If steel and titanium are both equal in strength, then aluminum is half the strength. When you get into the 7000 series of aluminum they get to about two thirds the strength of titanium. The problem is that the ductility of aluminum is less than steel. This is what comes into play when designing parts, especially the axles and some bolts, like cylinder head bolts, the stretchiness becomes an issue with titanium. And the technical term for that is modulus of elasticity. That's why a when looking at a titanium spring, it has less coils in it. With the modulus number of titanium being half of steel it's going to flex twice as much for the same amount of load.
So let's give an example. Let's say it's a steel bolt and you give it 1,000 pounds of force on the bolt, the bolt is going to stretch a certain amount. A titanium bolt with that same 1000 pounds of force is going to stretch twice as much. Because of stretching it will still carry the load as long as you are within the elastic limit. That's why people say they have a problem with the bolt stretching, but they both stretch until they come up to the clamp load that holds the assembly together. In motorcycle terms we see this in the triple clamps. There have only been a few riders we know that have the ability to tell the difference between steel bolts and titanium bolts. That same rider can tell the difference between 15 foot-pounds and 18 foot-pounds of torque. There are only a few riders that are that sensitive to tell the tiny differences in the triple clamps. Across the board right now we pretty much have everybody running titanium triple clamp bolts and titanium front axle pinch bolts.
