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Steel Scandium Titanium Carbon Fiber or Aluminum

No bike material is inherently better than another. Aluminum, Carbon Fiber, Scandium, Steel and Titanium and the like are all compromises between
flex, stiffness, weight and cost. This epinion will go into depth for each of them.

Aluminum
Standard: 6061-T6, 6061, 7005 T-6, 7005
Variations: CU92, Metal Matrix
Lightest Road Frame: 2.7lbs Klein Quantum Series
Lightest MTB Frame: 2.9lbs Klein Adroit Series
Aluminum is known for fat tubes and stiff rides. Any non steel bike under $1800 is probably going to be Aluminum.
On Straight Singletrack
Aluminum excels on straight courses, and also with climbs. Because of aluminum inherent stiffness, sprinting, climbing and the like are all very very
efficient.
On Twisty Singletrack
Similar as with straight singletrack, but as green points out in the Truth About Stiffness, it is slightly heavier to turn. But, many companies have
given aluminum frames slacker head angles, making them steer just a tad faster to compensate.
On Road
Except for aluminum only manufacturers (and Trek), there aren't that many aluminum road frames. Why? Aluminum also has a nasty tendency to transmit
vibrations in a big way. Road shock easily gets to the rider, therefore fatiguing the rider earlier.

Carbon Fiber
Standard: None
Variations: All proprietary
Lightest Road Frame: 2.2lbs Giant OCR Team
Lightest MTB Frame: 3.0lbs Trek Pro 9.9 and9.8 Elite
Hardly any company has used the same route with carbon fiber, and each of the bikes produced have slightly different feel. But, one characteristic is
very common: a mildly dull feeling compared to steel or aluminum or titanium. Also, Carbon fiber is not known for being cheap, either. However,
Carbon is resillient, and frames made from carbon are more forgiving, not to mention in general, lighter than their steel, aluminum and titanium
counterparts.
On Straight Singletrack
Carbon is usually forgiving vertically, but because it can be engineered, it can also be very stiff laterally, giving the bike good climbing
performance while sparing your backs from roots.
On Twisty Singletrack
This more or less depends on how stiff the company makes the carbon. But, as with aluminum, extreme stiffness may require slack head angles for quick
steering.
On Road
Carbon fiber was the weapon of choice for Tour de France winner Lance Armstrong in 1999. Carbon rocks on road, plain and simple. Lighter than steel,
easier on your body than aluminum, and more abundant than titanium frames (More selection).

Scandium
Standard: Easton Scandium
Variants: None
Lightest Road Frame: claimed <2.0lbs (!!!) from Santana (thank you, sweeper)
Lightest MTB Frame: <3.0lbs Voodoo Sobo
Super expensive dream metal that Easton has dreamed up, which had originally come from Russia (so the story goes, Scandium was the toughest metal
(alloy?) they could find to use in the nose cones of their ICBM's. Tough metal was needed to punch through the polar ice cap). However, because of
the relative lack of these frames, I will not comment on this metal manners. Light, less stiff than Aluminum, but still, not as sparing to your back
as the other materials except for aluminum

Steel
Standard: Reynolds steel, Reynolds 853 air hardened, True Temper
Variants: Many, proprietary
Lightest Weights: I do not know
The oldest and most well known bike frame material. Decently stiff, and yet, decently flexy, giving this material pretty desirable qualities.
However, to get stiffness or resilliency without the other requires a lot of manipulation, as on the Bianchi Grizzly. In general, heaviest of all
bike materials, if only by a margin. This metal is a lack of all trades metal, but none of it properties are inherently bad (except for rusting), and
none of them are particulary helpful.
On Straight Singletrack
Not as sprightly as aluminum or as twangy as titanium, but this material gets the job done, and it spares you from the extreme flexiness of titanium
or the extreme stiffness of aluminum.
On Twisty Singletrack
This is where steel shines. On the twisty sections of my rides, my 29lbs Trek 820 really doesn't feel too different from my 25lbs Klein Attitude or
24lbs Giant XTC. Steel flexes through the turns, in effect whipping you around somewhat. If this is where you ride, than this metal should be on your
short list.
On Road
Not light, but it combines the good qualities of carbon fiber (stiffness, somewhat) with the best qualities of titanium (flexiness, somewhat). Five
time Tour de France winner Miguel Indurain rode steel, and if you can afford high end road frames made out of carbon or titanium, or if you just like
steel? ride better, then consider steel. Schwinn top of the line road bike, the Paramount, is made from steel. That says something.

Titanium
Standard: 3v, 2.5Al or 6v, 4Al
Variants: None
Lightest Weights: I do not know
Considererd the best bike frame material by some, this material is light, strong, and undeniably flexy. To overcome this, Litespeed (the premier
titanium bike co.) has done some odd shapes in its tubes to fix this, but those bikes are also only affordable by rich, rich people.
On Straight Singletrack
Acceleration is on par with steel, and not as good as aluminum or carbon. But riding off rocks and roots is finally an enjoyable experience, as
frames are nice and supple. Climbing is effiecent, but again, not as brutally so as aluminum.
On Twisty Singletrack
Remember the whipping motion of steel as it pushes you through the turns? Well, it even more present in titanium. Very, very sweet riding. And have I
mentioned how forgiving it is over bumps?
On Road
Only if you have got the money, bub. Flexy, no road induced fatigue, or very little of it.

Last Word
Steel and Aluminum are the mainstream bike materials, with carbon fiber, titanium, and other materials making up the high end spectrum. Neither metal
is inherently better than the other.
Steel frames are good for comfort. Even though some very well designed aluminum bikes can have similar resillience, you just can't miss with steel
(we're only talking about comfort here). Steel is known as a bike material that can absork shock, especially crome-moly, and tuned crome-moly (butts,
tweaks, and other stuff that makes the frame react better than straight gauge steel). On rough roads and trails, this absorbtion translates as less
fatigue. However, this resillience is also side to side softness, which can make steering less true, pedaling slightly less efficient, and corners
less crisp. Steel, even Reynolds and Tange, can be slightly heavier than aluminum.
Enter aluminum. The current trend is towards fat tubed aluminum, which allows for a very stiff, very responsive bike. This stiffness and responsive
translates into pure speed and efficiency on roads and smooth singletrack, but it also translates into back breaking bumps and potholes. Turning is
sharper with an aluminum frame, but as soon as you hit a rock, the rear wheel will skip, which might hurt if you fall. There is very fine aluminum
tuning at the higher end of the spectrum from companies such as Cannondale and Klein, but there is a premium on these bikes: Price.
Which should you choose? if you can find good steel bikes, go for it. If you can find awesome aluminum bikes, go for it. But weigh your priorities
first.
Yes, the end. With your riding habits and places in mind, (and your pocketbooks too), you can now safely choose your weapon of choice.