ultimate hardtail

duncdan

my kona explosive is getting a bit ropey and I was contemplating a carbon replacement in the form of a cannondale taurine. However my riding style has changed and I fancy a long travel fork and possibly a titanium frame. Can you try to explain the differences in these 3 frame materials with out the words "springy feel"?

supersonic

A lot depends on construction, as all three can be as flexy or stiff as the designer wants. They do have unique properties though, and of course density varies. I could write a few thousand words lol, so I'd have a read of this:

http://spokesmanbicycles.com/page.cfm?PageID=328

Gets to the point: don't forget the links on the left for specific info on each material.

duncdan

Thanks for the link but there was no talk of how the science relates to ride characteristics

I could guess that steel has half the "spring" of titanium because the elogation is half although I dont understand the claimed shock absorbtion of carbon given its stiffness. OK it is all in the layup.

Maybe I should revise my question to compare the canondale taurine with the titanuim on one that are both so highly rated in the back of WMB. How would these bikes compare to my steel Kona?

supersonic

The build has a lot to do with it. With careful butting, oversizing and manipulation of the tubes the designer can get different frame 'feels' with the same materials. The stock values we see for materials such as stiffness, elongation etc are usually done on solid bars. Aluminium frames tend to be stiff due to the fatigue properties - the designer will oversize the tubes to reduce flex, and that low desnity lends itself well to this. Double a tubes diameter and you increase its stiffness by a factor of 8. You do reach a limit on how thin you can make the frame tube wall though. Light steel frames tend to be quite flexy, while titanium, sitting in the middle of alu and steel in stiffness, strength and density often has the most varied feel frame to frame.

High frequency buzz is a little different, and carbon seems to have damping properties. A lot of this is of course subjective, and other parts such as the tyres, bars, seatpost, saddle, fork and wheels all have a contributing effect.

I have ridden beautifully compliant and soft steel frames, and boneshakingly harsh ones. The only way is to test.