Turnigy 28-30 1000kv motor issue

[mkmitchell]

I had four of the Turnigy 28-30 and was using 1 of them for a plane while my quad parts came in. After crashing it a few times and lightly tapping the shaft back into place I noticed that it wasn't as smooth when turning it manually. It wasn't bad so eventually I moved this over to my quad. Over time (multiple crashes and I don't even know what else) only one of my motors spins free and smooth. I have 1 motor that takes quite a bit to get spinning and feels like it's bumping along as I spin it manually. The other 2 bump lightly but nothing compared to the one. I really notice this when I try to start all my motors up. The one that spins smoothly starts up with very little throttle. 2 start with a bit more and the last one takes quite a bit of throttle to start it spinning and it's noticeably slower. I replaced the bearings on the really bad one and I'm still getting the same bumping.

What could be causing this? I thought it could either be a slightly bent shaft or perhaps a magnet is sticking out a little too much.

Thoughts? Thanks for any help!

 

[Foam Addict]

I think you did bend the shaft a little on the really bumpy one.e
Just for grins, take the bell off the really bumpy one and gently pull out on the magnets, see if any are loose. The slow start up may also mean a broken strand of wire, which is not a huge problem, but you are losing efficiency if one is.