Damper, Locating 1
1FK-21778-00-00
Retail Price: $6.99
Your Price: $5.67 part #10
There is another damper at the rear of the left scoop in the fiche picture, it's part #12 but is not labelled as such in the detail pic I took a snapshot of.
Damper
1FK-21747-00-00
Retail Price: $24.99
Your Price: $18.02
I suspect
Vinmax has a good deduction on their special purpose. Remember that the vehicles have to meet various standards, and noise is one of those. Especially intake noise, hence, the Helmholtz resonators on many induction systems on cars, bikes, and trucks.
https://newt.phys.unsw.edu.au/jw/Helmholtz.html
The Buells had models (Thunderbolt, Lightning) with a huge, unsightly Helmholtz resonator on it, and anyone who removed it soon realized that it had multiple purposes.
It quieted the induction noise down, and it also aided the bike's performance. Those of you who have large air compressors may have one on your air intake, which significantly quiets the noise of the operating compressor.
Those of you with a need for the math behind it, can go here:
https://core.ac.uk/download/pdf/4956902.pdf
If you read all the daily posts, you may have seen
jack hammer's custom VMax. Look at the exhaust, and you can see that round 'sideways' canister on the exhaust pipe in-front of the end of system canister. That appears to be a Helmholtz Resonator. The exhaust looks to be a Yoshimura, judging from the exhaust canister's '3:47' lettering, Japanese characters which resemble the Arabic numbers 3:47.
Planes and F1 cars pay special attention to aero characteristics. A slight modification can increase the attraction of the F1 car's body to the roadway, where the car acts like a suction cup, providing additional cornering abilities for the car to negotiate the circuit faster. Older fans of sports racers may recall the Chapparal of Midland, TX's Jim Hall. He used two two-stroke fans in the rear panel of the car's Kamm-design tail, which evacuated air beneath the car, which created a lower density of air beneath the car.
That caused the car to pull itself down onto the road surface, and there were sacrificial, movable body panels along the sides of the car which helped the sealing happen. It worked surprisingly-well. So-well, that other builders tried to copy it, and the racing governing body soon outlawed the principle and its application. Jim Hall was also famous for creating the huge rear of car wings, commonly referred to as 'spoilers,' to increase traction at the rear of the car. Hall's design, wasn't just a static wing, it was moveable, and it connected to the suspension, so the loads were directed so they would do the most good. Today's F1 wings are also 'dynamic' in their function.
https://www.roadandtrack.com/motorsports/a32350/jim-hall-chaparral-2j-history/
I mentioned the 'Kamm-Effect' before, that is a very simple, elegant way to improve the aero performance of a car. Before WW II, aero scientists believed that the shape of a raindrop, as it became semi-spherical on its leading side, and tapering to its trailing side, was a good use of aero design. Kamm determined that to achieve a similar result in a car or motorcycle, you merely 'chopped-off' the rearmost tapering portion of the shape, in a vertical 'slice' leaving a vertical flat end of vehicle shape. This design cuts-down on excess weight and length, and reduces aero drag. The purpose of the long tapering tail was to allow a gradual joining of the boundary layers of air across the shape of the body, as they approached the rear of the car. This was how aero drag was minimized. Check-out the aero helmet, and his 'fart-collector.' 1936 BMW R5, aero add-ons to the intrepid rider done in-search of additional speed.
Georg 'Schorsch' Meier, called the 'Cast-Iron Man,' who won the Isle of Man Senior Tourist Trophy in 1939, after winning the European Championship in 1938 on a supercharged BMW.
Ernest Henne was the fastest human on a motorcycle for 14 years on his BMW Kompressor.
Note the German National Socialist party's 1930's insignia on the tail, when they were involved in all sorts of competitions to prove to the world the greatness of their engineering exploits. The record would last until 1951, long-after the Third Reich was destroyed.
Kamm's solution, the vertical direction 'slice' of the tapering portion of the body, caused minimal additional drag, and it allowed the car or motorcycle to be shorter, lighter, and yet still have good aero drag and performance.
https://www.superformance.com/factory-models/shelby
In the 1960's while racing at LeMans Ford discovered that their Cobra roadsters which were hellaciously-fast on acceleration, would become alarmingly light and unsteady as speeds went over 150 mph. Attempts to change the shape of the roadsters to lessen the scary aero lack of performance of the roadsters above 150 mph was unsatisfactory, so a Shelby Cobra employee, Pete Brock, was tasked with developing a new car to combine the performance of the Shelby Cobra roadsters, but with the aero dynamics to maintain control down the mile-long LeMans Mulsanne straight. He came-up with the Cobra Coupe, one of the most elegant and successful designs ever to enter LeMans. It also won the world sports car championship. Only a few were made, and it was very-much a purpose-built car which did exactly what it was built to be: a strong-performing car with superior aero packaging, which was easy to control as speeds approached 200 mph. The original cars now sell for many millions of dollars, and replicas can be built from kits resembling the original design, but with improvements in tires, brakes, suspension and powerplants found today. Plus, they are much-less expensive!
The Ford GT40 was another 'clean-sheet' car which Ford commissioned, a mid-engined car where the Cobra GT Coupe was a traditional front-engine/rear wheel drive car. It (GT40) was based upon a design done by Eric Broadley, the Lola T70, which was a successful mid-engined 1960's car which was raced.
Looking at the tail of the Cobra Coupe above, you see the Kamm Tail shape personified. The Ferrari P3/P4 also used this design. Mid-1960's racing design at its best.
