We keep saying it again and again, but swamping out a set of a sprockets is a cheap and easy way to make your bike "feel" faster.
I just installed a set of Supersprox Sprockets, 1 down, 0 up.
When someone says 1 down, 2 up or 1 down, 5 up, they are referring to the number of teeth in the sprocket. Typically you drop a tooth in the front and add teeth in the rear to make a bike feel more street able.
Going down 1 tooth is the same as going up 3 in the rear, so be careful and try and find the right gearing for your riding style.
Good luck!
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