Is the bike new to you? I might suggest a carb rebuild. I purchased a kit off ebay years ago and did it myself. Wasnt to bad after getting the carbs out. If I recall putting them back in was a bugger but it ran great afterwards.My 88 gl1500 carbs aren't working properly. Cyls. 2 and 4 are receiving fuel, 6 is. When I spray cleaner into the left carb the rpms jump up. Originally 2,4 and 6 wasn't firing. #6 picked back up after using the cleaner (I think).