Hi there from Spain and UK

[orcecaveman]

Hi there and thanks for accepting me. Im about to collect a couple of cheapo folding bikes that ive bought. Oddly they both have the same problem in that the pedal assist doesnt work although there is power showing at the display (a basic LED 790)
So I apologise in advance, im going to be asking some cringeworthy, stupid, newby type questions....

 

[Nealh]

Welcome and ask away, that's what the site is for. No matter how trivial.
Usually pedal assist (PAS ) is relatively straight forward to fix.
When you get you bikes turn them upside down and have a look for a wired sensor and a magnetic disc attached/adjacent to the front chain rings, then post some pictures on the forum for help.

 

[flecc]

As Neale says.

Seago make the point of saying the rotation sensing on the current model has been integrated into the crank, so yours is probably external.
.

 

[orcecaveman]

Welcome and ask away, that's what the site is for. No matter how trivial.
Usually pedal assist (PAS ) is relatively straight forward to fix.
When you get you bikes turn them upside down and have a look for a wired sensor and a magnetic disc attached/adjacent to the front chain rings, then post some pictures on the forum for help.

Thank you for replying. I will do. I'm bring one at a time over to Spain on the bus! (I cant bring them on the plane due to the batteries). As you can tell by the pictures, theyve had little use and have been looked after. I think the previous owner lost interest because they stopped working. They both have the same problem, so I'm hoping it's something simple. Right now I'm busy reading previous posts to gain some knowledge.

 

[orcecaveman]

As Neale says.

Seago make the point of saying the rotation sensing on the current model has been integrated into the crank, so yours is probably external.
.

Interesting..... These are the earlier model, so maybe they identified a 'design fault'?

 

[flecc]

Interesting..... These are the earlier model, so maybe they identified a 'design fault'?

No, not a design fault, external rotation sensors are commonplace, but they have the disadvantage that mishandling can displace the sensor, preventing it reading correctly. That's very common.

If you post as Neale has said, we'll be able to check that for you.
.

 

[orcecaveman]

No, not a design fault, external rotation sensors are commonplace, but they have the disadvantage that mishandling can displace the sensor, preventing it reading correctly. That's very common.

If you post as Neale has said, we'll be able to check that for you.
.

I have been wondering (and hoping) that it may be that. What sort of clearance should there be between the sensor and rotor?

 

[flecc]

I have been wondering (and hoping) that it may be that. What sort of clearance should there be between the sensor and rotor?

As little as possible, just enough to allow the rotor to not touch the sensor. The rotor disc has a ring of small magnets and the Hall sensor needs to pick up each weak magnetic pulse as it passes. With rotation sensed by pedalling away, power is activated if the system is operational.
.

 

[orcecaveman]

As little as possible, just enough to allow the rotor to not touch the sensor. The rotor disc has a ring of small magnets and the Hall sensor needs to pick up each weak magnetic pulse as it passes. With rotation sensed by pedalling away, power is activated if the system is operational.
.

Cheers, I'll look at this before boarding the bus!

 

[Fat Rat]

Hi welcome to the site

Hope you get your bikes fixed soon

 

[orcecaveman]

Hi welcome to the site

Hope you get your bikes fixed soon

Thank you. I will keep you all updated as soon as I've got them home (this time next week)

 

[orcecaveman]

Thanks for the welcome!
My problem details now moved to here... https://www.pedelecs.co.uk/forum/threads/replace-upgrade-of-lcd-790-display-controller.34827/

 

[Nealh]

If the sensor Red led doesn't blink on and off as the magnets pass by then the wiring is faulty/wrong or the sensor may not be working and faulty.
Check the wire connectors and check the wire sequence is correct, If it helps take a pic of the connection and post it here.
Being China colours can vary quite a lot but generally Black is Gnd as can be Yellow, Red or Brown is 5V usually and then the remainig colour/s what ever they may be will be the signal wire.

 

[orcecaveman]

Replace / Upgrade of lcd 790 display & controller.

As my introduction thread started to get technical, I thought I best start a new thread. So, I've bought two Seago folding bikes in really good condition but both have the same issue: Batteries are fully charged, the display (LCD 790) lights up but there is no power assist. Obviously my first...

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