New to the concept, but definitely having fun building this. Still have some work to do (disc brakes, better tensioner system, wide crossover stand, drum up the nads to ride it), but I think I’ve navigated a few of the mismatches and frustrations.
Back tire wear is a lot faster than pedal power. The Hookworms are great tires as long as you use down hill tubes. I have a kenda dh in the back. It's something like 2.35mm thick. CST Cyclops are also great tires according to some well respected members here and the other forum.
Looks good!
As far as suggestions, the 4-bolt tensioners do better on those small tapered chainstays than the older single 2 bolt style since one side can tighten more than the other to make up for the taper. The stock bearing doesn't last too long in them anyway and most replace it pretty quickly with a better cover mounted spring loaded setup so just something to keep in mind.
The pull starter was notoriously unreliable but apparently recently a new version was released which addressed some of the issues...not familiar enough with them to tell the difference from a picture but if I were you I would try to see which version you have. If its the older one, might be good to order a replacement now to have on hand in case of any issues in the future.
Also, the kit chain guard on the motor chain is damn near impossible to keep firmly in place in a usable area so expect a lot of rattling and coming lose from it. Might be worth removing unless you get caught in mud and rain often.
Have the studs for the stock exaust gotten that good to free float the muffler and not rip out? I know you guys have had issues in the past. Tom