Hey there, I have a friend who complains about massive headshake on his '09 RMZ 250. I offered him to take a look into it. For him to get it done, for me to gain knowledge. So here's the problem: His bike ist stock, he is 5'9", weighs 145lbs, intermediate rider, only hardpack. When he shuts off the gas in 4th/5th gear, the headshake starts on the straights. His springs should be fine for him. He rode with sth. like 98mm of sag, which is too little in my opinion and told him to increase it to 105mm. Because it's the only area he has problems with, I don't think it's an internal problem, just a matter of proper setup. I would rule out valving changes. I'm going to take the forls apart and rebuild them for him, anyway. What do you guys think?