Chromoly VS. Aluminum!?

Question

I am getting a hybrid bike that I will ride on both sidewalks and roads. I want a bike thats lite, but will last a long time. Right know I'm comparing the Specialized Globe City, and the Motobecane Cafe Noir. What do you think?

Answer 1

I'd usually go for AL every time. Lighter and stiffer it's plenty strong enough for almost everyone. But the Moto is a better bike with much better components. However, I would check out Cannondale and Trek for better AL bikes: they both have some sweet hybrids this year.

Answer 2

chromoly all the way its stronger and lighter

Answer 3

Wow the long point that MirageGuru made was more applicable to road racing bikes. The much more important issue to you would be fit. Which ever bike fits you better would be the one to get (a good shop should be able to help you on this).

Another question is value. You can find the Motobecane on-line for a great deal:

http://www.bikesdirect.com/products/moto...

Answer 4

I guess you are asking 2 different questions. I'll tackle the Chrome Moly vs. aluminum question.

There are 2 very common steels in bicycle manufacture. One is called Hi Tensile and one is Chrome Moly (or cromoly or cromo or CrMo). Cr Mo and Hiten steels weigh virtually the same but CrMo is stronger which means that you can use less material and maintain strength. Less material=less weight. OK?

This does NOT necessarily mean it is heavier than aluminum especially with the bikes to which you are referring. In the grand scheme of things the frames of these bikes weigh almost the same.

It's a fact that aluminum is generally 1/2 the weight of steel but it is also 1/3 the strength. This means that you need 3 times the volume of aluminum to meet the strength of steel. This is why cheap aluminum frames tend to weigh more than their steel counterparts. Aluminum also has a limited life- it will eventually fail- while steel has a relatively unlimited life.

Yes, steel rusts, but aluminum corrodes and it can be argued that corroded aluminum is much more risky than rusted steel. Neither of these should be an issue if the bike is maintained.

Aluminum has the reputation of being a stiffer ride which transmits more of your energy to the ground but also transmits road roughness to you. Steel is much more compliant but not quite as energy efficient.

Soooo, if you want the smoothest possible ride, get steel. If you want more efficient use of your energy at the expense of comfort, get aluminum.

Answer 5

I find that most aluminium bikes are plenty strong enough (even for *my* riding habits, which tend to be rough), and I think chromoly is a bit problematic because it's not rust proof.

If you want something extremely light and strong and rust resistent (and have enough money) I recommend getting a titanium frame. Titanium is the strongest metal on the periodic table, and I think also including alloys, but not sure. It's also rust resistent, and that makes it good for all weather.