How To: Adjust Your Valves (700 or 660)

[Krandall]

Although I give a warning. This no lies. Is probably one of the easiest things that you can do. It seems scary going into the motor and all, but... So easy a caveman could do it! 


****Warning****
Your doing this at your own risk.  I am not a certified Yamaha mechanic and only expressing my thoughts and veiws on adjusting valves.  If for any reason you don't feel comfortable doing this, take it to your Yamaha certifed mechanic.


1.  Make sure your machine is clean prior to starting this task.  It's very easy to get dirt, grime and mud into the valleys where the valves are.  It's never fun to work on something dirty and I suggest giving her a bath prior to starting anything below.  Also be sure you have a clean working area for those bolts that fall out or could roll away.

2.  Please folks remember your working with gas and removing fuel lines with vapor.  It only takes a spark and boom your machine is in flames.  Also keep good ventilation going to help keep your mind clear and your body healthy.

3.  Start by removing the seat by pushing against the plastic latch until you pop the seat up.

4.   Remove the positive battery cable prior to anything to help prevent sparks which is located under the black rubber cover under the seat.  This will require a large phillips head screwdriver.

5. . Remove the front radaitor cover which is secured by the 2 allen screws directly under the handle bars.  Once the 2 bolts are out, slide the cover towards the rear of the machine which will allow the "feet" to come out of the grove.

6.  Next on the list is removing the tank cover which is only held on by plastic inserts and the gas cap.

7.  Next let's remove the front fenders by removing the bolts and plastic inserts that bolt everything down.  This will consist of 2 allens with 10mm nuts and 3 other 10mm head bolts "2 under fender" and one directly in the front of the radaitor.  Lastly there are 2 more that secure the front and rear fenders near the battery tray.

8.  There is a vent tube "clear" that you must remove near the bars and then unplug the display unit's feed "witch" to allow removal of the complete front section.

9.  Gas tank removal requires you take the 4 10mm bolts out and removal of the fuel pump power connector and the fuel line itself.  When removing this remove the black retainer plastic which will allow you acces to the orange clip.  Take your time and slowly pull back the arms which will allow it to slide away from the line and gain you the space needed to pull the line off.  I would strongly suggest you get a zip loc bag and place it into there to help prevent spillage of fuel.  Lastly remove the 2 plastic inserts near the rubber and then remove the tank.

10.  Next and the hardest is the heat shiled for the tank.  There are groves cut in the front that hold the wires near the stem.  Remove these and the vent tube in the bottom.  Take your time as this part is difficult to remove wihtout damaging it.  Once you get the lines free pull it to the rear to remove it.



                                                           Now for the easy stuff !!!  VALVE adjustments!!

11.  Please clean all around the covers....dirt will always find it's way into these areas!!!!!!

12.  Remove the Timing Mark accessory screw with the allen tool

13.  Remove the Crankshaft end cover which will allow you to turn the engine over.  This will require a 14mm allen or you can also use the other end of your spark plug tool.

14.  Remove the spark plug with the tool kit you have in the rear.

15.  There are 3 covers that need to removed.  They are held by 8mm head bolts.  These are on the top near the FI,  another near the exhaust pipes and then the one where your timing chain is located.

16.  Now since the Raptor is a 4 stoke "Intake- Compression-Power-Exhaust" we need to get the engine to TDC or top dead center on the compression stroke.  This is easily done by using the 22mm deep well socket and rotate the engine Counter Clockwise until 2 things happen.  First you need to align up the mark on the flywheel with the mark on the case.  There are 2 marks... the "H" which is used for timing and then a plain  "I" mark which is used to identify TDC.  You will know your on the right stroke because near the timing chain you will see the line on the cam gear and the case also match up.  there should be very little resistance once your there and the plug is out.  Wiggle the rockers and they should be semi lose.  If you have  (0) clearance your not on the correct stroke.

16. Now get your taper feeler gauges out which should be in MM to measure these engines.  Start with the intake and measure each one.  If correct, there should be .09 mm- .13mm.  When you measure there should be a slight resistance when sliding it through.  If it's tight then you know you need to losen the nut and turn the tappet adjuster counter clockwise to losen it slightly or vise versa.  Once you can slip in the feeler gauges and feel just a slight resistance, hold the tool still and tighten up the nut and recheck it one more time.  Next goto the other valve and follow the same procedures again without turning the engine over.  Adjust this one accordingly.

17.  After adjusting the intake side I would roate the engine a few times Counter Clockwise and recheck these once you've found TDC again to ensure you have it perfect.

18.  Next move onto the exhaust and follow the same procedures except this time you want clearances to be .16mm - .20mm so you will need to swtich out your gauges for the next size up.  The small taper set you can order really help out here when trying to do your valves.  Once you've done both here rotate the engine over a few times and locate TDC and recheck all of these. 

19.  Once your certain you've got them correct, spin the engine about 20 times and then locate TDC once again and check them all once again as a tripple check....then button her up.

20.  Reinstall in the reverse order and I would suggest an oil / filter change to top off the job after your start it and warm it up to flush any possible contamination away into the filter.



                                                                                   ***NOTES***

1.  Make sure duing all this process you don't drop anything into the engine.  Commen things include bolts for covers, O ring for covers, allen tools or sockets.  I would use a rag and cover everything when your not directly in that spot.  I do suggest you pick up an expandable magnet to help retrieve anything that could fall just in case.

2.  Let me explain some theory here on valve adjusting....like how tight should I put in on that scale etc.

When adjusting valves the whole reason your doing this is to keep clearance in acceptable ranges. If you get to tight, the valves never close completly and can burn valves or lead to the valves hitting the piston.  If you get them to lose then you will create slop which leads to less HP because your valves are not opening as much which will limit the air traveling through.  There are 2 parts to a cam that are important.  You have Duration and you have Lift.  The duration is "at the highest point of opening" the total time the valve remains there allowing air in.  The lift "total valve height opening" which allows the air to flow through creating HP. 

Now the reason you purchase after market cams is for both increase lift and duration to bump HP.  The reason you need after market springs is to compensate for the increased lift and prevent floating of the valves when using more radical cams that have a different ramp leading to the peak point.  If you adjust your stock cam on the tight side it will provide more lift increasing HP but will require more attention sooner.  The main thing you DON'T want to do is create to little gap and create PSI losses which burns valves becausing your looking for that little extra lift.  Hence the reason you have the minimum specs.  I would always adjust them for the lighter side because, as valve and seat wear happens the valves move closer to the tappet requiring more adjustment. 


There's not much to this style of adjusting other then taking the time to do this properly.  Keep everything clean and always put bolts back into the holes so your not playing the guessing game during reassembly.  Listed below are the tools needed for the job.  The complete thing takes about 3-4 hours and is very easy guys/gals.

1.  3/8 Drive Ratchet
2.  3/8 Drive Torque wrench that measures in  "IN-LBS"
3.  3/8 Swivel
4.  3/8 Drive  8mm, 10mm and 22mm (Deep well for 22mm)  sockets
5.  3/8 Drive 6" extension
6.  3/8 Drive 4mm, 6mm and 14mm Allen sockets
7.  8mm, 10mm, 14mm combination wrenchs
8.  Stock Spark plug tool
9.  Small Standard screwdriver and Large Phillips screwdriver
10.  Taper set of "MM" feeler gagues...."Dealership"
11.  Tappet adjusting tool "Dealership"
12.  Expandable Magnet
13.  Set of "CROWS FEET"  "to tighten the adjusting nut on valves"


                                                                                     ***TORQUE SPECS***

1.  Locknut for valves------------------------------------------- 10 FT LBS  or 120 IN lbs
2.  Timing Mark Acc Screw--------------------------------------- 4.3 LBS     or 51 IN lbs
3.  Crankshaft End cover------------------------------------------7.2 LBS    or 86 IN lbs
4.  Spark Plug ----------------------------------------------------9.4 LBS    or 113 IN lbs
5.  Camshaft Sprocket cover--------------------------------------7.2 LBS     or 86 IN lbs
6.  Valve covers both intake and exhaust--------------------------7.2 LBS     or 86 IN lbs

taken from here: http://www.raptorsource.com/forum/index.php?topic=28.0

[speeddrive1]

If you don't mind, I would like to add something to your already excellent write up.
1. Make sure the motor is cold when adjusting the valves, let it set overnight and then adjust them.
2. If the timing mark cover and crank bolt cover are hard to remove you can heat them up with a propane torch.
Just don't heat them up untill the paint is bubbling, just warm them and they will come out alot easier.

[Krandall]

excellent thanks!! Also.. if you need cam specs they are located here:  http://www.raptorsource.com/forum/index.php?topic=2020.0

[Flynbyu]

Great writeup!

~Brian