The 800 should be in the ballpark, according to the range. But if it feels way oversprung, I'd order a 700# from an outfit that also carries a 600 or 650. That way you can put it on, test it out, then exchange it if you still need to adjust down. You'll be out a little shipping maybe but better than being stuck with another wrong-weight spring.
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Originally Posted by Mark Twain
"Don't argue with stupid people; they will drag you down to their level and then beat you with experience."