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Discussion Starter · #1 ·
Is there a way to loosen the cam chain on a k5 cb450 enough to change the position of the camshaft so that the index marks line up correctly? At the LT mark the index marks on the camshaft and the bearing are not lining up(way off) but I would really rather not break the chain if at all possible.
 

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Sensei
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You MAY be on the "wrong" LT mark......It "hits" alignment twice on the four-stroke cycle.....You want LT on the left cylinder Exhaust stroke...Try rotating the crank ONE full CCW rotation until LT aligns again....And, yes it's possible to "skip" the camchain, but it's a real pain.....
 
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Discussion Starter · #3 ·
I was pretty sure that I had the left cylinder on the compression stroke but I went back through it again. The marks are still off. They are about 1/4 inch off on both the exhaust and the same on the intake. What is this about "skipping" the chain? How is that done?
 

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i would be interested in what people think on this one too... mine is off the marks a bit as well, but it seemed to me that if i skipped it one tooth then it would just be off in the other direction about the same amount.... is there a preferred way to be off? ie, have the valves opening a touch sooner or later than absolutely correct? same for intakes as exhaust?

or maybe my chain is stretched and a new chain would get me right on...
 

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Actually, the cam timing was designed by Honda to (thankfully) be performed NOT
on the top of the compression stroke - as we all know, it’s very difficult to keep the crankshaft in
place at the top of the compression stroke, it always tries to “run by”. This is a result of the
tension of any torsion bars that are being compressed, as well as the fact that the crankshaft rod is
actually mounted slightly off-center to the piston - this also tends to keep the crank moving at
TDC. So the actual cam timing is performed at TDC (Left) at the top of the exhaust stroke (just
prior to beginning the intake stroke). By this means, the crank will remain relatively stable and
the entire procedure can be accomplished quickly by one person.
In reality, there is no exhaust or intake stroke until the cams are in place, there's only TDC.
The cams are rotated to the (left) exhaust stroke when timing them up.

Trying to skip the chain by pulling off the cam covers is ill-advised, like Steve says.
You'll probably end up pulling the engine anyway after it doesn't work and you can't get it back together.
Get a new chain, and make sure it's the right one - they have little numbers stamped on them, make sure they're right.
 

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Sensei
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Sorry...Got compression on the brain after trying to tell several members their bikes WON'T run right at 120PSI......It IS at/on the exhaust stroke....
 

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It confused me at first - everything else is done on compression stroke.
This way the alternator will hold still for you, and you have both hands free to manipulate the chain and cams.
 
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Discussion Starter · #8 ·
Thanks for the warning tbpmusic. I would hate to have to pull the engine considering I just put it in. The chain I have is new and it is the right one. I replaced the old one when I replaced my pistons. I will just have to replace the master link.

Just out of curiosity how do you skip a chain?
 

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Sensei
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Remove both valve covers and the dyno cover.....Take off the chain tensioner assembly.... Take off the "teardrop" shaped plate on the top of the engine, and carefully push a smaller diameter "axle" for the top guide wheel to "sit" on..(a small screwdriver works well).... (basicly, you are allowing it to lift as the chain tightens) ... pull two links up in a "V" and catch the pin in the cog left empty by the pin that's now at the point of the "V"......"skip" the rest of the "slack" links down the cog..... Repeat until you have the correct alignment, insert the correct top-guide wheel pivot and secure it with the phillips screw.... Reinstall tensioner.... Remember to verify BOTH camshafts positions/alignment with respect to the crankshaft.
 
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