I have some questions & hope someone can help
1. When the motor has a noticeable 'space' when you lift the top, do you have to 'toss' the motor? It looks like it is not repairable. I removed the C clip (which got lost in the carpet) and couldn't figure out how to fix it, or find another C clip.
2. A couple of mine get hot, and two do not. I put a drop of 3in1 oil in each one, and they are all cool now.
3. One of them stops rotating immediately when I cut the throttle, the others wind down in a second or two. Is this OK?
4. The carbon motor mounts for the X525 frame are worthless. a simple hairline crack and the motor vibrates like mad. They are way to flimsy with material cut away to reduce weight I suppose. Easy to break, especially on hard landings. :)
5. These were my first motors and I'm pretty pleased with them and their price. Are there others that I should be looking at?
Any/all help appreciated.
Bo Barry
Replies
Those NTM motors are pretty decent but come with terrible bearings.
I had one of those 28-26A motors seize up on the very fist flight due to bad bearings. If you can hear them making noise, or they "rattle" when you turn them by hand, you probably want to replace the bearings. I now do that preemptively for all of my mult-copters with small NTM motors.
If you have a hobbyshop nearby which sells Align helicopter parts, you will be able to find some nice 3mm bearings there which fit. I believe that motor uses 3x7mm and 3x8mm but it's safest if you remove a set from one motor and take them with you to make sure you get the right part. They will also have some helicopter bearing oil with a fine-tip dispenser to use on your motors in the future. While you're there, get some extra c-clips. E-flite sells them in 10-packs for a couple of dollars.
Put your motor in a large zip-lock bag while you work on it to keep from losing the c-clip. It's also a good idea to go to the local hardware store and get the proper tool to remove C-clips for around $15.
To remove the bearings:
Remove the C clip, take the case off, then using a small Allen wrench as a punch gently tap the two bearings out.
Your motors may have a small thrust washer. That should go between the c-clip and the bottom bearing.
When putting the new bearings in, just be nice and gentle to make sure they go straight in. Insert the front one, then slide the motor shaft in and insert the second over the shaft. You can just a small socket wrench to push on the bearing and gently tap it with a screwdriver handle or something to make sure it's seated well.
I don't know about that particular frame, but you should always replace a cracked motor mount.