I agree it sounds just a bit too course, but maybe Tom is cruising around down low at 125 kts and just not telling anyone
Hi, I'm Doug in IL. In bound is hub replacement IAW theSeninich B revision exchange program. I bought my 12 built/used and it had a dynamic bal job 3 years ago. What to do now. I don't have dynamic balance capability nearby? Any suggestions opinions welcomed. I took the B hub off because of a 1.15 dif in blade angle and it's a b hub??
From my experience, anytime a propeller is removed from an engine (Rotax, Lyc., etc.) and then reinstalled, it will have some level of influence on the overall balance and that rechecking the dynamic balance afterwards is typically warranted.
If that wont be possible, you can label all of the parts positions so that is gets reassembled with the blades and the spinner reinstalled in the exact same clocking positions on the crank shaft and see what happens. If it feels as smooth as it has previously then you could just leave it as is. If not, then finding someone to check the balance would be a good idea.
P.S. I am somewhat hesitant to recommend this because physical evaluation of smoothness is very subjective. The only truly accurate way to know is to measure it. Having engine vibration low in an aircraft has many benefits far beyond passenger comfort (airframe longevity, etc.), so knowing for sure that the vibration level is as low as possible is worth traveling to have it checked in my opinion.
Also keep in mind that a very close match in blade pitch has a major influence on smoothness. Doing a dynamic balance without confirming that the pitch of the blades is within .1 degrees of each other is a waste of time and money.