Sorry! You are looking at the KACR, from the end of the exhaust cam. The 2 flyweights ( held together by the spring) spread apart by centrifugal force as RPMs rise, thus allowing the valve to totally close. To artificially keep them open during your test, open them with your fingers(they kinda lock together, move one and then the other) then insert the tubing between them and under the spring. As in my pic it doesn't necessarily need to be under the spring, just holding the flyweights open. Don't forget to ground the spark plug during the test to prevent damage to CDI unit and make sure throttle is wide open for full flow of intake.