Re: I had a breakdown today...
Ok, lets look to see what might effect it first. 1: pull the spark plug and place it on the top of the motor and see if you have a spark or if it has sufficient spark. 2: check to see if the your getting gas to the system. I had problems with the my carb on my last bike and had to swap it for the earlier one from my first kit. Finally check for compression, borrow a compression gauge and see if you have got a leak somewhere.
I had a similar problem myself I found that I had a bad plug wire so I went down to the auto parts store and got a better one for eight bucks and cut the distributor cap side off screwed in the new one and its worked so far.
Gas-Compression-Spark= running engine, Simple