Originally Posted by rvbuilder2002
As I wrote in my other reply, if your static full throttle RPM is higher than your climb RPM then something is wrong. The flight RPM (even in a climb... should always be higher by at least a little bit but the actual difference depends on your climb speed)
As for your roughness issue, if 100LL did not solve it then the next thing I would recommend is inspect for debris in the carbs. It is somewhat common with a brand new build. Stuff can get flushed from the new hoses and lines into the carbs and often causes problems intermittently. It may even be in some way causing a slight power loss only in flight that is effecting your climb RPM.
Your max level RPM of only 5500 when the static is 5200 is another indicator that something is out of wack. A static of 5200 should cause a level full throttle to probably be above red line (5800)
Originally Posted by Azjulian
Scott - can I confirm your concern, from your message I'm reading that you would expect the static WOT RPM to be lower than the climb WOT RPM and then that cruise WoT RPM ?
We are just not seeing that here, I had a friend who has an SLSA RV12 check and his ground static WOT is 5500RPM, at 75knt climb out he is seeing between 53000 and 5350. Then in level flight WOT he gets 5600
Yes as indicated in my earlier post
More bad data I would guess because an RV-12 would be a horrible performer with a WOT static RPM of 5500. It is impossible to have a WOT static RPM of 5500 and level flight WOT of only 100 RPM more.
Doing a static RPM check with a wind blowing will give a false reading but to get a static of 5500 with a properly adjusted prop pitch would probable require the nose to be pointed into a 100 MPH wind so that is not likely the explanation.
Every RV-12 I have flown or worked on (at least a dozen I would guess) and every fixed pitch propeller RV I have ever flown or worked on has had a WOT static RPM that is lower than the WOT climb RPM. Basic physics makes that happen.
You are correct that the static RPM will be different from one day to another (or even time of day) because of the influences of air density, but the variation isn't typically very large unless you compare coldest day middle of the winter to warmest day, middle of the summer.