91 trx300fw with chip in cylinder head what to do

I would say if you re-lap the valves you would be ok , check the valve stem for being straight and not bent -----can't imagine what caused that dent , did you have timing chain slack

Retro , I am usually with you 100% , but this time I am going out on the limb to say that is not a stake mark , they are two smaller marks also and no rhythm to the spacings of the mark , you would think if staking was the purpose of the marks , the stake would have used a pattern of a triangle or square ---------- I would guess the engine had a stretched out timing chain at one time , maybe the electrode broke off the spark plug , or it could have happen when the head was dropped or stored in a box when the engine was previous part ---- CSI New Orleans