Pedals go round but won't turn the wheel, no fault with the chain.

[Synthman]

Today I noticed when I pedal it felt like the chain was slipping off, and eventually it stopped working completely. I only pedal on steep hills and to help the bike accelerate from a stand.

I was expecting the chain to be hanging off completely but it was seated perfectly and going round normally. It seems the part on the rear sprocket that lets you pedal backwards (freewheel?) might be faulty.

I have no idea what to do with it, or if my local bike shops will be able to fix it, especially if the wheel needs removing. I might try lubricating it tomorrow and see if it helps.

 

[flecc]

It sounds as though the freewheel has failed, but the local bike shops can repair it. You haven't identified your bike so I cant give exact details for you. If it has a derailleur gear with several sprockets at the rear on a rear hub motor, the whole freewheel unit will be replaced, and the same goes in the unlikely case that it's single speed bike.

If it has a derailleur gear but no rear hub motor, just the freewheel inner of the cassette will be replaced.

If it has a hub gear unit, that will need to be repaired or a replacement inner or hub fitted.

 

[Synthman]

It is a rear hub motor with a single gear. Looks similar to the Golden Motor ones, and are quite common on Chinese bikes.


Same design as this, but black.

 

[flecc]

In that case it's a simple replacement of the freewheel, not expensive. It may be a standard or BMX type thread, but a cycle shop will know which.

Some cycle shops are anti working on e-bikes, but don't be put off by that since there's usually at least one in any area which is happy to do so. If the cable that connects to the motor feeds into the spindle centre on the freewheel side, the cable will have to be disconnected to fit a new freewheel, but there's usually a connector to facilitate that.

Let us know if you meet any difficulties in getting it fixed.

 

[Synthman]

Hi flecc, today I went about the last of my business on the bike as usual, and I tried oiling it, which didn't help. However if I rotated the wheel backwards, the freewheel would engage/disengage for a bit then would stop working again.

I took it to a local e-bike dealer who said they could do it, but firstly they need to identify and order the part, which would take at least a week and at then about 2 hours labour, and probably another week, and would cost over £100.

I then took it to my local bike shop, who have done 4/5 repairs on it in the past, and they said it was a BMX freewheel, and they gave me a more reasonable estimate and said it would be ready tomorrow afternoon. So I've left the bike with them and I hope they won't have any trouble regarding the electrical connections.

I recently took the bike panels off, and behind the headlight, and all connectors on the wires have neat connectors that slide apart, so hopefully the rear wheel is the same.

If they can't do it then I would go for the other place, the main concern being the timescale, I could manage a few days but not anything more than a week without it!

 

[Synthman]

One other question. How long do these freewheels last? My bike has done well over 2000 miles now, and recently I heard a faint grinding noise coming from the back wheel so that could have been advanced warning that the freewheel was failing.

 

[flecc]

Normally they outlive a bike, but as with everything, one gets the occasional dud. I think you were just unlucky. There are very large numbers of the eZee Quando e-bike on the road over the last 7 years, all using BMX freewheels, but I've never heard of one failure on them, and I run an eZee Quando and Torq 1 support website.

I'm glad you located that second dealer, the first one's quote was unreasonable in every respect.

 

[Synthman]

My bike is now fixed. They fitted a new Shimamo SFMX 3016 freewheel, which is around £20, and the labour was £14.40. The only thing I noticed is there seems to be more drag on the back wheel at the moment, and the brake is rather tight, but I don't know if this will go away if I slacken the brake cable a bit.

 

[flecc]

That's almost certainly the brake, so try slacking it off a bit. If it drags the freewheel around afterwards, there's a very slight possibility that the freewheel outer is fouling the motor side plate, but this is rather unlikely.

 

[Synthman]

I've slacked it a bit but there is still a very slight resistance. Well there always was with the bike but it seems a little bit more.

There is a faint rubbing noise from the hub brake though. Later on I'm going to ride it some distance and see what happens.