Sticky Hub

[Ben Stone]

Perfect, I think I will have to bite the bullet you say and wheel the bike round to a local mechanic. I am sure they will be able to help. I will also ask about the screws on the rear side of the hub too.
I am just trying to put the bits back together so I can wheel it round and now I cant get the hub back into the cogged housing? Is there a special knack to this or is it just trial and error? It popped out using some force, I am concerned I might not be able to get this back in now!?

 

[shemozzle999]

Hi Ben,

You could just take the motor to them they would not need the whole bike.

If it came out it will go back

Lightly clean up both the stub axle shaft with your wire wool to remove any corrosion off the surface also the inner race of the bearing located in the housing containing the ring gear, lightly grease both and then insert the stub axle of the motor assembly into the bearing, it should be a push fit. it might need jiggerling about so the 3 planet gears align and locate with the ring gear teeth.

 

[Deleted member 4366]

That's a common problem on hub motors and easy to solve. The problem is that the ring gear in the hub is fixed, but the ones on the motor can turn. You need to set the motor so that the furthest out teeth are on a radius, i.e. the tooth has to be in line with a line directly to the centre of the axle. If that doesn't make sense, try and imagine how the teeth are going to slide into the slots in the ring gear.

 

[Ben Stone]

thanks both for your kind advice.
I will give it a go today and try wheel it round to the local mechanic so they can give the hub screws ago.
As you say if it come out, it should go back!

 

[shemozzle999]

Hi Ben,

I hope all goes well.

I must add that although I was never charged I have always made a small contribution to the "drink" fund, I found it helps oil the wheels if you ever need to use their services again.

 

[Ben Stone]

As you can see we managed to prize out the perimeter screws on the rear of the hub! Do I need to remove the 6 central screws around the axel too?

 

[shemozzle999]

I see no harm in freeing them up also because you mentioned that the power cable was worn and if you are considering replacing it now or in the future it will make the access to the cable easier. I would also loosen the 3 screws I can see holding the brush assembly plate

Did you manage to get the 3 holding on the stub axle on the other side off?

 

[Ben Stone]

Hi Shemozzle,
Firstly, 3 holding screws on the other side are still unfortunately stuck. The mechanic had a good go but was unable to get sufficient grip. A little bit frustrating! As mentioned I was able to get behind the plate and give everything a good clean, it just means I cant access planet gears to replace.
However the perimeter screws are out as shown but the hub is still firmly stuck together. I wasnt sure whether those central 6 screws were also holding the plate down or are they just connection for the axel? Out of the 5 we were able to loosen 5 of them with the 6th firmly stuck! I was hoping I could prize the hub open with just the outer screws removed. I was further hoping its just rust holding it together?

 

[shemozzle999]

I think they only hold the axle on that is how my old brushless motor is constructed - shame about the other side though - I think it might be the source of your problem - still if all the planet gears still have all their teeth a coating of new grease might quieten down the motor.

You might still need access to the other side to determine how the sun gear is attached and whether it needs to be removed to allow separation of the 2 halves of the inner motor shell.

 

[Ben Stone]

Teeth are looking nice and sharp on the cogs, a little dirty but they have cleaned up nicely.. I will give them another go later.
I will keep trying to prize the back off, do you think its worth it or should concentrate on getting the 3 screws off the planet plate?

 

[shemozzle999]

My priority would be the 3 screws, until you can expose the sun gear you have no way of knowing if it is stopping the separation and prising the 2 apart might cause some damage.

 

[Deleted member 4366]

Those three screws are probably stuck in the aluminium housing due to corrosion. The normal way to shift them is with heat, but you can't use enough heat because the plastic gears would melt. If all else fails, you can drill the heads off. That will allow the plate and gears to be removed, Then, if you could get a small hot flame, like a silver-soldering torch, you could heat up the stubs that are left behind to red hot so you can remove them easily with mole grips.

 

[Ben Stone]

Hi D8veh, Shemozzle, I appreciate the advise, but I think even for me this might be a little too much for me. I dont want to damage the planet cogs.
I have just tried the 3 screws again on supporting jig so I can get enough purchase but they arent moving! My plan is to clean everything up as best I can and re-assemble. Annoyingly I think it probably is a worn bearing or 3 on the planet gears. Its all moving nice and smoothly now, just seemingly quite loud, although i guess this will reduce once the housing is sealed etc.
Thank you both for you never ending supply of advice and support!!! I wish you both a nice bank holiday weekend! if you are ever in and around Wokingham I will be happy to buy you both a few pints!

 

[Ben Stone]

Re-assembled and its all working. I must say its running smoother and quieter than previous, but with still an obvious whir.
Its much better now and I have learnt a lot - again!
Thanks again both, I hope to be out on my bike this weekend now!!
A happy pedelec!

 

[shemozzle999]

Well done on your perseverance Ben many would have given up and thanks for adding to the Sites knowledge base.

Don't forget to seal the power cable entry point to the motor with some mastic sealer as this was the main cause of your problem - allowing water to get into the motor.

Shame about the screws but you have succeeded in getting it going again.

I have also learnt something new while researching your problem - how to make your own penetrating fluid supposed to be much better than any commercial product:

Using an old style metal (will melt plastic containers) oil can dispenser mix 50% low viscosity transmission oil with 50% acetone. shake before use.

Enjoy your new rides.

 

[Deleted member 4366]

Using an old style metal (will melt plastic containers) oil can dispenser mix 50% low viscosity transmission oil with 50% acetone. shake before use.

Now I've learnt something too. In my experience, penetrating fluid works very well for steel bolts into steel or cast iron, but if you have corrosion of a steel bolt in aluminium, the only thing that works reliably is heat.

 

[Nealh]

For a sealant the ones that go hard or rubbery such as silicone I find useless, I prefer a non setting type that remain water resistant and sticks like sh*t to a blanket. Initially they are tricky to use being very sticky and elastic but after 24hrs form a skin whilst remaining pliable/.mouldable without further gooeyness butyl 145 sealant is good once you get used ot its characteristics.

 

[Swytch Bike]

Thanks Robdon, I will check them out, much appreciated.

Hi Ben did you find what you needed from us?

 

[Ben Stone]

hi Panda,
I managed to repair my bike, well its running and I ve been cycling to work this week in the lovely weather,
One thing I have noticed is the "power" the bike/motor offers me has somewhat reduced. Its seems ok, but a steep hill and the motor really does struggle and offers little assistance in comparison to before. I am using my gears a lot more now which is fine but wondered if there is any way to check or improve power for the motor? battery is looking ok (its only 12 months old) so assume it must be either controller issue or again, back to the hub.
Any advise, help gratefully received.

 

[D8ve]

What has happened to the range/speed?
If it's the same then you have a new loss in the system. If range has increased or speed fallen then sensor/ controller?