Problem fixed.

as per the instructions the split washer that I could not remove from the bolt should not be there, and because I was put the bolt in from the front (as per the instructions) that split washer was on the side where the light mounts. when I turned the bolt around so the nut was by the light and the split washer was between the forks it worked perfectly.

I am installing the headlight on my new bike and as the manual says I out three washers on the bolt, put the bolt through the fender mount, then through the head light, then trough the fork, then one more washer and the nut on the end. but I have tightened it to the point that the nut started to slip in the wrench but the headlight will still slight all over the place with almost no effort.

anyone have any tips on how I can fix this?

for any rad bike that has the new split screen setup, including the Rad City 5 Plus, you need to get the settings menu first by pressing and holding the down PAS down and the light botton for about 5 seconds. While you have the menu open press and hold PAS up, PAS down and the light botton all at the same time and hold for about 10 seconds. (tip: once you get to the point it feels like it wont work, hold for just a bit longer.) At this point you can change the speed and if you press the light botton on its own you can change the watts as well. press power to leave the menu.

I live in Canada so it only has a watt option for 250 and 500. I am curious if the US version has those options and 750. If so then there must be some way for the rest of us to unlock 750 as well, we just need to keep looking.