are bikes made of alloy lighter or metal lighter?

Question

im getting a new bike but i dont know which is better

Answer 1

THIS IS A LONG ANSWER, BUT IMPORTANT!

Alloy and metal are the same thing.

Steel, for example, is made mostly of iron, but can also include carbon, manganese, molybdneum, nickel, and chromium. Sooo, all steel is alloy, and all steel weighs the same. The difference is by changing the metals in the mix the alloy becomes stronger, so less material is necessary to make the frame...less material=less weight. Steel, with regards to a bike frame, is typically indestructible...it is usually joints that fail, or some contamination that causes the metal to fail, or structural damage done to it.

Aluminum is a base metal and is always mixed with other metals, then usually aged or heat treated to provide desired effects. So, in the case of completed bicycle frames, this is also an alloy. VERY IMPORTANT- all aluminum alloys will eventually fatigue and break because as you ride a bike the frame flexes. Usually the failure is pretty spectacular and can cause injury to the person riding the bike. Aluminum is 1/2 the weight of steel but also 1/3 the strength, so in theory you need 3 times the amount of aluminum to equal the strength of steel.

Carbon fiber frames are an alloy of sorts, but is called a "composite". Ultimately what happens is that cloth woven of carbon (or pieces of carbon) is saturated with varying amounts of epoxy resin and then formed into a tube, or perhaps placed in a mold to make a "monocoque" frame. Sometimes carbon fibers are combined with fiberglas or other materials, these are sometimes called "ceramics". An example of ceramic is M2 material by Specialized. Carbon fiber and ceramic will also eventually fail, just as aluminum will.

The idea here is not to worry so much about weight, but to choose the material best suited to your use. If performance is a concern, FIRST reduce rotating mass (wheels, etc) before frames or handlebars or other non-moving parts. Saving an ounce off a tire/tube combination will be similar in performance as a pound off the frame!

Answer 2

Alloys are just a mix of different metals, so all metal bikes are made from alloys. If you don't understand that, you're not really after a light bike, are you?

What is usually referred to as "alloy" is aluminum, but it depends on who's making the bike that makes the frame lighter. NOTHING you buy at Wal-Mart, Target, Costco, etc will be worth a crap, so don't bother looking there if you really want a light bike.

Aluminum is 1/3 the weight of steel, but only half the strength and has a shorter fatigue life. So to make a bike frame out of aluminum requires twice the amount of material as a steel frame.

Titanium weighs half as much as steel, but is just as strong and won't rust. It is difficult to work with, and much of the cost of titanium is in the work required to make it into something.

Answer 3

The lightest are carbon fiber, then aluminum and then steel frames . Generally, the lighter, the more expensive. I would go with aluminum. Trek and Specialized make nice bikes in different price ranges.

Answer 4

All bikes are made of metal alloys...
Except those made of carbon fiber...