Quote:
Originally Posted by Z1R rider
You are holding the throttle wide open while compression testing I assume. Even with the throttle blades wide open the slides are still closed and it takes 10 or 15 seconds of cranking to get a good reading. If the reading is really that low, I'd guess the lap job isn't holding or cams are not timed correctly. Try holding the cylinders at TDC and blow compressed air into the cylinders through the sparkplug hole (leak down test) and hear were the air is escaping, into the crankcase (past rings) or the exhaust (past ex. valve)or the intake (past int. valve). If you are getting spark the ignition box is working.
PS: welcome to the site!
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I am not touching the throttle during compression test. Should I be?
As for the cams. I set the timing mark to #2 cylinder with the white mark on the rotor, intake cam lobes are upwards and facing the carbs, exhaust was facing up, but #2 cylinder valves slightly open, lines on both cams are parallel with the case (cam chain tensioner is installed for this). Am I missing something here?