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I just found the Race Tech rear shock spring for the CRF250L. It has options for spring rates but I'm not sure what the rates line up with. I weigh 200 pounds and am at about amateur motocross ability. My 2018 bottoms out HARD whenever I take it off-road at speed and I don't care very much about on-road performance. Is there a guide somewhere to tell me what the different rates mean?

Thanks in advance.

Quick update, I found the calculator on Race Tech's site and it looks like the 12.5Kg is the one I need.