Originally Posted by cyccommute

Let's start with a grammar lesson, shall we? "your" is a personal possessive pronoun relating to the speaker as in your bicycle or your tires. The contraction you are looking for is "you're" which is a shortening of the phrase "you are" as in "you are wrong" or "you're totally off base" or "you're full of crap". Of course that contraction is usually followed by a cogent argument as to why the subject of "you are" is wrong.

Aluminum gains it's <sic> stiffness from the tube diameters which resist bending, i.e. are stiffer, better than smaller tubes with thicker walls.

Originally Posted by HillRider

However, aluminum, due to it's <sic> fatique properties, is always made stiffer to reduce flex and improve longevity.