Help! No Power Assist middrive motor

rob200375

Finding my (electric) wheels
May 4, 2020
5
0
Hi

I have a Pro Rider Surge Electric Mountain Bike Mens e Bike 250W dapu middrive 36V 18 Electric Bicycle with a power assist issue - I've read around and double-checked the suggestions and I still cannot get the power assist to engage when I am pedaling, all signs point to it not having an issue all cables are connected all lights are on as expected and the battery is fully charged, but nothing happens.

the bike is about 3 months out of warranty and the supplier does not want to assist?

Any ideas - does anyone have same bike or know how to fix -

the bike has probably only done 500 miles at most and is gathering dust - so I thought I would see if anyone can assist while in lockdown, I phone my local bike shop and they dont deal with this model motor and suggested I reach out on a forum and see what they have to say on it


thanks in advance

Rob.
 

RoadieRoger

Esteemed Pedelecer
Nov 8, 2010
726
200
Rob your problem could be caused by an excessive gap between the wheel sensor and the pick up . I have a Pro Rider Flare and lost the drive because of this . The gap to get the power back is scarily small ,almost verging on rubbing . If you set the gap to the usual as per most other machines you won`t have any drive .
 
  • Like
Reactions: artspeck

rob200375

Finding my (electric) wheels
May 4, 2020
5
0
Rob your problem could be caused by an excessive gap between the wheel sensor and the pick up . I have a Pro Rider Flare and lost the drive because of this . The gap to get the power back is scarily small ,almost verging on rubbing . If you set the gap to the usual as per most other machines you won`t have any drive .
Thanks for the suggestion where abouts do I see or find this sensor
I have a sensor in the wheel which lines to a receiver on the frame is this the one on the rear wheel it has a 5mm gap approx
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
20,917
8,533
61
West Sx RH
It's a mid drive not a hub drive the PAS sensor is internal.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
20,917
8,533
61
West Sx RH
A brake sensor if fitted can cause the issue, if it the lever doesn't return fully the sensor may not be closed.
 

Andy-Mat

Esteemed Pedelecer
Oct 26, 2018
2,214
562
78
Check with a meter that the battery is not in fail safe, that is close to or below 30 volts, though its probably a brake sensor.....as someone has already mentioned, if the battery charge level is correct.
Andy
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
20,917
8,533
61
West Sx RH
If the LED or LCD lights up then you know the fuse is intact, as Andy has mentioned do check battery SOC with a meter for a definite voltage read out.
 

RoadieRoger

Esteemed Pedelecer
Nov 8, 2010
726
200
The sensor is on a rear wheel spoke and the pick-up is on the horizontal rear frame . Mine is the Dapu Mid motor as well. I found this quirk when experimenting with positioning of the sensor at various spoke positions . I have three Ebikes , two with hub drives and this one . Give me a hub drive any day , as I find the act of gear changing on the mid motor loses momentum when the drive is momentarily cut by the gear sensor mechanism . The whole riding experience does not seem so natural as the hub one .
 

rob200375

Finding my (electric) wheels
May 4, 2020
5
0
thanks for the info - i will check this as soon as it stops raining :)

the sensor on the wheel is a fair distance from the horizontal frame - i will check that

Ill also get hold of a meter and check the voltage - the button press shows full battery
 

Andy-Mat

Esteemed Pedelecer
Oct 26, 2018
2,214
562
78
not sure - if it has - how do i tell
Wiring going to the brake levers on the handlebars.
Mine has two, one for each brake, but apparently some bikes have only one brake wired (I have never seen that), as for proper braking you must use both brakes together....Logical.
Andy