Does anyone know where the idel screw is on my 87 VR. I have looked for it and I am having trouble finding it. Is it a thumb screw like in the manual or a slotted screw? Also ,how would I be sure all 4 cylenders are firing? Will it run on 3 cylinders without notice except loss of power? The reason I ask is the scoot sat up for 6 years before I woke it up and seams to run smooth but I dont know if all cylinders are fireing and idels so low it cuts off when throttle grip is at idel position. Any help would be great. Thanks!!