the double banjo is to help disperse the fluid more evenly. with the center ridge on the double blot it will block the fluid. I have seen that banjo bolt used on honda motorcycles.
Good Luck
the av gas will work you just have to re jet because the fuel is oxygenated. What size jet are you running? it sounds like you are running it lean. Detonation and running hot are a sign of a lean condition.
LMAO
Just go to your local hardware store of auto parts store and get a tube of blue loctite. it is a thread locking compound. That will help your bolts from working loose.
Nothing wrong with the plastics it is the fasteners...
does the fuel flow out of the petcock? does it make a difference if it is on reserve or not. Is the fuel on? Is there gas in the tank? There are two filters on the petcock in the tank. you might have to remove the petcock and clean the filters.
there is 3 thing an engine needs in order to run. Fuel, compression and spark. I'd start off with new plugs. If that does nothing than run a compression test. If that is good (no variance above 10%) than check your fuel system out.
There is a little black box next to the coil. That is the TORS controller. make sure that is unplugged. If you can not unplug it "cut it". Than shrink wrap the wires and make sure none of them connect with another.
Bandaids don't last. You have to split the case to make sure all the shavings are out. Splitting the case is not hard but most are afraid because it sounds hard. Take your time.
Good luck
I have heard nothing but bad things about the cdi boxes with variable timing. Definitely swap back to the stock and set your timing to 5 degrees and make sure your pick up has a 0.020 in or 0.5mm gap. Did you reuse your old spark plug boots?
the backfire is most likely a lean pop. How do your plugs compare? if one is light and one dark than you have an air leak. If they both are light colored than you have a jetting problem.
Good luck.