I have 11:1 pistons and FCRs (that I bought from Chris) on my 1997 900 SS. While the pistons helped the power (no problem using 85-87 octane gas either, depending on elevation), they were nothing like the improvement I got from the carbs. And the lack of choke is a non-issue. I live in Wyoming at 6000' and I don't miss it at all. Of all the places I've bought crap for my bike, Chris has been the best
Joe