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Tech Tips Index > Kawasaki Prairie 650/700 BF650SRA Sign up or Logon

Prairie 650 700 - Valve adjustment

by North Carolina ATV Rider, 2005-02-28


Difficulty rating 7.5 out of 10 (the feeler gage was a bit hard to get in the tight spots).

-You need a feeler gage, flathead screwdriver, and a box end metric wrench (10mm). Check when engine is at room temperature (68F of so) otherwise the different expansion coefficients of the different types of metal involved will completely invalidate your valve adjustment.

1. Remove front plastic (includes top rack), middle plastic (includes battery), front inner covers, valve adjust caps, recoil starter. You might be able to do it without removing the front plastic if you take the left tire off. All the valves are easy to without taking the front plastic off except the exhaust valves on the front cylinder.

2. Remove timing inpection plug (black plug, left side of crankcase near recoil starter. It may be too tight for s big screwdriver. If it is too tight try a vise grip on the outside edge of it.

3. Turn crank counter-clockwise using a wrench on the crank bolt (under the recoil). Turn it counterclockwise until the TF mark shows up (the top part of the T lines up with a notch in the hole). Note that if the cylinder is at the end of the compression stroke all four valves will be closed (you can feel clearance in the rocker when the valves are closed). If the engine is at the end of the exhaust stroke, some of the valves will be partway open (the exhaust I think), and you need to turn it counterclockwise one full revolution until it is at the end of the compression stroke (back to same mark).

4. Check and if needed adjust all four valves on front cylinder to:

  • Intake 0.10-0.15mm (.0039"-.0059") cold
  • Exhaust 0.20-0.25mm (.0079"-.0098") cold

    * To adjust a valve, loosen locknut, turn center screw left for looser, right for tigher. Proper clearance is achieved when feeler gage can slide between valve and adjusting screw with slight resistance (not loose, not tight). I like to use a go-nogo gage made for motorcycles.

    5. Turn the crank counter-clockwise until the TR lines up in the timing hole and check/adjust the valves in rear cylinder. Make sure all valves are closed, because this it is 270 degrees CCW from TF. If some of the rear cylinder's valves are open (rocker is pushing them open), you may have turned the crank an extra 360 degrees after you adjusted the front valves or maybe you didn't do the front cylinder on TDC firing.

    6. Put stuff back together.

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