Adjusting Vavles

[spyder0091]

i need help adjusting the valves on my 2001 400ex

[Doibugu2]

Look in either the FAQ section or the articles section. There is a how to on the site somewhere.

[Glamis400ex]

Buy a $20 manual...it's really easy

[guinness77]

I've done it with the help of my Clymer Manual. If you're mechanically inclined, it's easy. If you're not, find a buddy who is.
1. Turn the gas valve off. Make sure the ignition is OFF. Do not miss this step. No matter what... do not miss this step.
2. Remove the top plastic tank cover. Be gentle with the black plastic fender clips as you will need to re-use them. The tank cover isn't really all that impressive of a piece of plastic. But its gotta come off.
3. Loosten the front fender and gently pull it over the bumper. You do not have to remove it. It's held in place by a couple of bolts that are easy to find and several fender clips. Also, remove the rear seat/fender assembly.
4. Remove the black side panels. It's held in place by a couple of EZ to find bolts and fender clips. You will need allen wrenches for this step, and maybe WD-40 to loosten up the bolts.
5 On the sides of the gas tank are 2 rubber bungee-type straps. Slide them off.
6. Unbolt the gas tank. This is a bit of a challenge give the small area to work with under the handle bars. I hope you have an assortment of wrenches.
7. Carefully slide the hose that connects the gas tank to the carb off. It's under the tank below the tank on/off/reserve switch. There is a round clip that holds the hose to the gas tank.
8. The gas tank should be free now. Move it to a shaded, out of the way area.
9. Their is a white plastic heat shield between you and the cylindar head. That comes next. Remove the fender clips that hold it to the frame.
10. Their should be a black ventilation hose going into the shield from the carb. The heat shild simply acts as a brace for it. The hose should slide right out. Do not remove the hose from the carb. It's not necessary. (NOTE, this is NOT the long hose that travels the length of the shield
11. Wayyy up in front of the shield their is a hose that passes through it. The shield simply acts as a minor guide for that hose. Slide the hose out of the guide.
12. As you probably noticed, the tube that leads to the air box interferes with the shield removal. You'll have to really loosten-up that tube. to get to lift it up. You might have to remove it. But I've found simply loostening it up is plenty.
13. With careful sliping and sliding you can now slip the heat shield out from the side of the frame. You should not have to remove the long hose that travels the length of the shield. Just be gentle here. The cylinder head will now be visible.
14. Now lets move down low. On the left side of the motor case infront of (and above) the shifting lever their are 2 small access caps. Go ahead and remove them. You'll probably need to make a trip to the tool store to get the specialty parts. The large access cap allows to you view a big nut that you'll need to hook up to a socket. The smaller access hole allows you to view a timing wheel. ok, time to make you life easier. Get to the spark plug.
15. Get a length of clean rubber tubing. Insert one end into your mouth and blow all the sand and junk away from the sides of the spark plug. Don't use water, because you wont get it out and when the plug is removed you'll get water in the oil.
16. Loosten the spark plug 50%.
17. Now look at the cylinder head. Their are 4 large round access caps. Get a tooth brush and rag and really clean them off and the area around them too.
18. Gently remove the caps with the proper sized socket. No jury-rigging on this one. Do not strip the threads or socket mount.
19. ok.. lets go back down to access holes in the case. Put the socket onto the big nut and very gently turn the nut COUNTER clockwise. (You are turning the crankshaft here). If it doesn't want to turn, try putting the transmision into neutral. Continue to turn until you see the letter "T" appear. (First will come one line on the wheel, then shortly there after will appear a second line the the letter "T" beside it). Their is a cut into the small access hole that you can use to align the line with.
20. This step must not be missed. The piston must be TDC. That is Top Dead Center. ALSO the piston must by on the compression stroke. NOT THE EXHAUST STROKE. Check the valves by juggling the subrocker arms. (The subrocker arms enguage the valves. They are in plain sight in the valve access holes.) Check them by hand. If the arms are tight and will not move, then the piston is on the exhaust stroke. You'll have to rotate the wheel again. It is a 4 stroke motor ya' know. This might take a minute. [NOTE If all valves are closed except the right exhaust, you've got a jammed decompressor. This will give a clicking sound when the motor is running. You can release a jammed decompressor by moving the wrench/socket (that you currently have connected to the crank shaft) quickly back and fourth.]
21. Once everything is lined-up, Duck-tape the wrench that's connected to the crank shaft. You don't want it to move now that you spent all that time getting everything lined-up.
22. ok, now we get to check the valve clearance. (Whoopie!!!!) You'll need 2 different thicknesses of feeler guage. The exhaust valve clearance feeler guage needs thickness .12mm (.005in) and the intake valves need .10mm (.004in). Gently slide the correct guage between the valve and the rocker arm. When their is a little friction felt between the two, but the guage still slides fairly easily between the two, then congratulations. That's the right gap. But the odds are, you've gotta make an adjustment. To do this you need a wrench and a regular screwdriver. Their is a nut called a lock nut. It's on the rocker arm. It locks another part in-place. That part is the part that actually makes the physical contact with the valve. I call it the valve contact screw. It has a slot on the top so that a screwdriver can adjust it in...or out. But it WON'T move until you loosten the lock nut. Loosten the lock nut with your wrench making sure the screwdriver is holding the valve contact screw in place. That will keep the valve contact screw from turning while you're loostening up the lock nut. When the lock nut is loose you'll be able to tighten or loosten the valve contact screw. A turn of just 90 degrees is usually adequate. If the valve clearance was wayyyy loose, then you obviously want to tighten the screw down. Once you've turned the valve contact screw, re-tighten the lock nut. Make sure to keep the screwdriver in the slot because tightening and loostening the lock nut will mess up your perfect work. Recheck the clearance. You're an intelligent human being. Continue making adjustments until you're satisfied with all 4 valves.
23. Tourqe the lock nuts to 18 foot pounds.
24. Inspect those caps that allow access to the valves. They ought to have a rubber seal around them. If one is missing, you'll probably find it in-place in the head. Carefully remove it and put it on the cap. Torque the valve access caps to 11 foot pounds.
25. Re-tighten the spark plug. 1/4 turn for a used plug, 1/2 turn for new plug. (Note new plugs must be gaped to .6mm to .7mm (.024in to .028in)
26. Remove the wrench from the crankshaft and screw-in the caps. Turque to 10 foot pounds.
27. In reverse order, put everything back.
28. Turn on the gas.
29. Fire it up.

I make no gurantees. I've just done this so many times I have it down. Get a manual. It will save you a couple of thousand dollars in labor bills. ALSO...don't drink too much beer while doing this.