I see you posted that your a design engineer so I don't need to tell you anything about structual design failures but I'm not convinced that the rear lower subframe mount would be strong enough to take the loads your going to be asking of it. Of course I'm just eyeball engineering it so that's not very scientific in itself.
I'm just comparing it to the oem lugs cast into the frame and swingarm.
The loads are quite high compared to most other areas on the chassis.
What scares me is cast alluminium frame sections aren't very forgiving in failure like mild steel.
Mild steel will enongate, deform and at least give you some indication that complete failure is around the corner.
Cast alloys just fracture.
I'm sure the safety factors are quite high for production motorcycles and eating in to that I'm ok with if the use of the end product is more closely known.
Personally I would be bracing the subframe to spread the load across the subframe to allow the four mounts to share the load.
I say all this because it would be a sad thing to hear of a subsequent failure and injury to yourself, and also hoping to learn something from yourself whom is pushing the boundaries and has technical abilities I don't ie. Engineering design calculations.
I did some real quick arithmetic (not my strong point) and a 9.5kg/mm spring at full bump of 65mm (shock stroke) will take 617kg of mass to keep it bottomed out. So over 1/2 a ton of force which is quite significant. I hope you get what I'm talking about and don't take me as a condescending *****, a common criticism leveled at me!....
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