I got a Schwinn 21speed. I have had it for 4 years now and I ride that thing pretty damn hard including jumping it off some loading docks and crap like that and that thing hasn't failed YET. The back rim is only bent sooooo little that I don't even think it's the rim I think it was because when I put on a new tire that it is kinda out of alignment. But I suggest a Schwinn, but I'm sure there are plenty other bikes out there. Oh yeah and mine costed $285
Brooks speaks truth. Think about it this way, you are going to have it for a long time. If you get a good bike you will probably have it for over five years, more like 10+.
I went through this a few years back and went with a GT hybrid. It's a really nice bike that was in my price range $300 - 400. I was going to go with a Cannondale which was a little more than I wanted to spend. In hindsight, I should have just went for it instead of being a cheapo and saving the $75 or so bucks I ended up saving.
I just went through this exercise about two months ago. I've had some "Toy Store" bikes by Huffy and Murray in the past. Those are the bikes that were hanging on my rack in the garage and ont being utilized. I found a Schwinn 26" bike that is a 21 speed with aluminum rims. With the Schwinn, I was able to pick out a frame that was comfortable for me - 23" between where the crank starts to where the post for the bike seat gets inserted. For so many years, I was using frames that were undersized and uncomfortable.
The Schwinn has Shimano grip shifters that are quite comfortable and the brakes are nicely re-inforced to the frame and the forks. The bike that I found is the "Frontier" which is a hybrid bike. The price was under $250, but it's the perfect bike for myself.
As the others have recommended, purchase from a reputable bike shop. Even though you'll spend a few more $$, the difference in price will quickly disappear. Usually, bike shops throw in a free tune-up that can be used in the future, plus some other incentives. I don't think that I'd want the "stock boy" from Toys R Us making adjustments on my bike.
First of all...walking is a lot better for you than riding a bike, if you want to get in shape. If you are a guy, riding a bike will do nothing to help shore up the muscles that are straining trying to hold back your gut.
Secondly, walking is a lot cheaper.
If you insist on getting a bike, make sure you also do something about your back muscles and your stomach muscles.
As far as the bike goes...what are you going to be doing with it? Commuting? Trail riding? Road riding? Getting in shape? Sidewalk? Beach?
Buying a $300 bike isn't going to help you get in shape. What kind of bike you get depends upon how you plan to use it. If you just need something to get around town then my advice is to go to Wallmart and spend > $100 on one of their Roadmasters. If you find yourself really getting into biking, consider upgrading to a "real" bike with extras such as shocks, lighter alloy frames, and so forth within a year.
But a $79 Roadmaster will do you fine for just getting around town, and you can use the money you save to take advantage of the deals in the hot deals forum.
Riding a bike and help tone your body. If you just sit on the seat and peddle it is not going to do much, but if you are going up hills and down bumpy terrain it really helps overall. I am not saying it's the end-all but it really toned me up a lot.
Yeah, like Croton said, get a good seat. You can get a jelly seat cover for like $20 at the bike shop. Your arse will thank you for it.
Also spend the money on a good helmet.
My Fuji Roubaix is about 6 years old now. I paid 600 for it and it rides just as good today as the day I bought it...better in fact, because it is now perfectly fitted for me. If I were starting out, and was serious about biking, I would not consider paying less than 400 bucks for a bike. If you are just going to be a casual rider, spend around $300.
Another possibility is going to police bike auctions...every decent sized municipality has them.
If you want to just tool around town, go to a bike store and be ready to answer questions like: What kind of terrain is around your house? Do you intend to ride this off road or just street ride? How much riding do you plan on doing (miles per week, etc.)? How much biking experience do you have?
If the bike shop salesperson does NOT ask you questions like these, RUN out of the shop--they are more interested in making a buck than making sure you get the bike that is right for you. Also, BUY AND WEAR a helmet. Can't stress that enough.