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I have an 05 Crf 250 that was hard to start. I see lots of people saying its the valves. i checked the valves and the clearances are:

EX

both .005

IN

right 0

left .005

I took the cam off but i wasn't at top dead center.

I put the new shims in and they are in spec but now i don't know how the cam goes. I line up the mark on the right side with the arrow and position the cam so the lines are level with the head , I also make sure the cam lobes are facing rearward. When i move the kick starter slowly with my hand THE CAM CHAIN AND CAM DOESN'T MOVE.It is like the 20 time i take the cam off and make sure the timing on the right is good and cam. Could the timing cause the cam and cam chain not to move. There is no dealer near me so I'm on my own. I am so frustrated! Please help and reply! Thank you

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Ok

Line up the timing marks on the crank, brake side of the motor. Then install the cam with the 3

2 small lines level with the top of the head. It takes some patience, you kinda have to roll the cam in and align it at the same time. Once its in you can't, or I can't move the chain. Have to get it right when it goes in. Take your time, don't over torque the cam caps.

You need a manual. And a torque wrench.

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Ok when I have it all lined up how do I know I'm not 1 tooth off or something? Also when I use the kickstrter to turn the motor is the lobe in the middle of the cam suppose to hit the exhaust rocker? I can't get past that with the kick starter or using the crank bolt. Do I just force the cam lobe against the rocker? I don't want to damage it thanks

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If you are one tooth off you will be able to see that.

The 2 alignment marks that are on the cam wheel will not be parallel to the head they will be slightly lopsided.

Make sure the timing marks on the crank / crankase are still aligned.

You dont need to move the kickstarter then, you are already at TDC, so its just a matter of being patient when installing the cam onto the chain.

Once its done, double check your cam wheel alignment and the timing marks on the crankcase.

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Is it ok if I can move the cam with my fingers when everything is tightend. I don't think that is normal and the marks are lined up and cam chain is tight.

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if your cam and chain isnt moving your chain is off the bottom sproket what you can do is lean the bike so its facing to the right slightly get some one to crank the engine over while keeping the chain taugnt it should get align with the sproket again. you will need to take the cam out again.

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My cam chain does move. I can move it left like 90 degrees. When I move it the crank on the bottom doesn't move. Is that normal. I am sure the cam is on right

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My cam chain does move. I can move it left like 90 degrees. When I move it the crank on the bottom doesn't move. Is that normal. I am sure the cam is on right

Sounds like Clint got it right the chain came off the bottom sprocket. Get the service manual and a good torque wrench. If you break the mounts off in the head or snap one of the bearing caps you will be buying a new head. Your method for aligning the timing marks sounds good. I pull the chain up taught on the non-tensioner side of the chain and lay it over the gear. That way you know all the slack is on the tensioner side of the chain. And make sure your tensioner is set so that it is in the loose position. That way you dont over tighten your chain.

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The manual says to remove the cylinder and I don't want to do that. Is there a way to see if the is not on the bottom sprocket by looking down were the chain goes. I don't think it came off the bottom sprocket because I can't pull it out but i can turn the cam with my hands when the cam caps are on. Could my chain be to loose or not on the chain guide?

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The manual says to remove the cylinder and I don't want to do that. Is there a way to see if the is not on the bottom sprocket by looking down were the chain goes. I don't think it came off the bottom sprocket because I can't pull it out but i can turn the cam with my hands when the cam caps are on. Could my chain be to loose or not on the chain guide?

You dont have to remove the cylinder at all.

Presumably there is no oil in the engine. If there is drain it.

Take off the ignition cover.

Remove the flywheel.

You can then see clearly if the chain is correctly seated on the crank, and if not its easy to put in place with the flywheel off.

Then put it all back togther.

I like to leave the FW off until the end.

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Can I see it with the flywheel on because I don't want to put it on wrong. When the chain is on right is are you suppose to be able to move it 360 by turning the crank? Because it always gets stuck on the exhaust rocker.

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it was the cam chain. it had fallen of at the bottom.

Edited by Trelex

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