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Amazing, thanks.
So except the comfort/etc issues with running a smaller tyre, I would be more efficient running a 20mm or 23mm on the Kuota, to increase the gap from 2-3mm to closer to 10mm? Currently it's 25mm with the negligible gap, running with the prescribed 'closer-is-better' (that you've disproved).
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It's going to be pretty marginal stuff. I'd go for 23mm rear, looks very tight at the moment.
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'closer-is-better' (that you've disproved)
No, Look disproved it for their frame. Result will vary between frames, depending on the length and cross section of the shear layer. Some seat tube cutouts have a flat back, so the shear layer is only thin at the crown of the tyre. Some have a concave section which matches the tyre profile closely, so the shear layer is thin all the way across the tyre. Some even have a deep groove which gets the frame close to the edges of the tyre for good flow transition from the frame to the wheel, but further from the tyre crown to keep the shear layer thicker in the middle. Things are also complicated by the width of the seat tube; if it's a lot wider than the tyre, you can probably open up the gap more without dropping the flow into the hole. You can guess at what might work, and you can see some of it in the wind tunnel, but really you have to field test to see which combination is faster. If you gain 1W by thickening up your shear layer with a skinny tyre, but then lose 1W in increased rolling resistance, you've just made your bike more unpleasant to ride and no faster :-)
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Kuota
Ah, Kuota Kaliber. My guess is that the leading edge of the seat tube fucks the airflow so comprehensively that anything happening behind it is moot :-)
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I'd ditch the helmet if it took a big knock anyway.
But I need to bend the side plates to gt in on.
I can see myself snapping one off while in a rush at T1.
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Those veiwspeed skewers are very nice.
Can't say I'm loads faster. But they are very nice use.
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Interesting comment from Endura, suggesting they already know how to get >1000m extra for Dowsett if he does a second Hour
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Bullshit
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Bullshit
Please show your working :-)
I don't know how credible such a claim is. What reduction in CdA would be required? How much could you reduce CdA by significantly cutting skin drag on the clothed portion of the body and cutting form drag by delaying flow separation?
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Beyond my ability to calculate. But bullshit.
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I'd be less dubious of that claim than Endura's.
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NoPinz not happy... Was a tweet accusing Simon Smart of copying, but it's been deleted...
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There are legal options for them I presume?
Depends on whether they have a patent, whether such a patent covers whatever Endura have done, and whether NoPinz actually want to waste a load of money pursuing it. I can only find two patent applications by NoPinz, statuses are "Terminated before grant" and "Pending"
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@xavierdisley I have IM Wales in a coupe of weeks and I'm just thinking about final kit choices.
I'll be racing in a sleeveless tri-suit and I was wondering... other than maybe looking a bit of a twit, is there any reason I shouldn't try sticking your ATS strips on my arms? Are they likely to give similar benefits to putting them on my legs (which I'll also be doing)?
If I start them just above the crease of my elbow joint then they are long enough to slightly wrap over my shoulders. Since I'd have to put them on underneath my wetsuit, I'd be worried about them getting wrinkled up during the swim and so I might cut them a bit short so that they avoided my shoulders where the movement of the wetsuit is likely to be greatest.
Do you know of anyone else who has tried this? Is it likely to help?
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I don't think it's as simple as just sticking them on. Body trips have been in development for quite a while but I'd imagine it's something that's very easy to get wrong, same with having them on your thighs.
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one thing I've learnt is you need to put the trips on really early, 1 hour before I put my wetsuit on at the weekend wasn't early enough, and one came unstuck on the bike course....
cant help with the arms, but I suppose it must work in a similar way to the ribbed sleeved suits, so doesn't sound completely silly, and you can always tear them off once you are running to avoid looking crazy for the whole race!
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Ribbed sleeves is a gimmick
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hmmm... maybe. I would try to translate Xav's instructions for sticking the ATS system onto my legs as closely as possible for the arms (e.g. oriented at 45ยบ etc), and they would only be on the vertical part of my arms to avoid them coming loose on my shoulders during the swim. My thinking was that it was unlikely to make me any slower at least... and if they come unstuck and begin flapping then I can easily rip them off and I've lost nothing compared to racing with bare arms.
Actually, am I imagining things or did I see a picture of @Sainsburys_Ed doing this? Edit... maybe not
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Legs are pretty much two isolated cylinders with nothing behind them. Arms affect how air flows over the rest of your body.
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About
Aerodynamics / Aerodynamic Cost / Aero parts
Posted by
@hippy
The air trapped between the tyre and the seat tube cut out has to be sheared, because the boundary layer attached to the tyre is moving past the boundary layer attached to the cut out. The power absorbed in that shear layer goes up as the the layer gets thinner (the drag force is inversely proportion to the thickness of the shear layer for an idealised Couette Flow). At some point, it becomes worthwhile to increase the thickness of that shear layer to reduce that drag even if the resulting gap makes the translational drag of the complete system slightly greater. When Look analysed both the power needed to push the bike through the air and the power needed to spin the wheel, they discovered that a gap of 10-12mm was optimal on their (596 Tri) frame with a disc wheel. This effect is missed in wind tunnel tests which fail to measure the power needed to spin the wheels. Shortly after Look released the 596 Tri along with their explanation for the unfashionable gap, a lot of elite track teams suddenly found some longer chains in their parts bins :-)