I see two positions when it comes to the topic of springs for spring mounting. The first says that the force of the spring is irrelevant; it only holds the threaded rod in position anyway.
In the second group, a great secret is made about which feather to use and which not to use.
Here's a conversation I had with Jens B. on this topic. I think everyone can glean information from it and decide for themselves which type of springs they want to install.
Jens says there's no right or wrong answer! That's just the disadvantage of a simple spring frame. "Off-road, you don't need the springs, or they can even be a hindrance. On the road, you definitely need them. At least in dangerous situations. A quick swerve and the frame lifts off the ground. That can even be dangerous. Now it's up to you! What do you want? Safety on the road = the stiffest springs you can find. Freedom off-road = no springs. What's the balance between off-road and on-road riding? Of course, you could also consider simply removing the springs for off-road use."„
And further: „You won’t find a formula for the springs anywhere. And no one will be able to tell you for sure. There are just too many individual factors involved. You simply have to try it out! A development engineer will be able to simulate it with the appropriate software. But I don’t even want to know how much that would cost!“
„"People always say 5 cm per body length. But that's not really correct! The correct amount is 5 cm per meter between the fixed bearing and the spring! It actually makes sense. The overhang is completely irrelevant! If necessary, you can pre-tension your springs a little and reduce the travel to 12 or 10 cm. A little pre-tension is generally a good idea on the road anyway. But you only adjust that when your vehicle is fully loaded."“
Jens also says it is important that the fixed bearing at the rear is screwed in tightly, but should still have about 1 mm of play in the screw holes, otherwise the screws could shear off if you overlook a pothole or if there is a heavy impact into the cabin for another reason.
