appreciate the videos, but maybe less talking, more action? it takes you a little longer than needed to demonstrate simple steps. i think the videos are a great way to show your work, and possibly help other karters with some of the basics. but just as with any drawn-out documentary style video - too much talking and not enough action can put a viewer to sleep. lol. "now i'm going to open a box. the box is made of cardboard. i will use a knife to open the box. i will place the knife on one end, and slide it to the other end. then i will open the box. i will now look inside the box. inside the box i see some things. those things may or may not be important. but for this video they will be important. maybe...". lol. hopefully you get my drift. maybe throw a hot chick in the video once in awhile? lol.
also, the axle stubs being that long will cause problems. physics from the tires being so far from the king pin will eventually bend the front of the kart in ways you don't want it to, especially after hitting a few hard bumps. your little springs won't help much with those hard bumps. the C-brackets should fit INSIDE the rim of the tire, so that the tire can be much closer to the king pin bolt. i don't see any steering geometry either. the C-brackets SHOULD be leaning back and in (slightly), to help with high speed stability and cornering and steering. don't forget to use Ackerman for proper steering angles!
are there bearings inside the front tire rims? you don't want bare metal rubbing on bare metal, especially at high speeds continuously.