I'm coming over in about 6 weeks time and wondered if it would be worth hiring a bike for a day or two to do some trails.

I will be hiring a car any way, but wondered if there are any decent trails to do around Calgary just to take in the sights?

Indeed young man, Calgary has many cycle trails and you will see a good(ish) number of people using bikes as a way around. Wether you will see all the 'sights' I'm not that sure, but you will be able to appreciate our 'urban countryside'. (if you giza bell I also have a great wee book called Calgarys Best Bike Rides and Trails' whioch you are free to peruse and\or borrow)

That's a good idea... I love the bike trails in Calgary but be prepared some of the distances are a bit mega unless you're a hardened veteran of the Lance Armstrong type. Our solution is to throw the bikes in the back of the truck and park at the trailhead (not so easy if you only have a wee hire car).

Somewhere to consider renting would be the University of Calgary.

City of Calgary bicycle pathway maps. Adobe Reader required.

By "sights" I mean within about 25 miles max each way. Unless it's git hilly and you can knock the 25miles down to 10 each way

Once you've looked at some of the maps available at the City website you could go here http://toporoute.com/ and try plotting your route it will give you the elevation changes.