Yes it is if you haven't changed the pinion. I had two pinions that came with mine. Even the one with the lower tooth count was a bit too high for mine on 3s and caused it too overheat. YMMV
Check if your wheels/tires are balanced. That can cause serious vibrations.
Also loctite any screws that go into metal
Edit: what batteries are you using? I can’t find any batteries with 35C that’d fit in a merv