted by Duuuuuuuude

A shoe box isn't built with rod ends that have articulating balls. If it did, you'd be able to twist it around.

There are some of us that run equal length uppers that are nearly parallel with the chassis. It DOES NOT hinder articulation.

I used to run a CDW with straight uppers. In trhis case it's not the fact that he is running equal length uppers that are near parallel with the chassis. My concern is that nothing is triangulated. His lowers are near parallel to each other, as well as his upper's. Sure there are vball ends, but that type of link lengths combined with there placement, limits the amount of aritculation possible (in my head anyways.) when viewed from the eend, having all his links in a box shaped, just doesn't geometrically allow flex. Having links triangulated, gives the links a trapezoidal shape when viewed from the end, and this allows the links to pivot around a fulcrum, allowiing more possible articulation. When you cycle a double triangulated suspension, the axle pivots around the lowers at the chassis end, and around the uppers at the axle end. Having equal length links, parallel each other (upper and lower) will result in a pivot point near dead center of upper and lower links at both the chassis and axle end, and geometrically, it limits the amount of possible articulation.

Did that rant make any sense

He should just unbolt his shocks, and see how much it can flex by hand.

[gottorque]

Heres how my truck is set up now. Notice how the uppers are just about parallel and slope upward from the chassis to my rear link plate. My lowers are as triangulated as they can be, without binding. I have near zero noticeable torque twist

[rockwha?]

check the thread "squat anti squat" tons of susp geometry to make your head hurt. And heavier oil or stiffer spings to fix torque twist is for people for dont understand how their crawler works.