Cyclotricity Revolver 250w front hub motor - bearing adjust / replacement?

[sheddyian]

Hi,

I've had a Cyclotricity Revolver 250w since Summer 2017, and use it regularly. It's obviously built down to a price and over the years I've had to replace some parts, but overall it's done me well.

The front motor hub has now developed significant play on the axle, but there doesn't seem to be a way to adjust the bearings as with a normal non-motorised wheel (no visible cup/cone adjustment).

I took it to a bike shop who also couldn't see how to adjust it.

IS there a way to replace/repair the bearings on the 250 watt hum motor wheel, or am I resigned to buying a complete new motor wheel ?

The play is significant!

(Attached is picture of motor hub with it's numbers, in case that's helpful)

Thanks



Ian

 

[saneagle]

Yes. That's an easy one to do. Just undo the side-plate screws and pull everything out. The bearings are in the side-plates. They're a standard size and have the designation written on them. You can get them form Ebay or maybe better quality branded ones from a bearing supplier.

The only problem I've had is when the bearing gets rusted onto the axle. I took a bit of 1/4 steel plate and ground a U-shaped wedge into it then smashed it under the bearing to push it up the shaft.

 

[sheddyian]

Yes. That's an easy one to do. Just undo the side-plate screws and pull everything out. The bearings are in the side-plates. They're a standard size and have the designation written on them. You can get them form Ebay or maybe better quality branded ones from a bearing supplier.

The only problem I've had is when the bearing gets rusted onto the axle. I took a bit of 1/4 steel plate and ground a U-shaped wedge into it then smashed it under the bearing to push it up the shaft.

Fantastic, thank you! I will take it apart tomorrow and see what it's like inside.

Thank you so much for your help

Ian

 

[Nealh]

Just as an addition once the side plate is off , there may be a nut and a flat seal on the opposite side to remove before the motor unit comes out. If it is tight simply use a hammer & block of wood on the LHS axle shaft to persuade it out.

 

[sheddyian]

Thanks for all your help. I've taken the motor apart today, but have a few further questions.

One bearing seemed to have a lot of play, and I've successfully removed that one by tapping it in a circular motion with a hammer and a punch. This bearing partly fell apart as it came out. Markings : 6001 RS L015 G&U .

The other bearing is stuck on the shaft, as you predicted. This is marked 16003 RS L015 C&U

There isn't much clearance between the stuck bearing and the electronics and other motor stuff, so I'm concerned I'll damage something using brute force. I don't have any metal to grind into shape to pry it with. Is there a suitable tool I might buy that would help me here? I don't really know what I'm looking for.

(This bearing doesn't seem to have play, although it does run a little rough, so I'd like to replace it while I'm here).

I noticed that there wasn't a great deal of grease in it, and what there was doesn't smell good. I will clean it all up with degreaser or WD40. Is there a particular sort of grease that's good to put back in it? I've got general purpose grease, otherwise I can buy something if there are better suggestions?

Attached are two pics, one of the bearing stuck and the other of the inside of the motor showing the comparative lack of grease

thanks for your help

Ian
(edit : typo in one of the bearing numbers)

 

[saneagle]

Oh dear, classic and common mistake. I can now see it in the first photo. You installed the motor upside down, which is what made it fill up with water. You're lucky the clutch is still working. The cable must always exit downwards, not upwards. remember that when you put it back in the forks.

Anyway, back to the stuck bearing. You should be able to pull it off with a three legged puller as long as you fold the cable right out of the way and don't have a puller with a very sharp point on the bit that goes in the axle. Put full tension on, then tap the bearing with a small hammer. A bit of penetrating oil on the axle might help. You can't heat it too much because the cable is in the axle, but a little bit might help.

 

[sheddyian]

Ah, I had no idea I had the motor in upside down, but I now see how water would trickle in that way. I looked at photos I took of my bike when I bought it, but can't see if it's always been the wrong way round as the cable is always out of shot.

Anyway, thanks for the advice, I've now ordered a 3 legged bearing puller that looks like it might do the job. Hopefully arrive early next week.

Thanks

Ian

 

[sheddyian]

Looking on the internet for suggestions as to what grease to use when I've cleaned up the gunk currently in there, I am very confused, so many differing opinions!

Eg lithium is bad for nylon gears, or lithium is best for nylon gears.

Can anyone tell me what they've used?

Currently it looks like it's got traditional multi purpose sand coloured grease.

Thanks

 

[saneagle]

Looking on the internet for suggestions as to what grease to use when I've cleaned up the gunk currently in there, I am very confused, so many differing opinions!

Eg lithium is bad for nylon gears, or lithium is best for nylon gears.

Can anyone tell me what they've used?

Currently it looks like it's got traditional multi purpose sand coloured grease.

Thanks

Lithium grease is good for nylon gears. You can't use an oil-based one.

 

[guerney]

Lithium grease is good for nylon gears. You can't use an oil-based one.

When the time comes to grease the nylon gears of my BBS01B, I was going to use Aeroshell 22, but this has me searching AliExpress for lithium grease. Thanks, that's bloody useful information.

 

[sheddyian]

It's taken me a while, but I finally fixed it and it's running great now, thanks to everyone for their help and advice!

When I last posted here, I'd got the motor apart and removed the smaller, most damaged bearing. But the larger one was stubborn and very close to the motor, so I couldn't prise it off.

I wrongly bought a three legged bearing puller, which was far too large to get under the tight clearance of the bearing.

I took the motor along to a local car mechanic, who spent some time looking at it but also failed to remove the bearing - their bearing removers were also too chunky.

I then found a two leg bearing puller designed for tight spaces, so ordered that.

This was a success. If its of interest, its "US. Pro Item 5152" - it was cheap but it worked well. (see picture)

The bearing came off slowly - but I had to keep untangling the motor cable which was winding itself around the bearing puller.

I'd already cleaned the rusty mess of old grease off the motor and the cogwheels with copious amounts of GT85 spray. I dried this off afterwards. I then put some LucasOil branded White Lithium grease all over the cogwheels and the moving parts in general.

Putting the new bearings on went well too - I used a socket (the sort for removing nuts and bolts) that was sized the same as the inner part of the bearing, so that I was only putting pressure on the part that was in contact with the motor shaft, not straining the bearings themselves. I hammered this in a circular movement until the bearing was seated. Repeated for the other bearing.

It took some tapping to get it all aligned, but it went without much problem, and I screwed the motor back together again.

I fitted the motor so that the cable was dropping downwards out of the housing, not upwards. Cable exiting downwards should help keep the water out!

And it runs beautifully now, so much quiter than before. And I seem to be getting better battery life too, I think it was under a lot of strain with the washed out grease.

So, thanks to everyone for your advice.

I've documented what I did in some detail here so that anyone else with bearing failure on this motor can see how I had success in fitting new bearings.

Ian

 

[Raboa]

I used this to remove bearings.

Pardon our interruption...

When installing a bearing it is advisable to hit the outer race, hitting the inner race can damage the bearing. You can use a long bolt to make a bearing press, attach the wide washer/ socket to one end and on the other end use wide washers and a nut. Tighten the nut and it pushes the bearing in, the advantage of this is the bearing is getting pressed in straight and helps protect the bearing and wheel faces. I appreciate this may not have been possible in this case, it sounds like you done a good job.

 

[Nealh]

Kudos to you for a good job done.