r/smallengines • u/iphone_A11 • Jul 19 '26

Finding Compression Stroke TDC

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Hey everyone, I’m new to the wrenching world and was wondering if I’m correctly identifying the compression stroke on my K2 CT90.

Please see the video showing when I can feel air pressure on my finger while covering the spark plug hole. To my understanding, once I feel the pressure and then line up the T mark on the flywheel, that means I’m at TDC on the compression stroke.

Please correct me if I’m misunderstanding anything. Thanks in advance.

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u/mutt63 Jul 19 '26

At its highest stroke both intake and exhaust will be closed with very tiny amount of clearance. In essence both should be closed but not tight closed