difference between alum & steel frame ?

[lilserve67]

Yamaha web site say's the 07 WR with the aluminum frame and the 06 steel frame dry weight difference is 1LB ?

Are they bluffing?! Shouldn't the aluminum frame be more than a 1 lb difference????

[Matt96xr6]

nope. I see you are like about a month behind times and about 2 years behind the info curve. Yamaha has ALWAYS said that the aluminum frame was NOT for weight savings. But for handling.

[Way Fast Whitey]

yes, we all know aluminum is lighter than steel. but for the frame to have the same strength, there needs to be more material. ?

[lilserve67]

I see I have some catching up to do ?

[Dwight_Rudder]

I even doubt there is a 1lb. difference. Aluminum isn't even good for handling. Too stiff once you get the strength. The best a manufacturer can hope for is to make it handle as well as a steel frame. Aluminum in more readily available in Japan than steel.

Cher'o,

Dwight

[Matt96xr6]

I even doubt there is a 1lb. difference. Aluminum isn't even good for handling. Too stiff once you get the strength. The best a manufacturer can hope for is to make it handle as well as a steel frame. Aluminum in more readily available in Japan than steel.

Cher'o,

Dwight

That is why the frame is made out of 7 different pieces that are forged or cast, some are welded. Aluminum has more flexibility to cast and forge things.

[Turismo]

Yamaha has ALWAYS said that the aluminum frame was NOT for weight savings. But for handling.

They succeeded BIG TIME!!! ?

[Turismo]

Aluminum in more readily available in Japan than steel.

Are you a business analyst now too?

Considering Japan has no aluminum smelters, I think you are way off the mark.

[The Spanky]

Aluminum does save weight, but not in the way you might think. A steel frame that has the same strength, rigidity, and stiffness of the current Yamaha frame would weigh several pounds more. By changing to aluminum, they were able to substantially increase torsional and longitudinal rigidity and strength (to reduce twist and "stretch") without adding any weight compared to the previous steel frame.

An aluminum frame can be made much stronger and stiffer than a steel frame of identical weight, as witnessed by the too-stiff first and second generation CR frames. And the combination of extrusions, castings, and forgings in Yamaha's frame gives them previously impossible abilities for tuning the stiffness and strength of the frame in specific areas to allow them to achieve any "feel" that they want.

The bigest advantage to Yamaha's new frame is in durability. Due to the increased structural stability, "stretch" is no longer a problem. Their steel frames were notorious for stretching (the wheelbase would actually increase by as much as a half-inch) through the course of a season of hammering by pro-level riders. The aluminum frame doesn't do this.