zukracer, your needs sound a whole lot like mine. I went 17/42, found the sweet spot I had been looking for.... but watch first gear, it's fry or fly, depending on your tire and how warm it is. This is definately a "seat of the pants" mod, you will feel it right away. For the first time, I am picking up the front tire just a bit coming out of the turns, feels great! I am a 2 thru 4 gear rider for the most part, all twisties and have found the 42t rear to be the ticket on the stock wheelbase. Just my cents worth....and, something to remember, by going with the stock chain, 112 links, and the 42, you are shortening the wheelbase by about a 1/4". Bike falls side to side a bit quicker....
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