So today I went out to start my V2 which has less than 500 miles currently. When I bought it they had the full exhaust installed. No issues for So after starting again it was fine but after temp showed I put it in gear and when to move but she started to idle very oddly and died. Hard time getting it started again but started, so I let it idle for a bit and as soon I reved it about 3-4K it began to sputter again and die. Once again got it started decided to take her out for a quick ride and no issues while out but again lots of backfiring while reving which it has never has done before. Okay so the issue is it seems to be sputtering and dying while at idle. The odd new symptom is major backfiring when reved to 3K roughly and randomly sputtering at idle. Any info, knowledge or ideas of what it is or if it’s an issue I should be concerned about?? Any help is really appreciated, thank you in advance.