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03 250 New top end + some questions.

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Today I figured it was probably time to replace the top end, I had all the parts laying around so I went for it. I'm pretty happy getting 10 years out of a top end. Everything went smooth until I went to remove the cylinder, it seemed to be stuck, not sure why but I needed more room so I pulled the whole engine. After a half can of pb blaster and some gentle persuasion with a rubber mallet I finally got it off. Cleaned everything up and put it back together. Just waiting for clutch plates now and I'll put it back in the frame.

Old piston

1373339959104.jpg

Bike

1373339991963.jpg

I have a few questions though, 1)how would I go about polishing the engine? I've been scrubbing with some simple green for awhile to clean it. 1373338571649.jpg

2)Also what is a good technique to break the new top end in? I've heard 3 heat cycles, also heard just to keep it under half throttle for a 1/2 hour.

3) Do I need a new clutch basket? I couldn't get my camera to focus for the pic, but this is the best one. 1373338726088.jpg

4) what do I need to change in my carb? It seems to be running rich, I always get some black spooge out my silencer, I've never touched anything with the carb besides the air screw.

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Today I figured it was probably time to replace the top end, I had all the parts laying around so I went for it. I'm pretty happy getting 10 years out of a top end. Everything went smooth until I went to remove the cylinder, it seemed to be stuck, not sure why but I needed more room so I pulled the whole engine. After a half can of pb blaster and some gentle persuasion with a rubber mallet I finally got it off. Cleaned everything up and put it back together. Just waiting for clutch plates now and I'll put it back in the frame.

Old piston

1373339959104.jpg

Bike

1373339991963.jpg

I have a few questions though,

1)how would I go about polishing the engine? I've been scrubbing with some simple green for awhile to clean it. 1373338571649.jpg

2)Also what is a good technique to break the new top end in? I've heard 3 heat cycles, also heard just to keep it under half throttle for a 1/2 hour.

3) Do I need a new clutch basket? I couldn't get my camera to focus for the pic, but this is the best one. 1373338726088.jpg

4) what do I need to change in my carb? It seems to be running rich, I always get some black spooge out my silencer, I've never touched anything with the carb besides the air screw.

1, elbo grease, stool wool, scotch brite paint scuffing pads, mothers polish. etc. takes a while

2. 100 different ways. the point of a break in is to seat the rings in the cylinder so they wear together. I just ride my bike with a new top end. just not wide open for half a tank or so. key is to keep the engine under a load. not wide open but under a load.

3. yes that one is toaaaaast

4 find out what jetting you have. but this is what you need. read this 45 times. take a break and read it a few more times. its all you need to know. I ended up around a 380 main and stock pilot on my 02. but all bikes, riders and weather conditions are different.

http://www.kawasakimotorcycle.org/forum/kawasaki-motocross-offroad/17227-spankeys-jetting-guide-info-2-stroke-riders-must-have.html

here the 02 i had back when, good bikes. need a bit of work toget the most out of them but still great bike

4saleagain003.jpg

repack the silencer as well.

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1, elbo grease, stool wool, scotch brite paint scuffing pads, mothers polish. etc. takes a while

2. 100 different ways. the point of a break in is to seat the rings in the cylinder so they wear together. I just ride my bike with a new top end. just not wide open for half a tank or so. key is to keep the engine under a load. not wide open but under a load.

3. yes that one is toaaaaast

4 find out what jetting you have. but this is what you need. read this 45 times. take a break and read it a few more times. its all you need to know. I ended up around a 380 main and stock pilot on my 02. but all bikes, riders and weather conditions are different.

http://www.kawasakimotorcycle.org/forum/kawasaki-motocross-offroad/17227-spankeys-jetting-guide-info-2-stroke-riders-must-have.html

here the 02 i had back when, good bikes. need a bit of work toget the most out of them but still great bike

4saleagain003.jpg

repack the silencer as well.

Thanks for the reply. What's the easiest way to repack a OEM silencer? I believe it's riveted together.

Thanks for the jetting link, once I get the bike broken in I'll have to attempt to fix my jetting.

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