You can upgrade the suspension. But it will probably cost about as much as the bike is worth.
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I'd love to make an excuse to get a new MTB but I've decided for now to maintain the poopy one I've got. If I were going to the bike store for a trail bike I'd take a long look at the Specialized Fuse and/or its direct competitors... Plus size tires, medium travel (4-5 inches) fork, slack head tube, dropper seat post. Either that or a Rockhopper, a line drive down the mainstream of what mountain bikes are each year.