IF that's what you want...strictly a little more torque. No real comparison between a big-bore 9 and a stock 12 though.(Especially if you do the 9 'right'....cams, heads, good crank and bump the rev-limiter up to 7800 or so). THEN you have a seriously fun ride! Erik Buells' favorite personal bike was a big-bore 9 bike. It's probably an SX now though! Lol! But even with just a big bore kit, those extra RPM (vs the 12) coming out of the twisties (and rolling INTO them!) feel SO good!best bang for your buck realistically would be to sell your xb9, and get a xb12.
No better question to be asked. Guys came into the engine shop and this was one of the FIRST questions we asked.How many bucks do you have? That will determine how to best spend them
It SHOULD be a very flat curve.....these things are far from a peaky engine.high arc dyno curve..
I never did the math on the small bore kit to verify this, but I'll take your word for it! This is a fine 'upgrade' if you're just freshening up an engine that has a bunch of miles on it, or somehow got the cylinders hurt. For a real upgrade, go with the big-bore kit. (3-13/16" bore). with a bore of 3.8125 inches and stroke of 3.125 inches gives you 1,169.42cc. Yes, you must bore the cases....so be it. At this point of a build it isn't a big deal. (I sure would imagine you'd want the WHOLE bottom end done right anyways if you're that serious about it. I know I do.).In reality the 1050 kit is only 1021cc