The 'ZA' model has less suspension travel (160mm) and sits lower, and for this reason the forks are different and there is also no room for preload adjusters on top. As far as I am aware, the only reason that the bike's with ABS are lower (both front and rear) is because Yamaha's market research dictated that the sort of buyer who wants ABS also prefers to have a lower seat and both feet firmly planted on the ground. It is nothing to do with cost.

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