Bipes, Lycs & Vibration

[larryM]

Is it normal for a lycoming 360 biplane to experience a rpm range of increased vibration? I am trying to figure out if its an engine problem or harmonics. It smooth and minimal vibration except around 14-1700 rpm. Leaning has no effect, not mags, etc... I can't recall if it happened with my Pitts, but the Tiger Moth/Gypsy certainly did, but this feels abit different from what I recall.

Thanks,
larry

 

[TFF1]

 

[TxSkyBolt]

 

[Btro0515]

 

[StinsonPilot]

 

[Dave Baxter]

 

[larryM]