From here the way is dry and clear and hugely fun on the bike, back the way I came through the Lewis Pass, Lake Tekapo and Burkes Pass. I'd recommend the lunch stop at Fairly rather than Tekapo, in fact anywhere the Kiwi Experience bus doesn't stop is probably good.
The sights of the McKenzie are spectacular, Mount Cook, mustering, all sorts! It really is a must see.
The cloud comes back at the end of the McKenzie, low and cool again, even a bit of drizzle. The Great Divide really is just that, the weather is radically different on the two sides.
Got down to just a litre of gas left, you really do have to think about fuel planning and refuelling in good time or you end up at some pretty out of the way places. Driving/stopping time was about 6 hours, partly due to some scenic detours and partly because it's a seriously long way and I've been hugging the speed limit (mostly).