Discreet but capable

Sorry but you're misunderstanding your own explanation. The length of the drop links is not how you adjust the resistance of the anti roll bars. On a Jimny the anti roll bar is a fixed rate item. It only has one hole in each end of the lever arm therefore the effect of the lever is static and unadjustable. If you raise the relative position of the chassis to the axle the anti roll bar is then no longer sat with the arms level to the chassis and the drop links are no longer vertical. This creates 2 main problems. First the way any forces are transferred through the links and chassis bushes is in a plane they aren't designed to accommodate causing severe wear. Secondly as the suspension flexes there is a greatly increased risk of the link and lever arm becoming straight to each other and even going beyond that and inverting which is very very bad. What your adjustable drop links do is give you the means to re level the lever arms so that the system is operating as it should. They also have the added benefit of being much more robust than the factory ones meaning that they transmit the forces more efficiently into the arb. In order for the effective rate of the bar to be tuned you would need lever arms with multiple holes at various distances from the mounted axis of rotation of the bar at the chassis end. These will then alter the leverage ratio where a set of holes near the rotation axis make the bar seem firmer and a set of holes away from the rotation axis make it feel softer.

Lambert, I think it's you who has the wrong end of the stick.........

Raising my car has increased the preload on the ARB, the distance between the axle and the lower point of the ARB is now greater than it was. The link length is the same so the tension it is under is greater.

This has affected the suspension negatively (adding a spring where there shouldn't be one), to a certain degree you can negate this increased ARB "bounce" by increasing the damping rate.

Increasing the damping rate will only go so far (and not that far) to negate the preload or spring. The damper pushing against the spring....

If you look back in my build post, when I changed to Superpro ARB bushes, there was a change in the ARB behaviour, I was able to address it by increasing the damping.

I said that I could tune out some of the effects of the increased preload by increasing the damper rate, I didn't say that you tune your ARB by fitting adjustable links, which I stand by. I shall be trying later today.....If I cannot achieve the desired effect, then adjustable links will be required.

Don't know where adjusting the resistance of the ARB has come in to it... that was never a stated aim.

"Only had a short drive on a tight and twisty back road and it feels different, a tad twitchy on the steering but I think that's because the lift has tightened the anti roll bar. I might be able to adjust the dampers to address it or it's another spend on adjustable drop links."

I think you've grabbed my phrase "tune it out" and taken that to mean much more, a few clicks of adjustment on the dampers, if that sorts it, great.
If not, then it's £80 worth of shiny bits..... Superpro adjustable drop links. They will adjust to remove the preload or "tune it out".......

I use the word "tune" to confer the small adjustment of one component which may affect the behaviour of another component.

I can't see where or why you would disagree with that, I'm proper confused pal....

sniper

:laugh: :laugh: :laugh: :laugh: :laugh: :laugh: :laugh: :dry: :laugh: :laugh: :laugh: :laugh: :laugh: :laugh: :laugh: :laugh:

The anti roll bar is a spring acting against itself. It is attached to the car via 2 bushes that allow it to rotate relatively freely on an axis of rotation of parallel to the axle. It is not solidly affixed to the car. It acts by compensating between the loads applied to it at each end by the axles flex via linkages attached to the return arms which are essentially fixed length levers. At rest on level ground there is no tension in the anti roll bar. It has no static load bearing capacity. The relative length of the linkages has no bearing whatsoever on the effective length of the lever arms. The only way to preload the bar is if you're going to artificially lengthen one linkage more than the other but doing so is monumentally dangerous as the car will no longer have an equal roll response in both directions.

You are missing the point..... I understand that there is no preload designed into the ARB. Once a load (roll) is applied, forces along the ARB are torsional, the load fixes one end and the ARB applies force to the other.

My problem is that the axle is now further away from the ARB, this has changed the angle and tension on the standard length drop links. They should be vertical and under no tension. These angles have been changed by moving the bottom datum (axle) lower, this has pulled the ARB down and made the drop links sit at an angle. These small changes have caused a spring action across the ARB, that is what I am addressing.

If the drop links are extended so that the roll bar and the drop links are back in their neutral position, the spring that I'm experiencing will no longer be there. It couldn't be simpler...... restoring the ARB to normal position.

If the dampers can't absorb that spring, lengthen the drop links to remove it. Both links will be fitted at the same length.

I can't explain anymore than I have done, sorry.

Adjustable drop links are used on most tuned suspension systems, they can also be adjusted to help with small corner weight changes, they are a very common piece of kit. Why do you think they have no impact ?

Have a look at chassis dynamics by Sam Borgman at Torque Developments.

sniper

When the preload gets to much.