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A2WindTunnel
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« on: November 18, 2008, 09:10:19 AM » |
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If anyone is interested in Bicycle Aerodynamics, here is a recent article about A2 + Specialized and a collaboration we did with wind tunnel data and how it correlates with on-track data. Pretty interesting aero article weather your into bikes or not. But it can illustrate the time and power savings by optimizing the rider into a more aero position while allowing them to produce efficiant power, and while they measure power in watts, it is the same as how much HP they are saving by reducing the drag (1HP = 746 Watts). 70-90% of the power these riders a putting out is just to overcome the air resistance, and any reduction in drag adds up to big time savings over a x-distance race. By optimizing the position of this rider, his reduced drag and added speed would cut off 24min-58sec over an Iron Man distance race which are won by seconds (180.2km or 112miles). This post is just intended to help people understand a little more about how wind tunnel testing could be beneficial and how reducing the aerodynamic drag is like adding HP. I know that bicycles have nothing to do with what you guys are doing (so please don’t blast me), but AERODYNAMICS have everything to do with what you guys are doing and the records you are trying to set. I am working on more stuff that would directly relate to LS racing and hope to have a video up of a wind tunnel test (A2 in house study) to show changes, and data with instruction to demonstrate what a typical wind tunnel test is and how we view at the data to see what is helping and what is hurting the vehicle. http://www.bikeradar.com/news/article/how-aero-is-aero-19273 |
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fredvance
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« Reply #1 on: November 18, 2008, 10:44:14 AM » |
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Do they have one of those helmets with snell rating/  |
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WORLDS FASTEST PRODUCTION MOTORCYCLE 213.470
Vance&Forstall Racing
All 9 SCTA 1350 NA records
WOS 2011 235+MPH
Engine by Knecum, Tuned by Johnny Cheese.
Sponsers Catalyst Composites, Johnny Cheese Perf, Knecum Racing Engines, Murray Headers, Carpenter Racing
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Seldom Seen Slim
Administrator
Hero Member
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Age: 64
Location: Skandia, Michigan
Posts: 7322
Nancy -- 201.913 mph record on a production ZX15!
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« Reply #2 on: November 18, 2008, 11:02:26 AM » |
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Fred-
Well, the Snell folks would probably take issue with the pointy thing in the back, don't you agree? Maybe if we submit the helmet to the rules and the safety committees -- and then also promise to wear a back protector and even maybe fashion the aero pointy part out of a breakaway material -- then perhaps. . .
I've ofter seen those bike helmets and wished there was a motorcycle racing version. Not yet, I'm afraid.
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Jon E. Wennerberg
a/k/a Seldom Seen Slim
Skandia, Michigan
(that's way up north)
2 Club member x2
Owner of landracing.com
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fredvance
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« Reply #3 on: November 18, 2008, 11:18:01 AM » |
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Yeah, they are funny looking but if it was good for a mph or 2 I would wear it.
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WORLDS FASTEST PRODUCTION MOTORCYCLE 213.470
Vance&Forstall Racing
All 9 SCTA 1350 NA records
WOS 2011 235+MPH
Engine by Knecum, Tuned by Johnny Cheese.
Sponsers Catalyst Composites, Johnny Cheese Perf, Knecum Racing Engines, Murray Headers, Carpenter Racing
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panic
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« Reply #4 on: November 18, 2008, 11:28:46 AM » |
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And make the back protector into a tail...
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A2WindTunnel
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« Reply #5 on: November 18, 2008, 01:53:22 PM » |
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Believe it or not, all helmets are very specific to each bicycle rider and is the same on motorcycle riders as well. This is because of body size and shape and positioning on the bike. The bike and rider are a system working together and the air interacts with both. One helmet might work well for one rider but not another. Just look at all the different back shapes. One guy might have a flat horizontal back while another has a curved hump on his back. For Motorcycles, a helmet and or a back protector in the right position and configuration for bike and rider would have great benefits in drag reduction if you could minimize the gap from the helmet and the back and also help transition the air down your back to try and keep the separation from the helmet to a minimum. You would also need the windsheild to transition on to the helmet well. Here are 3 different back types you can see for yourself the difference and how it could apply to motorcycles and positions.    |
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Stan Back
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« Reply #6 on: November 18, 2008, 02:03:10 PM » |
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How do butt cracks figure into this?
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Member of the San Berdoo Roadsters – California's most-exclusive roadster club.
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landsendlynda
Hero Member
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Age: 61
Location: FOUR! Count 'em 4 miles from the salt!!! Life is Goood!
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« Reply #7 on: November 18, 2008, 02:14:13 PM » |
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Creates whistling in the wind.
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Volunteer roadblock at Land's End! Yes, you need your stinkin badge! I'm your Dream Keeper, I protect your dream on the asphalt so you can chase your dream on the salt!
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fredvance
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« Reply #8 on: November 18, 2008, 02:17:43 PM » |
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I still like Rollie Free's full layout and speedo.
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WORLDS FASTEST PRODUCTION MOTORCYCLE 213.470
Vance&Forstall Racing
All 9 SCTA 1350 NA records
WOS 2011 235+MPH
Engine by Knecum, Tuned by Johnny Cheese.
Sponsers Catalyst Composites, Johnny Cheese Perf, Knecum Racing Engines, Murray Headers, Carpenter Racing
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Glen
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Location: South West Utah
Posts: 5130
SCTA/BNI timer 1983 to 2004,Semi Retired,.
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« Reply #9 on: November 18, 2008, 02:45:53 PM » |
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Glen  South West, Utah |
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1212FBGS
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« Reply #10 on: November 18, 2008, 03:04:19 PM » |
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the windscreen has to stop at the front of the helmet and can not wrap around the sides
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Glen
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Age: 76
Location: South West Utah
Posts: 5130
SCTA/BNI timer 1983 to 2004,Semi Retired,.
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« Reply #11 on: November 18, 2008, 03:10:26 PM » |
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I wonder if Butt Crack Putty is allowed for additional streamlining and stops the whistling?  ?  |
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Glen South West, Utah |
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landsendlynda
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Age: 61
Location: FOUR! Count 'em 4 miles from the salt!!! Life is Goood!
Posts: 880
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« Reply #12 on: November 18, 2008, 04:05:43 PM » |
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Seems to me, if the speedo's are tight enough, canyons would be welded together with no chance of wind velocity.
Lynda
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Volunteer roadblock at Land's End! Yes, you need your stinkin badge! I'm your Dream Keeper, I protect your dream on the asphalt so you can chase your dream on the salt!
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McRat
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Location: Norco CA
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Diesel Hotrodder
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« Reply #13 on: November 18, 2008, 04:14:45 PM » |
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Fred-
Well, the Snell folks would probably take issue with the pointy thing in the back, don't you agree? Maybe if we submit the helmet to the rules and the safety committees -- and then also promise to wear a back protector and even maybe fashion the aero pointy part out of a breakaway material -- then perhaps. . .
I've ofter seen those bike helmets and wished there was a motorcycle racing version. Not yet, I'm afraid.
Maybe you could pack a parachute into it? Kidding...  |
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Pat and Kat McSwain - DT 1616 "Casper" 2005 GMC 2500HD Sierra 4x4 Duramax Diesel + Allison Transmission B/DT & A/DT record holder, El Mirage (163) & Bonneville (175) Best clocking 197.068 mph - Bonneville '09, 2.25mi www.duramaxdiesels.com |
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A2WindTunnel
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« Reply #14 on: November 18, 2008, 04:16:14 PM » |
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I know that there is a rule on where the windshield ends, but you want the shape to match your helmet the best you can or have a smooth transition. I other words, you don't want there to be 4" of windshield sticking out from each side of your helmet and you don't want a helmet sticking 4" above your windshield. Plus, you do have to have your head in a position to see where you are going. PS: The butt crack whistle is not as bad as you might think. Good smooth transition from windshield to helmet  Head could be lower  This guy alone could benifit from a better position. Small HP means Aero is VERY important for his top speed.  windshield appears too short for that rider  |
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