Team Magic G4RS & G4 Setup
We have received many emails about the G4RS and G4+ handling issues in regards to too much steering / loose rear grip. This is especially prominent when the Kfactory tires are used. This is a sample of the emails we receive:
Damn...those tires a lot of traction. The only problem I have is the 38 front is too much steering for me. I had to used jaco for front 40 and that settle my rear end. I came 2nd on sportsman due to couple mistake. All I can say about the g4rs "fast and easy to drive" I was able to drive tighter lines. And one of the expert driver going to get one (g4rs). He could not believe how good the car is
The reason why this happens is that the suspension on the G4RS and G4+ is a true advancement in R/C technology. The longer arms allow the suspension to remain consistent over their range of travel. This allows the front tires to grip much better than any previous (or current competitor’s) chassis design. As a result the slip angle is greatly reduced. For those of you who know what slip angle means, skip the next few sentences. Slip angle is the difference between the direction that the front tire is pointed in a turn and the actual relative chassis motion. As an example your tires may be turned 30 degrees but your car is only turning at 15 degrees. This would be a 50% slip angle. With the new flying wing suspension the slip angle is GREATLY reduced. I don’t have the equipment to actually measure the exact number, but on my transmitter I reduced my steering travel from 92% to 64%. So you may be asking, “If the suspension is so great why does the rear end snap around Unless I change to harder tires in the front”? The answer would be obvious if you were driving a real car and had this situation. The rear grip problem is a result of “relative servo speed”. I’ll exaggerate a little in this explanation. If you cut the steering servo travel in half and don’t change anything else to achieve the same result, you effectively double the servo speed. When you dialed out the steering travel in your transmitter you reduced the total travel so it takes the servo less time to get to the end point. If you still turn the wheel on the transmitter like you were when the servo was going farther, then the front wheels change direction so fast that they are “shocking” the suspension loose on turn-in. What make this so drastic is that the reason for the reduced servo travel is that you have so much more grip from the tires because they are not sliding as much. The cure for this is really simple. When you dial out steering you also need to slow down the steering servo speed setting on your tranmitter or slow down the rotation of the wheel on the transmitter. The latter is the overall better solution since driving smoother is the way to go. In testing, every time we slowed down the servo speed we were able to use the softer fronts without losing the rear grip.
One other question we get a lot is: “What are the ratings on the different springs in the 502143 spring kit”? And "What is the rating of the stock springs"?
1.2mm 10lb
1.3mm 13lb
1.4mm 17lb
1.5mm 20lb
1.6mm 26lb (stock and aqua springs)
1.7mm 31lb
1.8mm 41lb
1.9mm 51lb