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Presenting the details on the new DEAN...(7 posts)

Presenting the details on the new DEAN...sn69
Oct 21, 2002 4:27 PM
http://www.deanusa.com/carbon%20cti/carbonecti.htm

The El Carbone, which some of us have wondered about following Interbike. While most of us assumed it was another variation of the Odo/Ott/Cielo, it seems to be a bit different. Apparently the top and seat tubes are externally butted ti wrapped in carbon. The seat stays are standard Columbus Carve stays.

OK material engineers...can you please explain plusses and minuses of this design over a fully carbon tubed bike like the other three? Does the carbon over ti do anything?

The bike is $2500, which isn't bad for a custom, high end bike. Still, if this offers nothing in reality, a better bet would be the ED XL CTi.

Now, if only Tom will post pix of the new Spectrum ti/carbon uber-rig (that will no doubt require selling a kidney to afford).

Scott
oops...meant to say frame, not bike, for $2500sn69
Oct 21, 2002 4:27 PM
I don't get itfiltersweep
Oct 21, 2002 5:59 PM
What is the point of "WRAPPING" a Ti tube in carbon? Forget about explaining "plusses and minuses of this design over a fully carbon tubed bike"- explain the advantages of it over a full Ti bike? I saw another bike like this, and it seems like a marketing gimmick.
That's what I thoughtsn69
Oct 22, 2002 5:07 AM
I can't see any inherent benefit in wrapping the tubes unless the external butts are unsightly. Even then, Seven externally butts, right? Their tubes don't look bizarre.

I agree...I don't get it.
re: Presenting the details on the new DEAN...spookygeek
Oct 22, 2002 6:15 AM
Anyone have a link to a stress/strain graph for carbon and ti, all i get in my architecture courses are steel and concrete...
About the bike, it looks to me like they are intending to allow the carbon to only be loaded axial to the member, and letting the Ti handle the rest of the stresses near the junctions, which may or maynot include axial forces and a bending moment or two. That might increase the "strength" of the frame, depending whatever causes it to eventually fail. although from Deans site:
Possess a minimum yield strength of 105 ksi and a minimum ultimate tensile strength of 125 ksi

Now i don't know exactly in what range of KSI bikes are normally subjected too, but 105000PSI is probably more than i could muster.

-Brent
So what problem is all this solving? ;) nmLeroy
Oct 22, 2002 4:18 PM
No mold neededchazman
Oct 22, 2002 7:25 PM
I really do not know a heck of a lot about this subject but do know that making a mold for a carbon fiber frame is very expensive. Furthermore, you have to make one for each size. That is why Kestrel put out the Talon as a two peice bike. The rear is one mold, same size for all bikes, and the front triangle has several molds (bike size specific) which are smaller and much less expensive than a full frame mold. By using TI as a skeleton you do not need a mold. All of the full carbon tubing can be made from one mold and cut to size. Costs more to make each bike but if you are not mass producing then overall you make more profit.