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While the valve cover is off. Rock the crank back and forth. Watch the cam. See how much you can rock it back and forth before the cam moves. That will give you an idea on timing chain stretch.
 

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1986 Rebel 450
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Discussion Starter · #22 ·
View attachment 115708

timing chain has spring loaded mechanical tensioner that sticks up under rocker cover.. tap down on it to assure wedges are loose enough to self adjust..
View attachment 115709
That large wedge is supposed to spring down? The larger one doesn’t budge but the smaller one springs down. I noticed that when I was trying to remove the cover
 

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1987 CMX250C AC
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yes both wedges should move.. raising wedge A loosens pressure on tensioner
Motor vehicle Font Automotive exterior Auto part Photo caption
 

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Discussion Starter · #25 ·
Okay….So let’s just say I have the cover off and I go to push down on wedge A and it doesn’t move at all but wedge B springs down. Is that a problem. Or does the cam have to be in a certain position and or have to have the cylinder head off ?
 

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Discussion Starter · #26 ·
Okay….So let’s just say I have the cover off and I go to push down on wedge A and it doesn’t move at all but wedge B springs down. Is that a problem. Or does the cam have to be in a certain position and or have to have the cylinder head off ?
I’m wondering if mine is jammed also. Hmm
 

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Tab should move down.. whack down on it with screwdriver handle
I used a small ball peen hammer
 
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Discussion Starter · #28 · (Edited)
Tab should move down.. whack down on it with screwdriver handle
I used a small ball peen hammer
I will try that if I can get the cover off. That larger wedge doesn’t move so I can’t spring it down to get the cover off or on. Have no clue how it came off the first time but it took me damn near 3 hours to get it back on. I had to lower the engine. It kept getting stuck on that wedge that doesn’t spring down while trying not to destroy the gasket that no one can get anymore
Automotive tire Motor vehicle Gas Machine Vehicle
 

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1986 Rebel 450
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Discussion Starter · #29 ·
I was just reading the manual and
Hand Bottle Tire Automotive tire Automotive lighting

White Black Font Line Material property

it says knocking could be caused by excessive carbon build up. When I rejetteed the carbs for the exhaust I went for a ride and came home, took the plugs out and they were black and sooty. Then the knocking started right after that ride. Is there a way to remove the possible carbon with a oil additive? Seafoam / marvel mystery oil? A fuel additive? It’s a shot in the dark but I have no idea anymore. Lol. Ever since it knocked I returned everything back to stock
 

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BYT (Before YouTube) Old school decarbonization was to trickle water into intake while at higher rpm..
guess some still use it..
 

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1986 Rebel 450
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Discussion Starter · #31 ·
Thanks. I tried spraying sea foam top end cleaner onto the valves and into the spark plug holes. And ran the engine alittle but it didn’t do anything. I also found this video I made when I was trying to get the valve cover back on. It shows what cam adjuster moved and what one didn’t spring down. Just a piece of video that shows it. I was having a lot of trouble getting the cover back on.

 

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1986 Honda CMX 450 Rebel
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To get the valvecover off and on, it´s nessesary to remove the ignitioncoil/CDI.unit and cableconnectors. To do that it´s okay to remove the bracket wich holds the whole shebang. Hold it up with a rubberband or the likes.
Behind the valvecover is an bracket which holds the cylinderhead. Only the right triangle part can be removed (do that !)
All this, just gives enough space to maneuvre the Valvecover on and off. Still be careful in handling the cover and gasket..

To check and adjust camchain tension, loosen th two M6 Bolts (just loosen them don´t screw them out !) behind the cylinder-head and cylinder. Than turn the crankshaft counterclockwise. Holding the crankshaft under light tension, the M6 Bolts can be tightened again The hexbolts are M10 for the spanner-width.
Camchain-tension should be correct know and further manual tensioning isn´t nessesary.

good luck !
 

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Discussion Starter · #33 ·
I adjusted the balancer chain and the self adjuster adjusted itself. It moved up alittle. It was at the bottom. But knock is still there. I was Just wondering if it’s normal to see the exhaust valve when it’s opened through the spark plug hole?
 

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Discussion Starter · #34 · (Edited)
So I bought a mechanic’s stethoscope and the noise seems to be coming from either the bottom end or the valve cover. Not sure if the noise is just traveling or what. But still hard to pin point where it’s coming from. I did notice when I attached the shifter back on the bike without the cover that the shift rod that goes into the trans has play in it. Please See video below. I’m not sure if that’s normal or not or if it’s just because the cover isn’t on Because the bike did fall into the dirt and then the knocking appeared. So I was checking the bottom end and what could maybe cause the knock. Just not sure if that rod flexing is normal or not.

 

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1987 CMX250C AC
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oops, forgot you have a 450
looks like the bore through side cover provides support needed
The 250 Rebel has an inset roller bearing where the shaft passes through left side cover..
 
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Pete has good idea loosening assembly and rotating counter clockwise
is wedge doesn't retract tap it.
Wedge you couldn't move fully retracted along with housing it's attached to in this image..
Tool Composite material Wood Metal Gun barrel
 
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Discussion Starter · #38 ·
oh okay. Thanks. I didn’t want to battle with the valve cover today. I will try and get it done Tommorow and hit it with the small hammer. If not I’ll try and see what Pete is talking about while looking at it. That bigger wedge is stuck up. I’ll put some wd40 on it and hit it with the hammer Thanks for the picture!
View attachment 115716
[/QUOTE]
 

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That´s a No Go ! Don´t use any Force like a Hammer on the camchain-tensioner !
 
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