What's with aluminum frames

[SoFlo]

I was reading a review on a dirtbike the other day that said, "when you can ride on an aluminum frame, and not notice it, then that's a good frame", or something to that effect. I guess they give a harsher ride? Why, because they're more rigid?
And if those are the cons, what are the pros or these frames?
Is it anything a novice would notice or care about?
:ride:

 

[AnTs]

Its light weight... i went from a yz250F to a cr 250... and when i jumped the cr250 i like flewww way paste the landing ramp and landed in bushes... you deffinatley can tell when your jumping. Also when we lift it into the truck its easy and when we put it up in the sunroom its very easy...

 

[shadow171]

Why do you sun your bike? :rotfl: I also here that getting it some good beauty rest makes them run better, just joking.

 

[SoFlo]

Its light weight... i went from a yz250F to a cr 250... and when i jumped the cr250 i like flewww way paste the landing ramp and landed in bushes... you deffinatley can tell when your jumping. Also when we lift it into the truck its easy and when we put it up in the sunroom its very easy...

So the weight is for sure one thing.
Is it stronger than the steel type?

 

[oldfrt613]

Aluminum is not stronger than steel per say, but it does have a higher specific strength - that is for a given job, aluminum can be made lighter than steel - it will take more aluminum ( more volume ), but it will weigh less than its steel counterpart in the end.

 

[mx547]

the biggest benefit is that they look so damn cool. :aj:

 

[kx250kev]

I think some of it has to do with frame flex. I remember when the new 97 CR's came out, many complained of a harsh ride. I never rode one, but I've talked to those who had them. Many got rid of them soon after.

 

[oldfrt613]

Had an infamous '97 - wasn't the frame - atrocious valving on the forks - I lovingly called it the "swap monster" until revalve. The '97 frame was actually too stiff - suspension had to do all the work. Frame is a favorite among jumpers.

 

[+30]

alum

I like the alum frame everything is well positioned, everything fits without pushing and shoving and preloading like my 04 rm. As an intermediate vet mxer I cant feel a quantifiable difference in stiffness between the cr and rm, but I do like the balance of the cr better. Most contribe this to the frame. I think it just fits me better. It has been through alot of abuse with no problems. and no rust to worry about. I know I know alum corrodes. blah blah,,,,I would worry more about the motor of your next bike than the frame though. No one I know has broken any part of a cr falumi frame, but several friends have broken steel frames, pegs, linkage mounts etc....

 

[mxneagle]

I always get a chuckle out of the comments by the novice riders who review the aluminum frames and comment about it being too rigid and wishing it had the flex of a steel frame. Like they can actually ride the bike hard enough to notice the difference. If a magazine were to say the frames flexed too much they would come back and tell you they could feel the frame moving too much and and giving them a mushy feeling in the whoops. For 99% of us it is the suspension is the biggest issue.

 

[Masterphil]

I'll stick with the good stuff, 4130 STEEL BABY!!! Powdercoating sure does hold up a lot better than paint. Looks better than that dirty stained aluminum, too!