Not sure, even a light bike when wet is around 140 making close to 70kg initial weight on the spring assuming a slight front weight bias. 70kg is still quite a lot of weight!

When you add your own weight of say 80-90kg don't forget this is distributed and not ALL on the rear shock so you may only increase the weight on the rear shock by 50-60, LESS than exerted by the bike.

Maybe someone here can do the maths better than me?
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