Have you checked to see if the throttle slide is in the carb properly? With my Grande, I had a similar problem. Carb was clean, points were fine and had spark but didnt start. I checked and saw that the throttle slide was out a bit, fixed it and it fired right up. You can easily tell if this is the issue by twisting your throttle... Also, take out your sparkplug and put some carb cleaner or a little pinch of gas in there and try and start it up. If that works then you can eliminate a few items. Wish you the best!