I have a 1998 vn750. I have had it for a year, and have put about 5k miles on it. I have pulled the carbs three times in the last year. A week ago I was riding to work and the bike had a loss of power and a loud banging and scraping noise came from the engine. When I purchased the bike it had a salvaged title and I believe a previous owner has down some work on it. I am concerned that it is a piston or a rod and that the engine will need to be rebuilt. Any ideas if I am thinking in the right direction? If it needs to be rebuilt does anyone have any ideas of how much it would be for me to do myself?