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Walkthrough on changing top end?

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I've tried doing some searches on the forum for a walkthrough for changing the top end on a 03 kx250. Does anyone have a step-by-step guide for doing this? I've never changed this before and this kx is also my first 2 stroke. I don't need to change my top just yet but I like to do my research before just opening things up!

I found a step-by-step guide for the 4-stroke valve job and was able to shim my valves on my kxf250.

I do not drop anything off to a shop if I do not have to.

thanks in advance

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its really common sense. just remove the radiators, plastics, carb and pipe. also pull the shaft for the power valve and then unblolt the "top end" and then install the piston, actually way more simple than it sounds. i missed a few steps however its really self explainitory for someone with basic mechanical skills

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it's pretty easy, you can figure it out as far as getting down to taking the cylinder off if you use common sense. just a couple tips: when you get down to the powervalve, and the internal parts of the powervalve if you are going to clean them, be careful to not overtighten the bolts, they will snap easy. get a couple of paper towels and put it under the piston so nothing falls down into the crankcase. make sure you clean off all the old gasket material before you re-install. de-glaze your cylinder by getting an aluminum oxide hone 240grit to hone the cylinder, you dont have to worry about harming a chrome plated cylinder with one of these hones either, the aluminum oxide won't harm it if you don't use it excessively, just do a couple passes.

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You may have to use a diamond hone depending on your bike. I know for the electrofusion coating on my KX250 cylinder, the manual recommends a diamond type hone.

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