New guy to the forum, Just purchased my 74 CB 750 from the original owner, he was a wonderful guy in his 80s that just had a hard time letting it go. He would start the bike often but it had not been ridden for years. I have had the carbs rebuilt and syc. replaced the plugs and coils and wires and all full lines and filters. The bike starts up and idles just fine. When you attempt to ride the bike and put it under load it pops and misses badly. I am not sure if I am dealing with a spark issue or a fuel issue, I have ordered a new petcock to make sure if I am getting a good fuel flow. any ideas on what to try next would be great. The bike looks like it did in 1974 complete with windjammer. I have attempted to put the bike back in its original state.