New to pedelec have a 2nd hand cyclotricity revolution

[Newbie607]

Using it to get to work most days instead on my BMW 7 Series diesel. So saving the planet...

Works ok mainly but assisted pedalling is sporadic. Well, more off than on meaning I have to use the throttle to get help up hills and I have some big hills to climb home. I have mailed Cyclotricity but any thoughts from you experts?

 

[Andy Bluenoes]

Could it be the pedal sensor not lined up correctly?

 

[Deleted member 4366]

Almost certainly the pedal sensor magnet disc has moved away from the sensor. You can just slide it back into position. If it's not that, it's possible that when the chain jumps off the chain-wheel, it damages the sensor's wire, so have a good look at that.

 

[Newbie607]

Could be. But to me that may as well be a dilithium crystal fault! Any idea how I would check?

 

[Newbie607]

Almost certainly the pedal sensor magnet disc has moved away from the sensor. You can just slide it back into position. If it's not that, it's possible that when the chain jumps off the chain-wheel, it damages the sensor's wire, so have a good look at that.

Thanks. I will have a look see. Once I work out what a pedal sensor looks like. Google here I come.

 

[Andy Bluenoes]

Im sure d8veh will give a much clearer answer, but there will be a small disc on your crank which has magnets in it. It spins with your pedalling...it should have a nice unifrom gap between that and the small sensor attached nearby....with a wire going to your controller. The gap needs to be a few mm evenly all round. Ive had mine get knocked a few times here and there and it causes the problem you have.

 

[Newbie607]

Thanks for all the help folks. Lovely intro to the forum - really appreciated. I will let you know how I get on.

 

[Newbie607]

OK. So had a look at the thing. Wiring looks sound. I may open the controller later and just look at the connection. However, the disc moves quite freely on the crank, it isn't locked in place. Looking at the e-fit instructions it appears to me it should be fixed. Is that right?

 

[Nealh]

Don't open the controller as there is no need, a mag pas disc floating about will not be sending a constant proper signal to the sensor. The disc should be held /fixed and just rotate with the crank arm and have a gap of about 1 or 2mm to the sensor.

 

[Newbie607]

Thanks. I will have a crack at making it fixed.....

 

[Deleted member 4366]

Like this but hidden behind your chain-wheel. Gap should be 1mm:

The disc should be tight enough on the shaft that it doesn't slip. If it does slip, you need a crank-puller to remove the chain-wheel ans then you can wrap something like thin plastic (not insulating tape) around the shaft to make it tighter.

 

[Newbie607]

Thanks so much for all the help. I just rotated it a bit and that has fixed the problem for now. Will get a proper fix done at the weekend. Happy pedalling!