Dirty rusty bafang hub

[Scottyf]

Unfortunately not, couldn't see any numbers as it had rusted through and Broken up.
Might just give it a rinse with petrol on various parts and then pack it with more grease once I get the new bearings.

Inner race will be the size of that ring on the second to last picture. While the outer race will be slightly under the circumference of the 4th picture. Width should be the same as the last picture. Once I get it off.

The bearing did completely split down the middle though. Maybe with the water and me jumping of curbs has cause alot of fatigue on the bearing. However gears and windings are good

 

[Scottyf]

Bearing Sizes for the Bafang BPM Rear Driving Motor :-

RHS Bearing (As you look at the front of the bike fitted) FREE WHEEL SIDE
6810RS (50mm id, 65mm od, 7mm wide)

LHS Bearing (As you look at the front of the bike fitted) BRAKE DISK SIDE
6904RS (20x37x9mm)

 

[wurly]

How are you going to get the remains of that inner bearing off? You might need to measure the ID of the bearing before you can find a replacement....useless you can measure it without.
I would use a bit of heat and try to get some thing thin (like a blade of a knife or chisel) and try to get some movement first and use some penetrating oil. It's going to have to come off eventually.

 

[jayuk]

Hi scottyf

I have a bpm hub motor that has a snapped spindle for sale as spares.

Jay

 

[Scottyf]

The engineering firm will take it off or chisel it out. If I had a vice and anfew of those tools I would. But as I live in apartment all my bigger tools are at my old house.

So it just have to make do with the basics then pay someone else to do the harder stuff. It's a bit rubbish but it's all I can do.

 

[jayuk]

i think i only done about 450 miles on it.

 

[wurly]

How did the spindle snap Jay? i wouldn't mind it if Scotty doesn't end up using/buying it.
Scotty has first dibs of course.

 

[Scottyf]

It's fine my motor is ok. Gears, clutch windings all perfect.
Dirty and messy but working none the less.

So all yours if you like.

 

[Scottyf]

If I had to do it my self I think i'd just buy a small hacksaw and cut through it to remove it.
That would seem like the easiest way if i couldn't knock it out.

Or angle grind it down, but that would probably be a bit aggressive.

 

[Hurricane]

If I had to do it my self I think i'd just buy a small hacksaw and cut through it to remove it.
That would seem like the easiest way if i couldn't knock it out.

Or angle grind it down, but that would probably be a bit aggressive.

A hacksaw would not make any impression on it as a bearing is hardened steel. A good solid hit with a chisel usually splits it and it then comes off no problem. Angle grinder is okay if you can get cutting disk in without damaging anything else

 

[Deleted member 4366]

Scotty, how can any self-respecting bike builder like you not have a Dremmel (or the Aldi cheaper equivalent)? You get mini grinding disks with it that'll have that off in seconds with no damage. Put one on your next birthday or Xmas list.

 

[Mussels]

Scotty, how can any self-respecting bike builder like you not have a Dremmel (or the Aldi cheaper equivalent)? You get mini grinding disks with it that'll have that off in seconds with no damage. Put one on your next birthday or Xmas list.

That would be the first tool I turn to. You don't need to grind all the way through risking damaging the axle, grind a slot most of the way through over the whole length, put a screwdriver in the slot and twist to release the old bearing.

 

[Scottyf]

I know you'd be amased what I manage with in a small apartment.
I have various other tools and weird things in storage. Which is a right pain. Fortunatly electric gear has mostly forced me to buy new things which i've never had before.

Maybe I'll just buy one and give it a go. I thought at worst I could always use a mini hacksaw to get the actual inside diameter out anyway.

Tools are one of those things you just seem to accumilate over time.
Some of the old ones are definetly the best ;-)

 

[jayuk]

Hi Wurly

I have no idea what made it snap! i was only ever using the mtb on cycle tracks, not bumping up & down curbs or anything like that. It actually look like it sheared off & obviously took the cables with it, & yes i had a torque plate lol, Which parts would you like, i no a few of the spokes may be missing from the full wheel. make me an offer if interested as i no longer need this not even for spares as i changed over to a mac 500.

thanks
jason

 

[wurly]

P'med you Jay

 

[jayuk]

Hi Wurly

i have tried to send address details but it says your mailbox is full.
hopefully you will see this message to let you know, if not hopefully someone on the forum can pass this onto him.

thanks
jason

 

[wurly]

Blimey....these inboxes fill quickly
Sorry 'bout that, i didn't realise.
Empty now, can you resend your address Jason, thanks

 

[jayuk]

pm'd wurly

 

[Scottyf]

New bearings fitted.

Ended up angle grinding the remainder of the race off. Then whacking it with a chisel.
Also swapped the smaller bearing as it was cheap and only a couple of quid for an skf obe in that size.

All in all it's cost £24 for the bearings.

However I do need to re grease it. Also it's quit audible to rotate now its been cleaned.
Is this just the lack of lube or is there a bearing inside the housings that I could swap out?!?

 

[wurly]

Well done Scotty. I hope you kept the swarf from the grinder off the magnets?
Bearings are pretty cheap, and i guess the ones you needed were readily available?
I can't think what might be making the noise, unless it's the one showing in your photo of the housing, did you change those as well?