My bike is a 87 SP200. It is all stock. It started messing up and cutting out the other day while riding in the yard with my son. It had been in storage for about 8 years when I got it back in March. I cleaned out the carb and did other necessary things to get it running. I took the carb back off and cleaned it really good. I did't see anything that looked like trouble floating around inside. I replaced the carb and it's still not right.. it idles like a top but when you touch the gas it dies. I replaced the plug and that didn't help. I've taken the carb off about 3 times and sprayed it, blown it and done everything I can to clean it. Still the same stuff. It is a Mikuni BST 32 flatslide.. if the diaphram has a leak will it cause this? I'm a honda man so I'm used to working on Keihin carbs.. This is my first Mikuni. I'm about ready to set fire to it. Thanks for any help!