by Squigie » Wed Feb 23, 2022 3:53 pm
I like generous clearances and am setting up the rough road TD for 1.5" sidewall and 2" of tread clearance, at full compression with Timbren suspension. But I have almost 3.5" of travel to consider, iirc. So that is more like 3-4" of clearance for mud, snow, and gravel at normal ride height. (Sidewall clearance is a bit of a compromise, brought on by tire choice and trying to keep overall width as narrow as reasonably possible.) If I was using a solid axle and leaf springs, I would have to allow more sidewall clearance for axle articulation.
But if you want a tight, clean look, and will be staying on paved roads and well maintained gravel lots, you can reduce the clearance to as little as 1/2" with some types of suspension (lateral and radial).
If you tighten things up, keep in mind spring deflection and the swing arm radius while doing the calculatin'. With torsion axles, leaf springs, trailing arms, etc., the axle/hubs are typically going to be arcing rearward as the suspension compresses.
It is all about what you're using, what you think you need clearance for, and how well the fenders fit the tires.