Two Stroke Motocross
Two Stroke Motocross Forum => Technical => Topic started by: Shadow on July 18, 2011, 10:35:45 AM
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Alright, somebody help a dumbass out.
'02 kx250. Service manual "helpfully" instructs to turn cylinder upside down and to remove exhaust valves. Now, if anyone could tell me just how do I go about doing this? It seems to be the most simplest of things as no one has bothered to explain it anywhere, but I tried to just pull those things out and they don't move with any reasonable use of force, and I'm not going to risk breaking them before I get more info.
(http://img695.imageshack.us/img695/1899/16072011328.jpg)
Those three thingies. How the hell do I remove them so I can clean that power valve properly?
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Isnt there an allen key bolt either side at the bottom which hold em in? I thought they come out from the top if you push them with the cylinder upside down? Maybe im thinkin of another type. Its been over ten years since i played with kx. Dont stress someone here will have the answer.
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Nope, no allen bolt, the way it's laid out and looking at the explosion picture, they should just come out by pulling them but those are either stuck or so tight that I'm going to break something trying to remove them if I don't get some helpful advice from more experienced guys.
Note that the KIPS hasn't been serviced even once in the past three years thanks to the previous owner's negligence. Which is why I want to disassemble the kips completely.
I don't know if this helps you understand how it is. It's from an 03-05 kx250 service manual but the instructions in my '02 service manual are identical for this section.
(http://htmlimg2.scribdassets.com/194oztf5j4vtgtq/images/122-53c440caa0.jpg)
1st pic
Exhaust Valve Removal (KX250 Model)
â?¢ Remove:Carburetor (see Fuel System chapter)Cylinder Head (see Cylinder Head Removal)
â?¢ Remove the KIPS cover at the cylinder
â?¢ Remove the E-clip [A] and operating rod collar fromthe operating rod.
â?¢ Remove the cylinder (see Cylinder Removal).
2nd pic
â?¢ Turn the cylinder up side down.
â?¢ Remove the plug [A] and the gasket at the left side of the cylinder.
3rd pic
â?¢ Pull out the operating rod [A] as far as it goes.
â?¢ Remove the operating rod retaining screw .
4th pic
â?¢ Remove the idle gear [A].
â?¢ Lift up the exhaust valves , and remove the valveguides [C].
â?¢ Lift up the exhaust valves, and pull out the operating rod[D]. Then take out the exhaust valves.
5th pic
â?¢Remove the main valve cover [A], main valve rod cover and cylinder left cover [C] from the cylinder.
(http://htmlimg4.scribdassets.com/194oztf5j4vtgtq/images/135-2a2b2a5ad6.jpg)
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Those drums should just pull out when you pull the rod out (that will stop and not come all the way out). To remove the rod you have to have those top valves out first. They just drop in, so it sounds like they have been in there a long time without cleaning. I would suggest trying to soak them in oven cleaner or PB blaster for a day and see if they loosen up.
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That's the info I was needing.
Thank you good sir.
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I had trouble with this on my 2005 KX250. Coming from a four stroke background it was weird to me. The best thing for me was the color photos in the cyclepedia.com (http://cyclepedia.com) manual. I have one for both my 250s the four stroke and the two stroke. Now that I got the exhaust valve cleaned up my two stroke is definitely faster than the four!
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I had trouble with this on my 2005 KX250. Coming from a four stroke background it was weird to me. The best thing for me was the color photos in the cyclepedia.com (http://cyclepedia.com) manual. I have one for both my 250s the four stroke and the two stroke. Now that I got the exhaust valve cleaned up my two stroke is definitely faster than the four!
I did my top end not to long ago and had a tough time really cleanning up the valves and i was curious on what you used to clean them up?