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Hello everyone. I'm in the process of finishing up my engine rebuild on my CB450 K4. I was reading the manual for instructions on setting the cam timing. The manual just says stake the cam chain while the left piston is at TDC. Does this imply TDC on the compression stroke?
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Left cylinder tdc with the cam marks lined up will put you in the right spot. I'm not sure if it's the compression stroke or not at the moment. You'll have to pry the exhaust cam a bit because it is putting pressure on a valve at that point. A brass vice grip would be handy but the imagination is a great tool.
 

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Make sure you have identified the timing marks. Depending on the mood of the factory tech, they can be very lightly marked. The mark can be easily missed and mistaken for a casting line. This caused me a huge amount of grief.

This chart is from the CB450 FSM. It took me some studying to understand it. Bubble #1 is cut off. but it is the line at the very top. It represents the 720 degree rotation of the CB450 DOHC cycle of the left cylinder. The right cylinder follows 180 degree behind. As lefty says, when the left cylinder is at TDC, the right cylinder is 'on the ramp' of the right exhaust closing.

Valve-ignition Timing Swirl.jpg
 

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There is no compression stroke until the cams are installed and timed..
Cams actually get set to the in-between stroke - the exhaust cam needs to be rotated clockwise (from rider's left side) quite a bit from its loosest point to its timing mark.

My offering......
 

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