Loose bearing in cush drive
 

I was changing the rubbers in the cush drive (they were very worn).
I had a look at the bearings to check if they needed to be changed.

The one from the cush drive is spinning freely by itself on the outer race, without too much effort. Is this normal? The inner bearing race does not feel like it has seized.
What should I do? Put in a new bearing with bearing loctite, or buy a new cush drive part?

Here's a video of what happens: https://youtu.be/-zpfIqkuCXw

That is not good.

It looks like your carrier bearing has seized, and is spinning in the carrier. It is difficult to tell how easy it is to turn, or how much of the alloy carrier has worn away from the video.

I would start with a new carrier bearing (6304-2RS) and hope it sits firmly inside the carrier. If the new bearing doesn't sit firm then you are looking a at new carrier - depending how much slack is in the assembly.

Bearing "creep" is not normal and if it spins as freely as yours does in the housing then something is very wrong. It might even be that someone has fitted an incorrectly sized bearing in the past?

You could try using a bearing adhesive, which may work (for a short while), but you're only going to be hiding the symptoms of a greater problem. I would guess that, if it's been creeping like that for a while, the soft alloy of the housing in the sprocket carrier will have worn somewhat.

Probably worth trying a new bearing, perhaps with a bit of bearing adhesive; there might be just enough interference to hold it in place?

OK, clear opinions on that.

I'd rather not have to buy a new housing piece. I'll try with a new bearing and some bearing fastener first.

Otherwise, I could maybe deepen another 15mm out as on the Dutch forum, so a second bearing could fit in there, and perhaps stabilise the first one?
( http://www.motor-forum.nl/forum/list...46525#21446525 )

I don't think this alone is going to help if the housing is worn as, even with a 15mm deeper bearing, it is going to move laterally due the bore not being a uniform diameter. Even if it initially cures the rotational creep, the lateral movement will ultimately wear the housing further and the bearing will start to creep again.

If you don't want to buy a carrier, then one possible option might be to machine out the housing so it can take a bearing 1mm larger in diameter (whether that be the stock width or a wider double row type). You will then be able to reinstate the right level of interference and get the bearing to fit tightly. You'd obviously need to check first what bearing diameters are available before you start work.

I had a quick look, I could not find bearings which are 1-2mm wider in OD.

So I'll order a new housing piece. Question is then, would it be prudent to have that one machined to +5mm to have a double race bearing as has been advised on the forum? I don't want belts & braces, but I also don't want to encounter this again.

here's 2 possable options to use the flogged out carrier...
standard bearing 6304 20/52/15

1-
Put a 30mm bearing in 6006 30/55/13 is 3mm bigger in dia
so the housing wil need turning out 3mm & a spacer sleave
machined to press into the bore to bring it back to 20mm...
this bearing is 2mm narrower than the 6304 but the bore spacer
could be made with a 2mm flange on it to make up the 2mm..


2-
16006 bearing 30/55/9..
only being 9mm wide you could bore the depth of the housing
to 18mm to take 2 bearings... have a new spacer machined to
sleave the bore down to 20mm as well as replace the standard spacer
but go though both bearings..

The internal spacers will need to be a indeferance fit "press in"

hope this make sence to yer......

just a pitty you arn't closer as I could do the machining for yer...


Pete