The axle probably has high carbon content and will crack with stress. Normally to consider a material of 'weldable quality' carbon content needs to be < .35%. IMO tacking the axle will not solve your issue.I plan to weld the axle to the fork where the drop out is si it dont slip out, and since the bikes weight will be pulling the axle the other way it would be all pressured on the weld spot, just the motor kicking in should hopefully hold. and btw the fork i believe is steel. And i got 4 SLA batteries wired in series right now, 2x 12v 7ah and 2x 12v 12ah batteries
its on two bars that clamp to back wheel rod. have issues with it breaking so im gonig to weld it to side arm when i get chance and add more support, so i have passengersIf you have weld capability, and it's steel, you can probably make 2 torque arms and still use the axle nuts. Might be hard to change a tire otherwise.
Is that rear rack on a hinge, or does it just float around?