Bearing Replacement

[Bikemad]

I can't remove the controller, as the screws are rusted in pretty good. I would strip the head trying to get it out, which isn't a big deal, as I have a screw extractor. However, if they won't budge, there is no point and trying that either.

You shouldn't have to remove the controller as the bearing and cover should pass over it. The outer diameter of my controller was ~2mm smaller than the inner diameter of the bearing. 

Couldn't I just tap out the cover from the freewheel side ? Gently tap at it with a piece of wood or something, so as to not damage the inside of the cover ??

That should work to remove the cover and bearing but be careful not to damage the stator or magnets as they will no longer be kept apart if the freewheel cover is not fitted.
Try and keep the wooden drift (Piece of 1" x 1" or old broom handle etc.) as close to the bearing as possible and work your way gradually around the hub (or alternate the taps from side to side 180 degrees apart) to avoid tilting the bearing causing it to jam on the stator/controller housing.

If you heat up the side cover with a hairdryer or heat gun to expand the aluminium, you may be able to drift the cover off on its own, leaving the bearing behind, as drifting the bearing off the stator should be a lot easier than struggling to drift the bearing out of the cover after the cover and bearing have been removed as a single item. 

I would thread an axle nut onto the controller end of the axle (until it is flush with the outer edge of the axle) and then place the nut on a hard surface (using a scrap piece of wood to protect the surface) and then pack the wheel (not the side cover) so it is kept nice and level using blocks of wood, cardboard boxes or piles of books etc. while you drift the cover towards the hard surface.
This should hopefully prevent the stator moving in and out of the magnets each time you tap the drift on the inside flange of the the cover (the machined surface surrounding the outer race of the bearing).

Alan
 

[Adamsavage79]

Maybe I will try that. It does come out abit, but I don't recall if it was clear enough from the rest of the wheel to do heat it up, to get it off.

 I should also add that the motor is still quite loud and I'm not sure where the sound is coming from, or why. All I know is that it was fine until I was biking in the rain one day. When I replace the bearing and spun the cover on my finger, it was silent. So it must be coming from the controller side ? Can a bad bearing even produce that much noise ? It did seem like the sound was noticeably louder on the controller side, so perhaps it is that bearing.

Here is a quick video clip of what it sounds like: https://youtu.be/9TZMPxa-4Lg

Refresh my memory on how to remove the large bearing, once the side cover is removed ?

[Bikemad]

The noise in your video is definitely a bearing noise, but I've heard much worse. In fact, my freewheel bearings made a lot more noise than that. 
My noisy freewheel bearing was easy to identify as the noise would disappear altogether while I was pedalling but started again as soon as I stopped pedalling while the bike is still moving.

The small amount of noise coming from the bearings is being amplified by the large side cover because it tends to act a bit like a loudspeaker cone and will produce a much louder noise.

Refresh my memory on how to remove the large bearing, once the side cover is removed ?

I've never had to remove the large bearing from the side cover, but I suspect that a suitable bearing puller or a special drift may be needed to extract it, probably combined with some penetrating oil and a bit of heat.
If the bearing is really tight inside the cover, a manual or hydraulic press may be required.

It would probably be much better if the side cover could be removed leaving the bearing behind on the stator assembly, so that you could then drift the bearing off the stator by tapping the bearing with a solid drift.

It might be possible to initially drift the cover off the bearing by tapping in the same position between the same two stator spokes, but rotate the cover each time to gradually work all around the bearing housing part of the side cover. This will hopefully cause the bearing to tilt and jam onto the stator housing allowing the cover to be drifted off it leaving the bearing behind. 

Then you would need to drift on the opposite side side of the bearing to unjam it and then keep alternating from one side to the other until the bearing can be drifted all the way off.

However, if the cover will only come away complete with the bearing, it might be possible to place it in an oven and heat it up to expand the aluminium enough until the bearing simply falls out, although I don't know what temperature the paint will be able to withstand.

Unfortunately, if the bearing has to be drifted out, there is very little of the bearing that you can apply a drift to as the inner diameter of the cover is not much larger than the inner diameter of the bearing, and the bearing will probably have a radiused edge making it very difficult to drift against.

Good luck, and please let us know how it goes.

Alan
 

[Adamsavage79]

I'm going to leave this to my bike mechanic I think. He needs to rebuild the wheel anyway, so the wheel will be likely removed from the bike anyway. I recall that I was able to get the cover to come off abit, but not enough to get in with any of my tools. It was not far enough away from the rest of the wheel, for me to heat it up with my heat gun. If the cover comes off with the bearing, it looks like you can just tap it out gently bit by bit ? Or like you said, heat up the cover around the bearing so it expands just enough, that the bearing would either fall out or be much easier to remove.

[Adamsavage79]

Seeing as I have the controller cover off and I'm in the process of removing the controller, how difficult would it be to get the large bearing out ? I can see that the controller fits inside of it, but I have no idea if it will budge. Also, could I not put bearing grease around the outside of the controller, too prevent water etc from getting into the bearing and such ? I can see the dried water or salt, now that I have the controller cover removed.

[Bikemad]

I presume you have only removed the cooling fan and brake disc mount as the "controller cover" (the outer part with the cooling fins) is part of the controller , which you're still "in the process of removing".

I would  try to remove the side cover leaving the bearing behind and then apply some penetrating oil between the bearing and the controller housing before trying to drift the bearing off as previously described.

Adding some grease around the outside of the controller housing should definitely help to prevent both water ingress and further corrosion from the electrolytic process that will take place if saltwater gets between the aluminium housing and the steel inner bearing race.

You might want to also take a look at this post. Although the stator assembly and side cover is a lot different on the Smart Pie compared to the Magic Pie, the technique for removing the bearing should be very similar. 

Alan
 

[Adamsavage79]

I realized after, I still have the outside controller housing as well. I don't see how I would be able to pull the bearing off with that in the way. The only way would be to get the entire side cover off. Spring project maybe, or see if I can find someone in Ottawa that would be willing to do it.

Also, yes I have to still remove the controller. It does jiggle, so I just gotta play around with it. I had a stripped screw which I was unable to get out, so I had to pay someone to get it out for me. I just got the wheel back yesterday. I will get around to removing the controller this weekend sometime.