Really high idle

[dave]

My question to you is; did the faulty iacv operate normally in the startup cycle and were the rpm's of the engine as you would expect?

Hi Max. My engine idle RPM was inconsistent and unpredictable. I never experienced a problem when the bike was first started (completely cold engine). After the engine was fully warmed up the idle would sometimes go as high as 1,800 RPM, and other times it would "try" to idle as low as 500 RPM, and then stall (I could keep it running by twisting the throttle). This problem would come and go completely unpredictably - it did NOT appear every time the bike was ridden. When the problem occurred I tried all of the tricks (turning the ignition off, performing the TPS reset by twisting the throttle), and nothing worked to eliminate the problem. Shutting the engine off and restarting it would "sometimes" cause the idle RPM to momentarily return to "normal", but the problem would immediately return when I would reach the next stoplight (mostly turning the engine off and restarting it would do nothing.) If I had a torque watch (I used to use one at work) I would measure the torque to rotate the IACV, but I don't. I'll just keep my old, defective IACV sitting in a box for now and maybe someone, someday will like to perform some new tests on it.