Hot tip on Matris.
My aim has always been "firm but compliant", for our rough roads - not smooth race tracks.
Research "stroke length" of shock as my Matris (MM101.02 R) was designed for a GRiSO, yet it has less stroke length than the stock sex Sachs.
Also Matris use an internal 'top out' spring while some other brands use an internal hard rubber stop. The spring, I believe, encroaches on your total travel, meaning its wasted within your static sag (they count it as travel, but you don't get to use it for effective bump control).
I removed the spring and added an internal spacer and 6mm rubber damper.
The secret:
When you jack the bike up taking all the weight off the back wheel, shock fully extended.
Take note of the bottom shock bolt position in relation to the horizontal link arms. Standard rising rate rocker ratio starts at 2.6:1 (2.6mm axle travel per 1mm shock travel) diminishing to 2.1:1 bottomed out.
The bolt head with Bella's stock shock (310mm eye-to-eye) is behind the horizontal link arm. If I tried to soften the ride by winding off pre-load, I just ended up with lots of sag, minimal travel and harsh ride, rocker was always operating in the highest part of its ratio (2.3:1 to 2.1:1)
The bolt head is now fully visible (below the horizontal arm) from the side of my bike when its on the side stand, my modified Matris free length is now 330mm eye to eye. By keeping the spring pre-load high and the rider sag nearer to its optimum, means on initial compression the rocker is operating in the 2.6:1 ratio area, giving better compliance as well as having longer travel than otherwise afforded by the stock Matris.