JinLun 125-13 wont start?

I have had the bike sitting for just under a year as I have no need of using it as I am on a bigger bike but wanted to get it running for my other half who is now ridding. I had it ticking over I say about 8 months ago and no problems. I took the exhausts off to clean them and paint them to stop them from rusting. I put them back on and now the bike just wont kick over. The only way I can describe it, its like the battery is not charged, I have had this problem in the past and put a new battery on and sorted but this time its not worked. It runs all the lights fine and I even used the same voltage battery from my other bike. When you press the start button it whines at me like a dead batt, I did get it to kick over once but it sputtered and then nothing. For the time after that I had to hold the clutch in for it to kick over and then that was the last time it would start. I have checked the fuel and its clean, put redex in and drained the carbs in case there was gunk in them. I am just not sure what could be wrong with it, electrical or carb problems. I dont want to start taking the carb off if I dont have to as I know they are touchy bikes. Just at a loss and have been trying to get it working for three months and losing my patience with it now.