Here's an idea: You know that little cover on the top end that says CDI? Take that off, and make sure the pulse gen is alright and the little key hasn't broke, come off, anything. That happened to me once and it took me FOREVER to figure out to look there.
This is my trike. There are many like it but this one is mine. My trike is my best friend, and it is my life. I must master it as I must master myself. My trike without me is useless. Without my trike, I am useless. I must ride my trike true. My trike and I know that what counts is not the amount of miles we ride, but the time we ride together. My trike is human in it's own ways, therefore I will learn it as my brother. I will learn it's weaknesses, it's strengths, it's parts, and it's soul.