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HELP! cant figure out whats goin on kx250f

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i just replaced my head gasket in my 06 kx250f and i put it all back together and when i go to kick it over my kickstart gets hung up it feels like, and wont go down. i think it might have something to do with my timing chain but im not sure...i was pretty sure i had my timing chain on perfect ! please any suggestions will help i havent been able to ride in 2 weeks !!

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Go back and double check timing. Ask a friend to look at it too.

Is the auto decomp moving freely?

The second (right) mark on the flywheel is TDC. And the cam lobes should point up and away from each other.

Carefully check that the dots on cam sprockets is level with head.

Also make sure that rubber stopper in head cover hasn´t fallen down into timing chain lower sprocket.

Check that cam sprocket hasn´t moved on the shaft. The hole in the sprocket should visually line up with hole in outer cam lobe.

Does the engine turn over easy with 14mm socket on flywheel nut? Remember it should be turned to left (CCW).

How far out was the chain tensioner? As in how many clicks?

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Sounds like the chain tensioner to me. I believe on that one there is a little thing you push on the top of it to push it all the way back in. Then you put the lil rod and spring in it and install it on the bike. If you didn't reset that tensioner it is probably pushing on your timing chain really hard and making it drag and hang up... I've done the same thing before. Break the 12mm bolt in the middle loose first, then loosen the two 8mm bolts.

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I just rebuilt my top end do to a bad head gaskit. I think maybe when you slid the piston back into the head It could have binded a little. I used lots of oil and maid sure the piston moved up and down before i put it on the bike. My second guess wold be your cam chain not tight and fell of cams or somthing fell in the moter during rebuild. Try removing big screw on left side put a socket in and try to turn moter over slow you can get a better look at whats going on with the top valve cover off.:)

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Dude, when you put a new piston and rings in the last thing you want to do is put a whole bunch of oil on it. Just a few drops on the bottom of the piston skirt is all you are supposed to do..... You want the rings to seet into the cylinder, and if it is all covered in oil it doesn't do to well.

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Dude, when you put a new piston and rings in the last thing you want to do is put a whole bunch of oil on it. Just a few drops on the bottom of the piston skirt is all you are supposed to do..... You want the rings to seet into the cylinder, and if it is all covered in oil it doesn't do to well.

Not True. You want to oil the cylinder walls and the rings good so you don't have issues right at start-up. It'll burn the oil up in a very short time.

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I can tell you that team suzuki does it my way. So true. It might work your way but I guarantee the rings will seet better into the cylinder wall my way. Ask a profesional mechanic his opinion. Sprint car engine builders do the same thing.

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Dude, when you put a new piston and rings in the last thing you want to do is put a whole bunch of oil on it. Just a few drops on the bottom of the piston skirt is all you are supposed to do..... You want the rings to seet into the cylinder, and if it is all covered in oil it doesn't do to well.

HAHA Why waste any oil, just put it together dry, and NEVER clean your new piston/cylender it is highly over-rated.:)

anyways def. check your cam chain tensioner, hope you figure it out:thumbsup:

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Not True. You want to oil the cylinder walls and the rings good so you don't have issues right at start-up. It'll burn the oil up in a very short time.

I agree, thats def. the proper way!:) You can also use red-line assm. lube, the excess oil/lube will burn off very fast, its just cheap security, and rings don't seat in 2 minutes

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which way does the chain tensioner go back in ?

The tensioner is mounted after the cam caps are tightened. Cam caps should be torqued to 10 Nm.

The tensioner should be taken apart. This should be done when disassembling.

You reset it by pushing with finger on the small "ratchet" mechanism that holds it from backing out, then push it back.

The spring and rod and cap goes on last.

Mount the tensioner with the ratchet facing up. Tighten the two small screws. Then put in spring and the rod that goes inside the spring. Then put aluminum cap over and push in and thread it in. You will hear the tensioner clicking out when you put pressure on the spring with the cap nut.

This way only the spring puts force on the chain. If not mounted properly it can overstretch the chain and lead to a failure.

Another thing, if the black plastic chain guides were taken out, make sure they are properly in their seats.

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I can tell you that team suzuki does it my way. So true. It might work your way but I guarantee the rings will seet better into the cylinder wall my way. Ask a profesional mechanic his opinion. Sprint car engine builders do the same thing.

Dont mean to be a smart ace and hate to burst your bubble, but i build high performance circle track engines for a living. During assembly your rings should be oiled well as well as the cylinder walls in a nice thin film of oil, as well as a good priming of the oil pump before start up. Like previously stated, upon start-up, the excess oil on the rings and cylinder walls will be quickly burnt up. If properly broken in your rings will seat just fine. :)

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I agree, thats def. the proper way!:) You can also use red-line assm. lube, the excess oil/lube will burn off very fast, its just cheap security, and rings don't seat in 2 minutes

I have an Aircraft Mechanics license and this is what most in the aircraft industry uses for assembly lube. They mix whatever normal engine oil the aircraft uses 50/50 with STP oil treatment. The STP is very sticky and makes the oil stick well to the parts so the oil doesn't just run off and into the pan. I also use special cam lube on the cam's during assembly. When I assemble an engine I do it to make it last. Team Suzuki might put it together very dry. Well the rest of us aren't Team Suzuki. Team Suzuki builds their motors so that the rings seat immediately. They don't care about longevity. Their engines only have to make it 40 minutes. When Ryan Dungey blew up his bike at A1, they had to throw another motor in it pronto. They didn't have time for him to go out and break it in. It had to have the rings seat within minutes. But it also only had to survive one moto. I need my engines to last a heck of alot longer than that. The rings will have no problem seating within a reasonable amount of time.

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It´s interesting to know how race teams do it. But it is not the way for mortal men on somewhat of a budget.

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