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Difficulty taking apart top end


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Hey guys,

So my manual is kind of confusing on how I should be marking this as I take it apart. It says in the manual to move the nut at the bottom (in picture) but I'm not sure if that's what it means. Can anyone make this more clear for me?

I also have no idea if anything in here is seized, but the crank sure is because my kick wont budge. How do I properly remove this without screwing up my timings?

Thanks!

... apparently I'm not allowed to post images, so here are the links..

http://imgur.com/lSf2S

http://imgur.com/S1L6J

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remove center bolt from cam chain tensioner (under intake port). then wind it up with a flat blade screwdriver to loosen it. the chain should be loose enough now, if not remover the whole tensioner. pop the chain off then remove cams etc. when putting it back together make sure the timing marks line up on the flywheel and cams. i hope that made sense lol

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I think it's saying to use a socket to rotate the nut until the timing marks line up... I'm not sure why. If the piston is seized you won't be able to do this. Will the nut rotate? Don't force it or you'll just unscrew the nut, it should be fairly easy to do.

If you're trying to remove the head, then do what Motofreak said.

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I think it's saying to use a socket to rotate the nut until the timing marks line up... I'm not sure why. If the piston is seized you won't be able to do this. Will the nut rotate? Don't force it or you'll just unscrew the nut, it should be fairly easy to do.

If you're trying to remove the head, then do what Motofreak said.

My thoughts exactly... I tried to rotate the nut (the yamaha manual says to rotate it CCW, so... loosen it.) and the nut just broke free and started to loosen right off (which makes sense), but I have no idea how it's supposed to rotate the piston or anything.

remove center bolt from cam chain tensioner (under intake port). then wind it up with a flat blade screwdriver to loosen it. the chain should be loose enough now, if not remover the whole tensioner. pop the chain off then remove cams etc. when putting it back together make sure the timing marks line up on the flywheel and cams. i hope that made sense lol

It makes sense. I'm not gonna lie, I'm no uber engine mechanic or anything. I can identify many of the parts, but I don't know what the flywheel looks like. I think it's the part at the bottom where the nut is that I've removed (I'll just assume it's a sprocket).

So when putting it back together, I know where the markings are on the flywheel (assuming I've identified it correctly), my manual says something about lining up a letter in the site hole above the flywheel hole, and at this stage the piston should be at the very top or something (the manual isn't in front of me at the moment ?).

That being said, I don't recall there being any markings on the cam shafts. Also wont I have to mark the valves somehow too? Or I guess those are positioned by the cam shafts themselves, right?

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The nut you removed holds tge flywheel ( big steel cup with magnets) onto the crankshaft. Normally, rotating the nut rotates the crankshaft and makes the piston go up and down.

Rotating the flywheel so the marking lines up with the small window will place the puston at TDC (top dead center, or the top of it's stroke) where it needs to be to check valve clearence (compression stroke) and as a reference for setting cam timing.

The valves will have dots on the side of their sprokets. These dots should be aligned per the manual with the piston at TDC and that will insure the valves are timed correctly.

If you are re-using the valves (I personally wouldn't after problems but it is a lot to replace them ) they should be replaced in their same spots. You don't need to worry about timing them, they are opened and closed by the cams.

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