I recently had reason to replace the tail rotor drive on my 400. All repairs went well thanks to the instructions on the site, but there was still a vibration in the tail. I replaced the tail drive shaft inside the frame, time consuming but easy, and then, while replacing the tail rotor shaft (in the tail case) I noticed what seems like lots of slop in the bearings. These are the bearings that are pressed into each side of the tail case. It looks like the manual calls them 2x5x2.5 mm bearings (part EFLH1464 or EFLH 1466 for the pair) but these CAN'T be the correct ones, the shaft doesn't even fit through the hole!
Can anyone tell me which bearings are the ones for the tail case? One fits in each side of the tail case and each end of the tail rotor shaft (EFLH 1465) rides in the bearing.

I answered my own question by calling horizon Hobby. This part is listed wrong in the manual. Item 128 is NOT EFLH 1464 - 2x5x2.5 mm bearing, it is actually EFLH 1115 - 3x6x2.5mm bearing. That makes sense. I'm calling my LHS to see if they have it in stock so I can get back in the air!

Hi Gino,

You are right and the parts list is wrong. The tail rotor shaft is 3mm dia. so the bearing must have a 3mm hole. I tried downloading the latest list from here, but it is no different to my manuals' list.

As the bearing must have a 3mm hole the only ones that I can see in the tail section are [117] Bearing 2x6x3mm (4) EFLH1121; but only 2 are shown not 4. Could be that these are the ones used in the tail housing as well as the tail blade holders and someone numbered the housing bearings 128 by mistake. That part MUST fit elsewhere but I don't see where yet.

Try checking the 117's against the housing bearings they may well be the same ones.

Keep us posted this is interesting.

I got the 115s. Perfect fit. These are the ones. There is still a small amount of slop, the shaft isn't quite as snug as I would think it should be, but performance is back with no high-frequency vibration in the tail.

I haven't checked the 117s, but don't need to now.

Don't even think about it Gino, you've got the right ones there and I hope we are all noting this in our manuals. The first digit must be the inner bearing diameter, pity that wasn't written in the manual somewhere, it would have helped a lot in solving this problem.

Thanks for telling us all .

Gino, it's good too see you out there. How is the flying going? Still waiting for a video.

Crash.

Crash - Actually, I'm getting a lot better. I'm still practicing hovering in different orientations, but I hover tail-in with complete control, even in a moderate wind. Not quite as comfortable with side and nose-in, but it's coming along. repairs are a lot less frequent.
Once I can control forward flight, I will get my better half to shoot a short video.