Among my favorites have been "wind tunnel data" that compares wheels of various rim profiles and types with... no two wheels with the same or similar profiles. As I understand, the whole idea of aerodynamic dimples is to force the boundary layer to become turbulent immediately, which minimizes the difference in boundary layer pressure between the front and back portions of a moving object. However, aerodynamics is a tall tower of empirical charts loosely glued together with theory, so there are certainly unknown mechanisms happening in every aerodynamic situation. Perhaps their dimpled disc pulls a shielding buffer of air around the top of the wheel, which cascades down and back across the wheel helping to smooth out the drag from the forks. Who knows! They have a chart to say it works and that's pretty much all anyone has. Dimples on bicycle wheels - discussion. The area just behind the forward top section of the wheel is full of spokes, so is already full of turbulence. This suggests to me that the strongest impact on trailing edge drag would be a texuring or VG on the tire, not the rim. Having a wider, bulging rim profile would seem to make dimples more useful than on a narrower rim, but this is more because the wider rim is by nature less aerodynamic than a narrow rim. On the trailing edge as well as on the leading edge. On a disc wheel, the same circumstance exists, except there's a lot more surface area to create surface drag. To my mind, this means that it's closer to resembling an aerodynamic F1 car, which is better with smooth surfaces Additionally, air flow encountering a rear wheel on a bicycle is already very turbulent due to most of the bike and rider being in front of it. Would a dimpled surface be better there or a smooth surface? I'd like to hear some actual engineers weigh in on this. I've discussed this with engineers in the past and I find it fascinating, but hard to find definitive, substantiated answers that I can actually attempt to use actual math to verify. Rim Material 100% Toray Carbon Dimple Wheels Size 700C RoadWheels Rim 45mm/50mm/58mm/80mm Rim Width 25mm aero Rims Weave UD （Default Send UD） Rim Hole 20/24H (Special holes 18-32H can be customized) Hub Black （Hubs offer options） Spokes Aero Spoke or Pillar 1423 Spoke Nipple Alloy Black / Red Nipple type External Nipple Hubs model Straight pull or J-type Spoke Pattern Radial(spoke tension-- 90kgf) Spoke Pattern Non-Drive 2 X Cross(spoke tension-- 85kgf) Spoke Pattern Drive 2 X Cross (spoke tension-- 135kgf) Spoke Nipples Alloy Braking Surface V brake hubs Accessories 1pair CNC skewers(black)+ 2 pairs brake pads Roundness:<=0.5mm Offset:<=0.2mm Max recommended rider weight 135-155 kgs Warranty 24 months Dimples on Bicycle Wheels Clincher Rims 45mm Wheels Detail Picture Show 50mm Wheels Detail Picture Show 58mm Wheels Detail Picture Show 80mm Wheels Detail Picture Show Hubs Parameter Query We use the latest technology to mold, every step is perfect, to ensure the strength of Rims. Buyer please read : We accept payment via Escrow, Alipay, Western Union or PAYPAL. Pease contact us for instructions if you want to pay in other ways or want to buy more quantity. Full payment must be made within 3 days of placing your order. About Shipping： Normally, we ship the goods via EMS or our own forwarder by courier. If clients want the goods to be shipped by DHL, FedEx or TNT, Please contact us in advance. Warranty: All products we sell in our store are in good quality and under strict quality test before shipment. We will try our best to avoid any quality problem. We promise warranty for quality in 24 months. We will repair or replace it free of charge if defective part. was found in 3 months. You will only need to pay the shipping cost if the defects found after 3 months and. This warranty is non-transferable and valid to the original purchaser of the product only. The following improper use will void your warranty. 1 Crashes and accidents. 2 Misuse (off-road riding, jumping, trick riding, Cyclocross, etc). 3 Modification of wheels or Improper assembly. 4 Tire pressure exceeding Road Wheels 115-135psi，MTB Wheels 65-80psi. 5 Normal wear and tear. 6 Improper follow-up maintenance or maintenance by an unauthorized technician. 7 Installation of parts or accessories not originally intended for, or not compatible with the rims as sold. 8 Damage or deterioration on the surface finish or appearance which has no effect on the function. 9 Damages caused by natural disaster.
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