I just purchased a Sportster today, it is a 1993 frame and suspension and a 2000 evo 1200 motor. The guy I bought it from said he was on the freeway when it started acting funny, and thought that the diaphragm in the carb had a hole in it. We replaced the carb with a good one and got new sparkplugs for it. It is getting spark and slightly turning over, it will run for a few seconds then die, but it will blow out black smoke when it starts. I live in Utah and the guys at the HD shop said the jets were to big, I don't remember the size tho, so could it be that its running to rich to start? I'm not very savvy with engine work at the moment, so I don't really know what is wrong with it. Any help would be greatly appreciated.