There are various ways of attaching the wheels of the car so that they can move up and down on their springs and dampers , and do so with as little change as possible in the distance between adjacent wheels or in the near-vertical angle of the tyres to the road.
The most loop-the-loops in a Hot Wheels track is 10 and was achieved by Rohan Dayal and Rahul Dayal (both India) in Mumbai, Maharashtra, India, on 7 April 2021. It took Rohan and Rahul three days to build the adjustable angle wooden platform and assemble the entire track of 10 loops over it. Two people were involved in the project. Rohan Dayal and his younger brother Rahul Dayal. "Testing was initially with few loops and as we increased the loops and the length of the track, the project became challenging. Since the track became long it needed to be supported on a firmer wooden platform. The longer the platform, the greater was the weight and bending in the center. This needed strengthening of the platform. This was the initial challenge." While testing the brothers found that the journey of the car through the loops depended greatly on the angle of the platform. To facilitate variable angles they had to construct an adjustable wooden leg support. By adjusting the leg support during testing they arrived at the best angle which gave them the breakthrough that they could achieve the target. The project cost approximately INR 3500 ( approximately £35). The cost was less as the brothers already had collections of Hot Wheels cars and track and only had to purchase the remaining missing track pieces. The plywood used for the platform was upcycled from scrap. There were a numbe rof challenges faced by the pair. As the number of loops increase, the project became challenging in terms of scale. The length of the platform, it's weight, and height also presented difficulties in handling. The speed of the Hot Wheels car increases as it descends from greater heights causing the car to lose balance. Despite all these difficulties the pair think they could attempt to increase the loops by a further one or two in the future. "Since a young age of around 12 years, I would try to do small projects like making a wooden toy car or cricket bat. Later as I grew I would do some small household repair works. For all this, I would use my Dad’s tools. As a child, I liked playing with toy cars. I would make my wooden toy car and make it slide on sloping surfaces. During this time I was gifted with Hot Wheels cars and tracks which came with super smooth cars and steep sloping tracks. Soon I had a good collection of it. Recently I came to know about the Guinness World Record of 8 loops and decided that I can better the record. The Guinness World Records titleholder would be the best thing I would have ever got. It would also mean that records are an inspiration to do better and create greater records. It would be a proud moment for both me and my family."

Double wishbones are used mostly at the front. There are two wishbones, one above the other, to keep the wheel upright as it rises and falls.
I was gonna make a snarky remark about damping, but if that setup provides <1.5" or so of suspension on a commuter bike, it's probably a good thing. Max on April 14th, 2013 - 5:58pm