Take a look at the needle measurements in the pics in this thread.
http://www.honda305.com/forums/viewtopi ... 7&start=30
If you needle is not the same length as shown, it is probably either broken off or someone cut it off for some unkown reason???
It's hard to imagine anyone accidentally breaking the needle at that location.
I'd recommend getting a carb repair kit, which will give you a new needle, gaskets, air and throttle screws, and a float valve. (you will also get new main and slow jets, but I would just re-use the old ones) thery are available for 15-20 bucks from several vendors.
If you use that needle you have with the clip in the top groove, it will still probably be a little on the rich side...but it should still run.