Vancouver is the most bicycle friendly city in Canada (arguably North America) and one of the easiest ways to see the city in the dry months is by bicycle.
To borrow a bike short term, hotels like the Opus have bicycles in house that you can use for a day. Also, the city is working on developing a Barclay style public bike system like found in Europe and Eastern Canada. Bike rental shops are all over the city (e.g. Spokes and BC Rentals) and are easily accessible from the sea wall.
In our case, we knew that I’d be in Vancouver for a year. So, instead of spending a ton of money on renting a bike, I went to Our Community Bike and purchased a bike. At the end of my stay in Vancouver I brought it back and re-donated it. The Community Bike concept is absolutely wonderful: people donate their bikes to the shop where they are fixed up and used as part of the Free Bike Program (gives bikes to people who can’t afford them) or are resold. Money from the sales help support initiatives like Women on Wheels.
In terms of getting around, we tended to avoid the sea wall bike path because we found that other cyclists on the path were not very polite or forgiving. In one case, Niña was riding her bike for the very first time and she wiped out. As she was struggling to get out from under the bike a man came by and screamed at her to get the **ck out of the way. To their credit, all the other people that witnessed the event screamed back at him.
We found that the separated bicycle lanes around the city were perfectly fine (e.g on Hornby and the Burrard Bridge). They weren’t too hard or too busy and once Niña understood the lights and “rules of bicycling” she became an old pro.
Some things you should know about biking in Vancouver: bike theft is extremely common. One of my coworkers had his bike and lock stolen from a very public area (within days of purchasing it). My own bike was stripped down inside the “secured” parking garage of our hotel. Also, Vancouver has very specific laws regarding what you need to have in order to ride a bike (e.g. a helmet). These should be read before biking in the city.