1500 Vulcan engine vibration
Well I am finally back with the results of my most recent test & inspections. Here is where I am.
First, I could not stand the loud noise from the Vance Hines 2 into 1 pipes that were on the bike when I purchased it, so I found & ordered a complete factory exhaust system and changed that out. (Now I can once again hear), but that had no effect on the vibration problem. Next I checked the voltage at the coils and did resistance checks and they are both OK. Today I removed the carb, disassembled and cleaned. Both jets are stamped FTC for factory installed, a 142 & 45. Cleaned both with tip cleaners, checked float level and everything else. All OK. Reassembled and started. Engine idles fine but as I begin to give a slight amout of throttle, vibration begins and continues up to the high RPM range. When trying to ride is very uncomfortable as it vibrates all the time.
New observation: When I first started engine before connecting crankcase vent lines to air filters I noted a lot of pressure & vacuum from these hoses. After connecting all lines and putting everything back together, I started engine and unscrewed the oil fill cap. There is pressure, vacuum as if I have a direct cylinder leak into the crankcase. I understand there is a decompression feature on the front cylinder for cranking purposes. Could this be stuck in an open position? Is it supposed to close after starting?
Thanks again for any suggestions.