A bit of advice if poss, I have a WR250F 2004 which has a stutter right through the midrange in all gears. I have tried it running on choke to see if its full but my mechanic and the local yamaha dealer both think its ignition. I have heard that this is a common fault caused by the ignition coil bit as its an expensive test to buy I thought I would ask the collective on their views.
Fuel is new, carb has been cleaned and new jets and needle fitted, valve clearances shimmed and timing checked.
Ta
Fuel is new, carb has been cleaned and new jets and needle fitted, valve clearances shimmed and timing checked.
Ta