Chain coming off front sprocket

Boff

Finding my (electric) wheels
Jun 10, 2019
11
5
I have a Haibike treking1.0 Bosch Active line plus. 3 times the most recent the chain has come off the front sprocket and wedged between the sprocket and the motor cover. It is stuck fast the only way apparently to remove it is brute force and ignorance it is making a mess of the cover. These seem to be 0mph incidents I wonder it it is a bit of reverse peddling to find a starting position maybe coupled to a higher gear say 4th Just wondering what I can do to stop it happening.
 

soundwave

Esteemed Pedelecer
May 23, 2015
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how old is the chain?
 

Boff

Finding my (electric) wheels
Jun 10, 2019
11
5
The first time it did it the chain must have had less then 30 miles on it today around 250 miles
 

soundwave

Esteemed Pedelecer
May 23, 2015
16,897
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could be to long if it is that new, never had it on my haibike tbh.
 

Andy-Mat

Esteemed Pedelecer
Oct 26, 2018
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I have a Haibike treking1.0 Bosch Active line plus. 3 times the most recent the chain has come off the front sprocket and wedged between the sprocket and the motor cover. It is stuck fast the only way apparently to remove it is brute force and ignorance it is making a mess of the cover. These seem to be 0mph incidents I wonder it it is a bit of reverse peddling to find a starting position maybe coupled to a higher gear say 4th Just wondering what I can do to stop it happening.
Have you ever had the rear wheel off to repair say a puncture?
If yes, the front to back chain alignment may be off now.
Its the only thing that I can think of, I am assuming that the chain was not kinked or damaged by the first "off"....
I hope that helps.
Andy
 

mike killay

Esteemed Pedelecer
Feb 17, 2011
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The chain often comes off the front chain ring on my folder bike. Generally if I have folded it, so I always leave it in a middle gear when I park it.
 

Boff

Finding my (electric) wheels
Jun 10, 2019
11
5
The chain often comes off the front chain ring on my folder bike. Generally if I have folded it, so I always leave it in a middle gear when I park it.
I guess that this is what is happening to me. What pee’s me off apart from it coming off is the way it jams. It seems to me if the cog was just a couple of mm further in our out relative to the fame. Then when it came off it would either not jam in the gap or alternatively if the gap wider, it would fall throug and not jam.
 

Boff

Finding my (electric) wheels
Jun 10, 2019
11
5
Have you ever had the rear wheel off to repair say a puncture?
If yes, the front to back chain alignment may be off now.
Its the only thing that I can think of, I am assuming that the chain was not kinked or damaged by the first "off"....
I hope that helps.
Andy
Sorry I didn’t reply earlier. But no, I haven’t removed the back wheel. Weh
bought his n hers bikes hrs is the smaller frame but otherwise identical and hers there hasn’t been a problem. We got them from Cycle republic, in Liverpool in January. I’m not sure they had indexed the gears quite right. After a few rides I realised that I couldn‘t get 1st gear , it may have been like that from the start it might not have been. Sorted that and tightened up the light apart from that they have been all good.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
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West Sx RH
Try a chain keeper.
 

georgehenry

Esteemed Pedelecer
Nov 7, 2015
1,446
1,264
Surrey
Something wrong for this to happen to a new bike.

It happened to me when I had a worn out rear hub.

Likewise when the whole drive train was getting very worn out.

Completely stopped when I replaced the drive train and included a narrow wide front chain ring, and I have a hard tail mountain bike that I use a lot off road with lots of bouncing around and quite hard hits.

One of the best cures with a single chain ring set up is to put a narrow wide chain ring on the front.

But it would be better to find out why it is happening first.
 
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Amoto65

Esteemed Pedelecer
Jul 2, 2017
807
502
61
Cheshire
Something wrong with the setup from new, I have done 2500 miles with an Activeline plus motor and had no problems, a competent bike shop should be able to sort it if you can't as it is only a running gear problem and nothing to do with it being an e-bike.
 

Darren Hayward

Pedelecer
Mar 25, 2015
93
47
61
I had the same. Went to Evans who explained the derailleur has a clutch and mine was in the off position. Doh!

There should be a lever on the derailleur arm that makes the arm stiffer, so the chain stays tighter. Check that.
Any bike shop should spot that straight off, so if it is that don't go back there.


Darren