I just bought me one of these beauties and brought it out of long term storage. it was definitely properly stored as far as I can tell. but on cold start up it will do this weird hiss thump noise from under the gas tank a couple of times and then go away. it also did something weird the other night when I decided to take it to redline for the first time since waking it up the speedometer cut out completely and it started to run really rich. back firing and wouldn't idle I did manage to get it home. so when I woke up this morning and started it up it did the hiss thump thing again but it has since ran perfectly... anyone have any Ideas. Thank you in advance!!!