How To: KX240F Valve adjustment

[elskipador]

as much as i love/d my 98' kawi KX125 2-stroke it and the rest of its brothers are on there way out. since about 96 or so all the factories have been working on making a high-performance 4-stroke. @ 1st i was against it. i really love 2-strokes! however the new 4's are really good. they've become very fast and lite. and not to bad, from a service view. they don't need the top-end replaced a lot, but they are way more needy than their tappet-valve brothers. the manual says to check the valves every six races, i'm not sure but i'm guessing that would be around 4~6 hours of riding time.

start by removing the plastics and seat.

 

[elskipador]

then the radiator shrouds. all of the plastic's bolts have a 8mm head

 

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remove the front tank bolt

 

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and rear strap

 

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turn the gas off and disconnect the fuel line

 

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disconnect the coil and cap. remove the 2 allen bolts holding the valve cover on.

 

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remove the spark plug

 

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remove the timing inspection & flywheel plugs

 

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remove the valve cover

 

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set the motor to TDC of the compression stroke. the cam lobes will be facing opposites direction. the flywheels mark (right 1) lines up with the notch in the case cover

 

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the marks on the cams line up with the top of the head, and both cams have a second mark that points up. i've marked them with white dots, my camera can't focus close enough to get good detail

 

[elskipador]

measure the amount of clearance between the cam and valve bucket. the intakes should be 0.10~0.15mm and the exhausts should be 0.17~0.22mm

 

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if the clearances aren't within spec the cams will have to be removed. loosen and remove the CCT bolt and spring.

 

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take out the 2 bolts holding the CCT in place. slide to back, so that there is no tension on the cam chain

 

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remove the 4 bolts holding the cam caps in place. there will be 2 dowel pins and a half-moon clip, do not let any of these fall into the motor!!!

 

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the cap and clip removed, these dowels stayed seated in the head

 

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remove the intake cam

 

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measure the shims and replace it with the size that gives the correct clearance

 

[elskipador]

after all the needed shims changes are complete for the intake put the cam back into postion and bolt it back down. torque the cam cap bolts to 12 N/m and do the same procedure for the exhaust valves. when thats done recheck all clearances!!! to make sure they're correct. after that bolt it all back together and go for a ride

 

[elskipador]

damn i just notice that i titled this KX240F...theres no 240, the bikes a 250. so much for proof reading