For calculating loads at the LCA-upright node we can use the front wheel forces at the contact patch and make some assumptions. We assume that:

Forces balance out
The LCA-upright node resists forces in all directions
The only forces on the upright are from the contact patch, UCA, and LCA
The LCA provides no restorative moment about the X or Z (depends on mounting)
The moment of the upright about the Y-axis is handled by the steering system
The LCA clevis does not provide a moment about the X-axis
The pushrod is mounted at a 60-degree angle (currently 63)
The coilover has no effect on the y reaction of the pushrod (any sufficiently long corner will fully compress the coilover)
The LCA-upright node does not travel more than 30mm in the Y from its clevis (currently about 25mm with a coilover compression of 40mm)

This means that for analysis purposes, we can treat it as exactly horizontal. This causes no more than 0.5% of error in this analysis.

We have the X-axis and Z-axis loads at the UCA-upright node and at the contact patch. Since the sum of these forces must equal zero, we can sum and negate the UCA and contact patch forces to find the forces in the LCA. We know that the forces in the Y-axis must cancel out, so all Y-axis forces at the contact patch must be opposed by the LCA.

Worst Case Loading (N)
Conditions	Fx at LCA node	Fy at LCA node	Fz at LCA node
Braking & Cornering Inner (inside front wheel)	-2367	-3012	-2230
Braking & Cornering Outer (outside front wheel)	4733	-5272	-2230

To resolve this force we first need the compressive force in the pushrod. Since the moment in the X-axis about the LCA clevis must be zero, the pushrod must provide a force in the Y direction that counteracts the force at the LCA node. We can then find the reaction that the LCA provides. The ratio of the pushrod force to the contact patch force is determined by the length ratios of the clevis to the pushrod node and to the upright node. The ratio is currently 340mm/213mm, which works out to 1.6. For safety, we will consider this ratio to be 1.8.

The pushrod will be mounted at a 60-degree angle, so we can get the force it exerts in the Z-axis as well.

Worst Case Loading (N)
Conditions	Fy at pushrod node	Fz at pushrod node	Fpushrod [compressive]
Braking & Cornering Inner (inside front wheel)	5422	3130	6261
Braking & Cornering Outer (outside front wheel)	9490	5479	10958

Since these forces must cancel out in all directions, we can sum the reactions we have calculated to find the force the LCA exerts on its clevis.

Worst Case Loading (N)
Conditions	Fx at clevis	Fy at clevis	Fz at clevis
Braking & Cornering Inner (inside front wheel)	2367	-2410	-900
Braking & Cornering Outer (outside front wheel)	-4733	-4218	-3249

Since the contact patch forces are not directly in line with the clevis, the LCA creates a moment about the clevis node. The clevis provides no moment in the X, so we simply calculate the moments in the Y and Z. The distances involved are listed below, rounded up by 10-15%.

Using these distances and the forces we calculated earlier, we arrive at the moments below.

Worst Case Loading (Nm)
Conditions	My at clevis	Mz at clevis
Braking & Cornering Inner (inside front wheel)	-431	-343
Braking & Cornering Outer (outside front wheel)	1212	601

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