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Discussion Starter #1
I was just reading the cylmer manual on servicing the valves but it just ended up confusing me. Im assuming since it states to open up the engine cover that I should drain the oil first before going through that step. Why would it not mention that? I also heard that you can put the bike in sixth gear and rotate until the pressure of the valves are released in order to skip the opening of the engine cover, is that an easier way or should i just stick to what the manual states?
 

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Do you mean,open the alternator cover to find the tdc mark? Just pull a spark plug and stick a screwdriver in the hole, roll the engine ahead until the screwdriver is at the highest spot. That will be top dead center, where you can adjust the valves.
 

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Discussion Starter #3
Do you mean,open the alternator cover to find the tdc mark? Just pull a spark plug and stick a screwdriver in the hole, roll the engine ahead until the screwdriver is at the highest spot. That will be top dead center, where you can adjust the valves.
The manual just said engine cover but I think your right its the alternator cover.
 

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Discussion Starter #4
I was adjusting the valves since I heard a slight ticking noise when the engine was running. The valves are adjusted and the cam chain was also adjusted for good measure but it seems that i still have the ticking noise and I can't figure it out. I was hoping it was the valves but if they are in good working order what else can it be?
 

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There is no oil inside alternator cover on 3 valve Honda's.
On earlier 450's, lean bike to right with a 1" piece of wood under left centre stand leg.
Unless your doing a full service you don't need to drain oil (although it's normal to do oil as part of full service and adjust valves while your waiting for complete drain - takes longer with cold oil and you need engine 'room temperature' to do valves)
If you have ticking, you probably did valves on overlap instead of compression, ot, it may be balance shaft chain?
 

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Discussion Starter #6
I loosened the cam chain tensioner nut about 3/4 turn and I didn't really hear a difference. I will double check the valve adjustment I did but I keep getting the same ticking noise. Do I have to replace the cam chain tensioner or the valves. It seems like its coming from the right side.
 

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A certain amount of noise from the valves is normal.
 

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There are two, 12mm for adjuster and 14mm holding quadrant onto splined shaft.
You didn't adjust valves on overlap did you? (In my experience, way more common than people imagine)
 

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It has a 360° crankshaft, that means when a camshaft lobe is at maximum lift the lobe on the opposite cylinder lobe will be on the base circle. With the adjustment covers removed, turn the engine over until you see the left side intake rocker go all the way down(intake open). Now adjust the right side intake valve. Turn the engine over until the right side rocker is all the way down and adjust the left side intake valve. Repeat those steps on the exhaust side of the engine, all done no need to remove the alternator cover, no need to obsess about getting things EXACTLY on tdc (as some folks are wont to do).
 

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Discussion Starter #11
There are two, 12mm for adjuster and 14mm holding quadrant onto splined shaft.
You didn't adjust valves on overlap did you? (In my experience, way more common than people imagine)
How would I check that im on overlap? Place something in the spark plug hole and feel for compression?
 

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Both vales will be partially open on the overlap stroke. If the rockers are tight go around one turn and check for movement.
 

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I was just reading the cylmer manual on servicing the valves but it just ended up confusing me. Im assuming since it states to open up the engine cover that I should drain the oil first before going through that step. Why would it not mention that? I also heard that you can put the bike in sixth gear and rotate until the pressure of the valves are released in order to skip the opening of the engine cover, is that an easier way or should i just stick to what the manual states?
Remove the spark plugs, use top gear to turn engine in forward direction, watch in spark plug hole for piston to be at TDC, and valve action, perform adjust on side at compression stroke TDC, other side will be at valve overlap, (exhaust closing, intake opening), Then rotate 1 turn and adjust other side. No need to remove left engine cover, ( it's a "DRY" case, no oil) watch for TDC thru spark plug hole. HondaJohn
 

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Because you have to remove the complete valve/rocker cover it's easy to look at cam and see if the rocker arm is on base circle. You can watch the valves moving as you rotate engine so when adjuster is as high as it can get it's on compression
 

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Discussion Starter #15
Before I retake the valve cover off and check my cam chain and valves I decided to run it again and make sure I had an idea where the sound was coming from. i did the screwdriver/plastic bottle hack in order to pinpoint the sound, looking on youtube some people with similar sounding problems said it was their rod bearing so I made sure to take a photo of where the noise was the loudest.
312500
 

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That motor had various issues but rod bearings (big end bearings) wasn't one of them unless it was run close to max rpm with dirty oil.
Tapping at small end is a different issue, low rpm operation means 'splash' lubrication isn't happening. Engine needs a minimum rpm to 'centrifuge' oil to the hole at top of connecting rod (in addition, underside of piston often has 'burnt' oil staining)
Probably 99% of the time, balance chain adjuster needs resetting, cam chain tensioner is 'stuck' and valves were adjusted on overlap.
I always did cam chain adjuster when valve cover was off, turn motor backwards just enough to see top of tensioner moving up and down. If it isn't moving easily, push on the top with a screwdriver but be careful not to overtension.
The balance chain quadrant adjustment can only be done with clutch cover removed
 
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