Throttle not working

OK, so hopefully you guys can give me some insight as to what my problem is..........my bike has still not been completely ready for riding yet, although I've taken it for a few test rides around the block. I have a Broped 80cc kit.

My throttle cable just broke, and I replaced it with a new one. My throttle worked before, but now, nothing happens when I twist it. You might think that the new throttle cable isn't hooked up properly, but I am pretty sure it is hooked up correctly. The throttle handle twists back, and it pulls the cable to open the valve in the carb just like it is supposed to.

The engine kicks in when I release the clutch to start it, but nothing happens when I twist the throttle. Hunter from Broped said to check the wiring, which I did, and I'm pretty sure that is all connected good as well. Unless it is something inside the ignition box?

Hunter also said it could be the Chinese spark plug.....I looked at that, and it didn't look burnt or anything like that. I was told to buy an NGK B5HS, but the tip of the B5HS is a little different, and it won't fit in the connecter.........ANY ADVICE ON SPARK PLUGS OR IDEAS WHAT THE PROBLEM MAY BE?

Thanks guys.

maybe I should try a new spark plug boot (& spark plug)?

yeah the engine would start up and idle for a second, and then die because the throttle wasn't doing anything. Actually, the throttle was working the other day when I took it for a test ride, though it took a few seconds for it to respond. I checked the valve again, and it is working fine. I think maybe the problem was that the little switch on the carb (don't remember the name for it) was not all the way down.....? So it was running for a few seconds until the chain came off to due a totally different problem. But hopefully the throttle is functioning correctly now.

oh don't worry, I'm not about to throw in the towel...I literally NEED to get it running so I can find work, haha. This is my first time building one of these bikes, so some setbacks are expected (actually, Murphy's Law has taken effect during the course of this project).

noco: I'll check the pin assembly again to make sure everything is put together right.
Hillbilly: are you saying the choke level should be up when I start it?

And for the chain issue, I was talking about the engine drive chain. it's actually more of an issue with the tensioner than it is the chain. There is already a hole with a bolt through it to hold the tensioner to the frame, but maybe I drilled the hole too soon. i've had to change the angle of the tensioner and add washers to get the wheel to line up perfectly with the chain. But obviously it still wasn't 100% secure because the chain pressure pulled it inward and it got caught in the wheel spokes, tearing the wheel off and a spoke as well....

So now I have to order another tensioner, and won't be able to try it again for a few days...