Recently purchased my first ebike. It's a Rambo Roamer and have been having a problem with the pedal assist. When using the pedal assist I keep using power. It seams totally random. Doesn't make any difference what gear, what PAS setting i use, and it happens at different speeds. I'm pedalling along and then the power from the motor just seems to quit then come back on again a few seconds to a few minutes later. The thumb throttle works without problem and I never loose power to the display. I have been emailing the company and they have been trying to help but it is really slow emailing back and forth so I thought I would ask for suggestion here in hopes of getting the issue resolved so I can get a chance to use the bike before the snow gets too deep. The company's 1st suggestion was to unplug the electric break sensors. I did that and it made no difference. Then they suggested it may be a problem with the PAS magnet. I took the motor apart and checked the magnet and it is not broke or cracked anywhere that I can see, but there may be a small crack in the plastic its really hard to tell. other than that the outside corners of the magnet look a bit ruff. Any thoughts?
Bafang BBS02 48V 750W mid-drive PAS Problem
- Thread starter Leigh_M
- Start date
AHicks
Well-Known Member
- Region
- USA
- City
- Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
My first thought was the brake sensors as well, but you've eliminated that. As you know, erratic stuff like this can be really tough to locate, because you can only trouble shoot when it's not working!
Is the display giving you any hint there's an issue? Connections at the motor are solid w/no corrosion? No pinched wires?
Is the display giving you any hint there's an issue? Connections at the motor are solid w/no corrosion? No pinched wires?
There is no indication on the display that there is a problem. everything is showing as it should. I checked the connections when I removed the motor everything was tight and there was no sign of pinched wires. Last I heard from the company was it's probably the hall sensor and I will need a new motor. They are all out of stock in US and asked me to check with the Rambo Canada to see if they have any in stock so I'm waiting to hear back from Rambo Canada. I have no idea what a "hall" sensor is.
AHicks
Well-Known Member
- Region
- USA
- City
- Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
The PAS hall sensor is the one the magnets are passing by. Usually 3 tiny wires going to it. Positive, negative, and the sensor lead. It senses and sends a pulse of electricity every time a magnet goes by it. Controller looks for that pulse, and unless one or both of the brakes are on, turns the power to the motor on when it sees it.
That signal from the PAS sensor, along with the fact neither brake switch is on, are about all there is to the PAS circuit. Nothing else should be affecting it. Point being, if those are all OK, with no dirty connections or broken wires, it SHOULD work.
If I were sitting around with nothing to do, but in a hurry to get this bike going, I would confirm the sensor is getting power, the ground wire was actually grounded, and maybe the sensor wire is getting power when the crank is turned. It's all low voltage, just under 6v.
tomjasz
Well-Known Member
- Region
- USA
- City
- Minnesnowta
Do use a continuity setting on your multimeter to confirm the brake switch is working.
Is this a newer motor? 2016 or later? BBS02B
How old is the battery? Motor mileage? Battery fully charged? Tested?
I'm suspecting battery sag. What is the voltage/watts on the display when it cuts out?
This may be the best forum troubleshooting guide.
Is this a newer motor? 2016 or later? BBS02B
How old is the battery? Motor mileage? Battery fully charged? Tested?
I'm suspecting battery sag. What is the voltage/watts on the display when it cuts out?
This may be the best forum troubleshooting guide.
Mauclair12
New Member
- Region
- Canada
i have a related issue, my speed se sent is working But : the pedal assist Does not engage.
- Trhottle is working fine
- brake sensors are not installed -wich was working fine on initial
- i ve got a new controller that i had to buy from chinese supplier and sent me a new one after only 800 km 4 months of use.
- A solid red light is getting on on the seed sensor at the rear ( BBS02 ) of my bike
Any Idea where I should look ?
- seller is not helping much just asking for a video of the situation …
tomjasz
Well-Known Member
- Region
- USA
- City
- Minnesnowta
Sensor should blink when the magnet passes. Not always lit.
If you pure contrpoller has failed it may be user error. BBS02 motors overheat when the motor is lugged. Typically I’ve seen controllers fair when riders take off from a dead stop with their throttle and not shifting as we would sand motor. Is the motor labeled BBS02B? If yes then it has improved FET’s. Based on my watching parts orders controllers have had far less failed with BBS02B
If you pure contrpoller has failed it may be user error. BBS02 motors overheat when the motor is lugged. Typically I’ve seen controllers fair when riders take off from a dead stop with their throttle and not shifting as we would sand motor. Is the motor labeled BBS02B? If yes then it has improved FET’s. Based on my watching parts orders controllers have had far less failed with BBS02B
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