have a 2002 sv. rode home fine yesterday from work. this morning the bike was really hard to start. it is spluttering heaps and almost backfiring. it only idles when choke is on full. i only just made it to work this morning. when i accelerate it splutters and there is little power. every now and again power comes in (and nearly sends me into the back of the car iam following) and then drops back out again. any ideas?