I'm going to be in Christchurch in a week or so. Unfortunately my plans of 3-4 days free haven't come through and I'm only going to be able to do day rides around Christchurch or nearby parts of Canterbury, round trip 4 hours maximum. This will be on a hire bike, as Jetstar charges by weight; other Aust/NZ airlines count a bike as a single piece of sporting equipment, nominal weight 5kg.
Any suggestions? Anything to see in the hills inland? How about the coast? Akaroa is too far.
If you've got a mountain bike, you can have a lot of fun out at Bottle Lake forest. The council has built a whole rabbit warren of cycling trails through the pine forest along the beach. It's not crazy downhill stuff.
They've also just built a MTB track at MacLean's Island, but it's only a single path so it's less interesting and probably only takes about 40 minutes.
They're building a rail trail ride from the city out towards Little River. I've heard that it's a nice ride and you could do part of that. I think it has a couple of websites (for example www.littleriverrailtrail.co.nz/). If you skip a couple of sections you can get on it at Tai Tapu and ride from there.
You can always just go for a ride on the Canterbury plains, they're flat but probably not very interesting.
Keep an eye on the weather. It's absolutely miserable today. It looks like winter is properly here.
Interestingly, I'm just off to Melbourne in 4 days. I'll give you a wave if our planes cross in mid-air.
Head to the Port Hills. Any bike shop will point you in the direction (they can be seen from anywhere in Christchurch). You want to play around in Vic Park (Victoria Park) if you are into your mountain biking. A great scenic route is up Rapaki and along the top of the port hills (sidling around the Summit Road) and dropping into Taylors mistake then biking through Sumner and back to the city centre, about 50 km round trip from memory.