I just went through this with my axis 700 and ended up purchasing a Hunterworks cvt upgrade. I also use mine in the mountains of NC and even the 700 isn't geared for the mountains. No chip is going to makeup for this as they are just under powered for this purpose. The CVT clutch upgrade changes the gearing I would say significantly lowering the gearing for climbing hills. It will also drop your top end as well. If you go with a Hunterworks upgrade clutch you'll need a new belt as well.
If you are running this in the mountains you need to keep your UTV in lower gear. If you run it in high hear you'll destroy your clutch quickly.