This isn't something I can really give you a guide on other than looking out for certain name brands, other than that it's up to your own personal research and looking up used values. I did make a facebook guide from some friends a while back where I was trying to give a quick n' dirty rudimentary info dump because I was "the bike guy". This is mostly just info on OEM produced frames and bikes, I don't know as much about 3rd party:


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There's the big American 3: Trek, Giant, and Specialized as far as road frames go. Usually these companies produce pretty good bikes and utilize Shimano (Japanese) componentry, which is a good manufacturer as well. For the money and relibility I'd stick with these brands. Cannondale, Scott, and Felt are also a good brand but they tend to be slightly more expensive. Then there's the much more expensive options like the big Italian 3: Cervelo, Colnago, and Bianchi. Peugeot made some good bikes, but their components were sometimes proprietary and came in difficult to work with non-standard sizes.

As far as components go, the aforementioned Shimano makes great brakes, gear shifter assemblies, and gears (hereafter known as a groupset). The quality tier levels are Shimano Sora/Claris/Tiagra (Low tier) 105 (low-mid tier but still good), Ultegra (mid level) and Dura-Ace(top level race). There's also SRAM and Campagnolo (low-Centaur/Veloce, mid-Athena/Chorus, High-record, race- super record) which can be more expensive groupset manufacturers but fantastic quality.

Avoid Wal-Mart brands like the plague. Avoid unbranded groupsets like the plague. Let's just say you get what you pay for. Reliability and precision in the mechanisms is what's lacking with these cheaper no-name or generic brand parts and frames. If a manufacturer isn't willing to brand their product with their name then that component isn't something they are proud to have made or will stand by for warranty replacement.

A lighter bike means it will handle more nimbly, accelerate and decelerate more quickly, and make it easier to climb up hills. But it also means a lighter bike is more expensive and usually will only be felt if the bike is really light.

The difference is in the frame material, a steel bike is the heaviest, but is very tough. But not all steel is the same, if you decide to get a steel bike, there are several different grades which have different properties. Better steel bikes use strong steel so less of it is needed to contruct a bike, which makes it lighter overall. As a general rule avoid high tensile steel (hi-ten steel), it's a low grade, cheap, and unecessarily hefty. They are usually present on cheap-o bikes that aren't meant to last past the attention span of a child, like Wal-Mart bikes and fashion-fad fixed gear bikes. Aside from that there's LOTS of different steel grades, if you come across something you've never heard of just look it up. Columbus tubing, 507 tubing, chromoly-molybdenum etc. all have their pros and values depending on what bike it's on and who made it.

Aluminum is lighter, corrosion resistant, and can be cheaper, however they are not as durable. Just don't crash. 'Kay? Just like Steel, theres plenty of aluminum grades as well.

Carbon fiber is light, tough, and expensive. These days carbon bikes are becoming more and more common so the price is not as prohibitive as it was before. However this material does require special care, so do some research before buying a carbon bike (I own 3, it's by far my favorite material). There's plenty of grades and "eras" of carbon as well. Personally I think this matters less than Steel of Aluminum unless you're a professional racer.

Most bikes range between 21 to 30 pounds. Most sanctioned races require bikes to be no less than 15 pounds (Like pros in the Tour de France). The difference between a 15 pound bike and a 25 pound bike is 10 pounds and several thousand dollars. For many people it's a better option to just go on a diet.