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Hey guys. I recently purchased a 2008 Honda 400ex with some loud ticking from the top end. I figured doing a valve adjustment may help a little. I put it TDC and loosened the nut and screw on all four valves and the exhaust side will wiggle around but the intake is firm as can be and won’t move. Any ideas?
 

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Nope - I have no idea what the cause is - I suggest you take the head cover off to determine the cause of the problem
 

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Hey guys. I recently purchased a 2008 Honda 400ex with some loud ticking from the top end. I figured doing a valve adjustment may help a little. I put it TDC and loosened the nut and screw on all four valves and the exhaust side will wiggle around but the intake is firm as can be and won’t move. Any ideas?
Hi, I read this post and was confused. I got the message that the adjustment of the exhaust valve should be performed at the bump or the high part of the cam. I don’t believe that’s correct. I believe you want to adjust this valve off the bump when the valve is open. That represents normal operation.
 

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The valves are adjusted at room temperature (68 to 72 degrees F) with the piston near TDC of the compression stroke - the engine has to be rotated counterclockwise from the LH end - if the piston does not stop at TDC, it cannot be turned clockwise to get to TDC - doing so will activate the auto decompressor and affect the setting of the RH exhaust valve.

The engine does not have to be exactly at TDC as long as the rocker arm pads are on the base circle portion of the camshaft. You can stop a few degrees before TDC or a few degrees after TDC as long as the crankshaft does not turn clockwise from TDC due to the magnetic attraction of the rotor to the stator. So if it wants to rotate clockwise when stopping at TDC, go past TDC to the point the magnets stop turning the crankshaft CCW.

At this point, adjust all 4 valves to the prescribed clearance. Note: it is better to be loose a thousandths or two instead of tight a thousandths or two.
 
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