Internal vs. external cable routing - how aero?
173
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297 days
chekmarks posted 16 weeks ago.
i can't give you any numbers, but i think that the more aero bikes incorporate it. it might not make a big difference but it signifies that the bike was made with aerodynamics in mind. IMO. also, it looks cool.
24
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165 days
kaolelo posted 16 weeks ago.
as you point out, it depends on how competitive you are. the biggest improvements you can make to your bike are your own aero position (a proper fitting), and a good set of wheels. all the other improvements are incremental.
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TriSooner posted 16 weeks ago.
cwalz wrote:
Does having thin cables running the length of the top and down tubes really affect the aerodynamic properties of the bike all that much? Keep in mind here that I'm a 40+ age-grouper who averages around 22mph on my bike legs in Olympic/International distance races so I'm not Norman Stadler averaging 26mph. So much of bike marketing is hype and jargon and I'm just trying to get a realistic sense of whether external cables really has any signficant impact on how areo the bike is.
You seem to have the right amount of skepticism. Seriously, did someone try to sell you a bike by telling you that the internally-cabled frame is more aero? Rich. I'm sure that technicaly, if there were wind tunnell tests that were so senstive as to be able to discern the impact of external 2mm-wide cables, then yes, they will demonstrate a drag effect. But does it have any significant impact? Not a chance. If so, then I need to internally thread my chin strap into my skin.
5
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463 days
giannifive posted 16 weeks ago.
Remember, the rider represents about 80% of the aero drag of the rider + bike combination. Since the bike is 20%, and internal vs. external cabling may represent a 1% difference, we're talking 0.2% overall aero drag difference here, order of magnitude. Is it worth the price difference? Only you can answer that. Personally, since I'm a frugal person, I've ordered all my upgrades by % aero drag improvement per dollar and am working my way down. Internal vs. external cabling, were it on the list, would be far down there. But that's just me :)
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632 days
cwalz posted 16 weeks ago.
Given that I'm going to be averaging even slower speeds during a 70.3 I think I'd be happy to give up 0.2% of my aero drag for a more comfortable ride on aging body. I can try to make up for it by working on improving my aero position on the bike. Thanks!
427
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429 days
Sully800 posted 16 weeks ago.
Internal routing is nice for reasons other than aerodynamics. It gives the bike a cleaner look and also makes picking it up by the top tube easier. If you use a bike rack that attaches to the top tube, internal routing is also very nice to prevent interference.
The cons are that its a little more expensive and more difficult to maintain since you don't have access to the whole cable.
Hey, all--
I'm in the market to upgrade my aluminum TT/Tri bike to a full carbon frame. I'm currently riding the entry level Cevelo Dual which has worked well for me on short-course races but it's a bit heavy (20+ lbs w/full Dura Ace) and the ride is pretty harsh especially on longer (40-50+) rides now that I'm training for a 70.3. I'd like to get the light weight and stiffness carbon can provide along with the more comfortable ride. I've got my eye on what looks to be a pretty decent full carbon TT frame but it has external cable routing (the Cervelo has internal).
My question is this: Does having thin cables running the length of the top and down tubes really affect the aerodynamic properties of the bike all that much? Keep in mind here that I'm a 40+ age-grouper who averages around 22mph on my bike legs in Olympic/International distance races so I'm not Norman Stadler averaging 26mph. So much of bike marketing is hype and jargon and I'm just trying to get a realistic sense of whether external cables really has any signficant impact on how areo the bike is.
Thoughts and suggestions are appreciated.
Thanks!
-Chris