Some of you have bandied about the choice of various metals for crash protection bars. Aluminum too weak, Hard to weld and repair. Stainless: various alloys with various strength. Harder to weld. Mild steel, cheap and easy to fabricate. Easy to weld and repair. This is the metal of choice for many aftermarket bars and mounts for those reasons. BUT it is about 63,000 PSI and to get the needed strength the parts are made with thick walls and weight goes up. The best stuff for guards, mounts and any structural part is 4130 Chrome Moly. It is readily available, welds and forms well and is rated at 2x mild steel -125,000 psi. It weighs exactly the same as mild steel per cubic inch. You can use smaller diameter and thinner wall tubing and save a lot of weight. I have used this for my bike guards, center stands, pannier mounts and luggage racks for years with 0 failures. This is the only steel we use to weld aircraft fuselages.