3 - (probably not b4 25th) aftermarket shock. My question is: does an aftermarket gen 4 shock need aftermarket linkage?
You asked similar question in other thread, here is what I know:
a) Gen4 link ratio is arround 2.3, gen5 is where most sport bikes are 2.1. Ohlins for gen4 ships with 110 spring and Ohlins for gen5 with 95 spring. Gen5 has more shaft movement and valving is different too. Gen4 link could theoretically be as good with 10-12% more spring and more shim stack, but in practice people report gen5 setup (MSS, Attach) working better, can confirm this myself.
b) If you get aftermarket shock what is not revalved and has spring arround 110 N/mm, then it is designed for gen4 link and should work ok with gen4 link. Going with gen5 link and aftermarket unchanged shock (for gen4), it should work ok too when using correct spring (minus 10 compared to gen4).
c) My experience with gen4 and Ohlins was: myself 85kg naked, fast pace with slicks, used gen4 Ohlins as it ships from Ohlins, tried 110, 115 and 120 spring and had very often some tearing happening (thinking maybe its normal). Did not try to fix this with different valving. Then upgraded to gen5 link together with valving recommendation from LDH and lighter spring (100, 105). Boom, now tire wear changed to prefect and tearing rarely happens (bad weather). Great return of investment if you need 20 rear tires instead 26 per season.