Yamaha Raptor valves adjustment
Tools you need:
Breaker Bar (optional)
3" Extension (not shown)
4MM Hex Key
5MM Hex Key
Yamaha Spark plug socket (not shown)
Philip Screw Driver (or socket like on the picture)
Service Manual for Torque Specs and Valves Clearance
Optional: Canadian 2$
AND A STONE COLD ENGINE!!!!! best way to do it is if the engine hasn't run overnight!
First you need to remove the front plastic.
Use the 10MM socket to remove the bolts (displayed with red arrows).
Use the 10MM socket and philip screw driver to remove the screw and nut (blue arrow)
Remove the hood with the 4MM HEX key (yellow arrow)
Once the hood is removed, remove the last 10MM bolt that holds the front plastic (red arrow)
Now remove the plastic tank cover (cannot remove the front plastic with it in place). It's holding with plastic clips, only ~1/2 turn with a screw driver
will allow you to remove them. (red arrow)
You might want to clean the plastic cover before you remove it as you have to remove the gas cap to take it off. You don't want any dirt in your gas
OK now you're ready to remove the front plastic.
it can be a little tricky when it's the first time you take them off.
You have to pry a little on those tabs to lift the plastic as they're holding by that little bump where you removed the bolts.
Now that the front plastic is free to move, lift it ~4-5" but be careful! the reverse knob might hold it a little. You dont want to break it ;)
Now pry the back of the plastic so both sides will go arround the wire and cables on each side of the steering (pink arrows) and pull it toward you.
Now with the plastic off
Now you have to remove the 2 remaining 10MM bolts on the gas tank (red arrow)
Turn off the petcock (green arrow) and remove the gas line (blue arrow)
Now put the gas tank where the petcock will not touch anything, a milk crate if perfect for this task!
Now you have access to a rubber hood that covers the intake valve tappet cover. You have to remove it by "fighting" those 2 reusable tiewraps (green arrow).
Since you'll take to turn over the engine manually, remove the spark plug with the yamaha spark plug socket. You'll need your ratchet and the 17MM socket.
Again you might want to wipe off the dirt before you remove the spark plug cap.
*no pics of this step*
Once the plug is removed you need to take off the covers for the timing and crank bolt (red arrow). A Candian 2$ will fit perfectly and will not damage your
covers (a 1$ wont fit, it's too tick). If you're not Canadian or do not have a 2$, you may try a big screw driver but be careful as those covers are in
Those are the 2 covers. Watch those little O-rings!!! They might stick on the engine and fall off. You're better to remove them and keep them on the covers.
Clean them up too! (green arrows)
This is what you'll see once the covers are off.
I always wipe off the oil in the thread with a rag or scott towel and then use it to remove the dirt around the hole (green arrow). The dirt will stick in
the oil and wont enter the engine.
Now take the ratchet (or breaker bar), 3" extension and 19MM socket (3/4 will work too but it`s a little too big) and turn the engine COUNTER CLOCKWISE
(yellow arrow). Align the I mark with the grove (red arrow)
Once they're alligned, take off the intake valves tappet cover, you might want to clean it before with a rag as you dont want any dirt in your engine!!! It's
holding with 4 5MM hex screws (blue arrow)
Clean up the mating surface of the cover and the O-ring (green arrow)
Now you have access to the intake valves (red arrow) and clean the surface on the engine (green arrow). Be careful with the cleaning!!! Again you dont want
any dirt in your engine!
Now to find out if you're at TOP DEAD CENTER (or TDC) I alway use a smaller feeler, if it's not going in, your most likely crank turn off (which means you're
not at TDC).
As stated in the service manual, if there's no clearance, you're not there yet (need to do another turn).
See the picture, the .076 isn't going (I use the .076MM feeler because I know my valves wont out of spec that bad).
I did another counter clock wise turn and now it's freely going in!
Now the clearence specs for the stock cam are .100MM to .150MM .
I always use the feeler the closest to the average which is .125MM (with my feeler the closest is .127MM)
It have to be a snug fit! not too loose and not too tight.
If the valves are within specs the .100MM feeler will go in freely and the .150MM will not fit in!!!
If the .100MM is tight or .150MM is loose it's time to adjust the valves.
The way I do it is, I loosen up the lock nut with the 10MM key (red arrow), take the needle plier and turn ~1/2 the adjuster with the needler plier (yellow
arrow). Fit in the .127MM feeler, tight the adjuster back a little and retight the lock nut! Do it for the 3 intake valves.
Once it's done I do 4 or 6 COUNTER CLOCKWISE turns on the engine with the ratchet (or breaker bar).
Recheck the valves! If within Specs, put back the tappet cover! YOU'RE DONE for the INTAKE!
Now it's time for the exhaust valves! They're a little tricky to do because the space is LIMITED!!!
Take off the 2 exhaust valves tappet covers with the 17MM socket (yellow arrow).
See there's not much space to play around
See where you have to squeez in the feeler
To do the exhaust it's easier with a bent feeler, I bent mine with a custom angle where it fits quite easily.
As I do with the exhaust I go with an average to adjust the valves.
Specs with the stock cam are .150MM to .200MM. Myself I go with the closest I have which is .176MM.
To insert the feeler easily, I slide from left to right!
Again for the specs If the .200MM doesn't fit and the .150MM is loose, you OK. If the .200MM fits, even snug, I'll retight them a little.
If the .150MM is snug, I'll try to loose them up to .176MM. Do that for both exhaust valves.
Once adjusted, I'll turn again the engine 4 or 6 turns COUNTER CLOCKWISE and recheck. If they're not within specs, do it again!.
If they're within specs. Put back the tappet covers, YOU'RE DONE!!!!