If you compare a SM to a Sporty as far as what you get for your money I don't think there is any contest. I wanted the SM black engine and better breaks but I have the BA handle bars and pull back risers as well as the BA seat. My opinion on the SM vs. the BA is you look at the 2 and decide what you would want to change, then go with the one that would cost less or be easier to change. Like it is easier and less expensive to change the bars than to upgrade breaks. Under normal riding conditions I don't see much advantage to the dual disc since the BA single will lock up the front wheel if you yank it. Only advantage would be under very heavy use as in racing since the dual wouldn't get hot enough to fade as fast.

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