I have a FLX roadster It has a Bafang 500w motor and with a 36v battery and throttle. I'll be pedaling along, no throttle just PAS and all of a sudden the power will quite and then pop back on My wife describe it has like some was pumping their gas pedal. Does anyone have a clue about what might be causing the problem we have 2 bikes and the problem is appearing on both of them. I was thinking a torque sensor Any one have a clue Thanks
motor cuts out at times
- Thread starter Stu
- Start date
TMH
Well-Known Member
Does it do this with a full battery, or only when the battery level is low? Have you cleaned the battery and battery socket contacts? Are the batteries a little loose or do they rattle? Have you used dielectric grease on the contacts?
I've also got a Roadster which, although it doesn't have many miles and doesn't get ridden in the rain, does not exhibit this characteristic. I do not have the throttle.
When I first got the bike I would have some issues with the display going blank, and total motor cut-off. I sprayed some contact cleaner into the plugs/sockets going into the display and haven't had recurrence of this issue lately.
Do you get the same "pumping the gas pedal" if using the throttle only? Might point more to the torque sensor if it doesn't happen with throttle only.
I had a similar issue with a Bosch mid-drive, but it only seemed to happen when the battery was 2-3 bars or lower. Cleaned everything up, but still happened some. Battery didn't seem overly loose, but I put a short (4") piece of self-adhesive weatherstrip foam under the battery and the issue has never happened again.
I've also got a Roadster which, although it doesn't have many miles and doesn't get ridden in the rain, does not exhibit this characteristic. I do not have the throttle.
When I first got the bike I would have some issues with the display going blank, and total motor cut-off. I sprayed some contact cleaner into the plugs/sockets going into the display and haven't had recurrence of this issue lately.
Do you get the same "pumping the gas pedal" if using the throttle only? Might point more to the torque sensor if it doesn't happen with throttle only.
I had a similar issue with a Bosch mid-drive, but it only seemed to happen when the battery was 2-3 bars or lower. Cleaned everything up, but still happened some. Battery didn't seem overly loose, but I put a short (4") piece of self-adhesive weatherstrip foam under the battery and the issue has never happened again.
TMH
Well-Known Member
Good thought. I had read the op as this was something new and different which was happening. But maybe not.
TMH
Well-Known Member
1)Turn on the bike like normal.
2) Press and hold both up and down arrow keys
3) When you get the next screen arrow down to 'Information'
4) When you get to the Information screen, I think the second line down is Speed Limit. Arrow down to it and hit the mode button
5) Mine is set at 32. Don't know whether this is mph since I'm in imperial units
6) If yours is not set at 32 (the max) change it with arrow keys
7) Press and hold both up and down arrow keys to return to main (riding) display screen
8) Let us know what you found and if it helps!
I took it to the shop actually 2 bikes and neither of them acted up so in there mind there was no problem. WRONG At this point I will take it back and probably rideover about 6 miles because it cuts out more often when the engine is warmed up. The other day after putting about 6 mi on it and then letting it sit for a couple of hours the PAS didn't work at all on the ride home but the throttle worked. Yesterday I rode about 10 mi and all things worked as designed. I am leaning toward a PAS problem. I don't really know how a torque sensor works but I think that is where the problem lies.
ian fisher
Member
have a look at how the battery is locked into the frame, with the battery in place, can you move it at all? the slightest disconnection is enough to cause a spark between the contacts and this will result in a power loss.
eightyeightkeys
New Member
Stu, I'm having the same problem all of a sudden. Was it solved ? What was the fix ?
My EBike pauses briefly every 11-12 rotations of the pedal.
My EBike pauses briefly every 11-12 rotations of the pedal.
Merle Nelson
Well-Known Member
- Region
- USA
Look at the date of Stu's last post in this thread 88. You could be waiting a while for an answer.
If you didn't know you can click on his name and go to his profile area. Click on his name again, then click on "postings" and see when his last activity was. If he is still posting here put @ before his name in a post and he'll get a notification.
I got a result a little akin to his original post when I was first riding my ebike. Turns out I was drapping my hands over the brakes with a little too much weight and getting brake motor cutout to working here and there.
If you didn't know you can click on his name and go to his profile area. Click on his name again, then click on "postings" and see when his last activity was. If he is still posting here put @ before his name in a post and he'll get a notification.
I got a result a little akin to his original post when I was first riding my ebike. Turns out I was drapping my hands over the brakes with a little too much weight and getting brake motor cutout to working here and there.
eightyeightkeys
New Member
O.K. Thanks Merle.
It's not my hands, but, I'll look at the disc brakes at little closer.
What is very strange is that it's "regular." Every 12 rotations of the pedal the motor cuts-out or pauses very briefly.
It's not my hands, but, I'll look at the disc brakes at little closer.
What is very strange is that it's "regular." Every 12 rotations of the pedal the motor cuts-out or pauses very briefly.
Merle Nelson
Well-Known Member
- Region
- USA
No....I was just yammering by that point. That doesn't sound like your issue at all.
Someone will have some real ideas.
Someone will have some real ideas.
PedalUma
Well-Known Member
- Region
- USA
- City
- Petaluma, CA
It sounds like it is somehow out of phase which is weird and would not know how to fix.
A guy had a similar problem two days ago and brought me his bike. I was thinking from the way he described the problem on the phone that it could be his torque sensor, cadence sensor, or controller $$$. It turns out that the wheel magnet (located on a rear spoke) was twisted by 45 degrees. The in-person diagnosis and repair took ten-seconds. He was super happy. I did not charge him.
Funny side story: A guy had a bucking bike. It was a hub-drive with PAS magnets. Some of the magnets were in reverse polarity. If you want to play a trick on someone reverse some of their PAS magnets.
I have the same pumping the gas accelerator pedal effect. I have Bafang front hub drive and rear mounted battery. Climbing a hill there are the power no power, but on flats it’s fine. Another post mentioned could be loose battery connection since the hill is full of potholes and road surface irregularities that’s causing rattles. I’ll report back my findings.
PedalUma
Well-Known Member
- Region
- USA
- City
- Petaluma, CA
Definitely look at the battery connections.
Among the things to also check such as the wheel magnet alignment and 2mm distance from the pickup, check that the PAS pickup at the crank is about the thickness of a nickel from the magnetic wheel. If the wheel magnet & speed sensor are too far apart sometimes I will stack a second magnet on the first, that is if moving them closer is not practical. Spokes are flexing on bumpy stuff. Check that they are evenly tight because that gap distance to the pickup could be flexing causing a temporary cutout. I hope this helps.
eightyeightkeys
New Member
Bingo ! We have a winner.
Ha !!!! When Biktrix sent me back my rear wheel with a new 8 speed hub they forgot the speed sensor magnet and I never even noticed.
This causes the E Bike to behave strangely with a pause every 12 rotations of the pedals and all the PAS levels are slightly berserk.
Similar threads
