Power reduction while pedaling

[LowLow]

Hi. I have a ‘21 Giant e-Trance, which has been great. However, I noticed that recently while pedaling the power seems to shut off or reduce for a split second and then come back. It only does it occasionally and I’m hoping it’ll magically go away. I’m not too worried about it if it doesn’t get worse. I was just curious if this was a known issue.

Also, anyone else have cracking/crackling sounds coming from their bike? Pivots too tight? BB/crank interface?

Love the bike by the way! I’m 5’9” and on a medium. I wish there was a bit more reach but otherwise it’s great. The weight doesn’t bother me, and I actually like the loooong chain stays. Not sure if I’d get another one like that but it’s pretty fun to try something that stands out from other bikes and man you can get some speed on it. It can handle so much. This is my first ebike so maybe they’re all like this, but so forgiving. A real plow machine, which is also a nice change of pace.

Thanks!

 

[Herder000]

That doesn’t sound right Never had split second power shut off/reduce or creaking/crackling on my 2019 Trance. i‘d take it back to the shop if possible. I have had intermittent battery cut outs before and had to use an electrical cleaner on the contacts but then the whole bike switched off completely. Maybe make sure the battery is secured I properly and there is no play in it, there is a small chance it could be poor contacts I guess. Sorry can’t be more helpful than that.

 

[DrStupid]

Hi. I have a ‘21 Giant e-Trance, which has been great. However, I noticed that recently while pedaling the power seems to shut off or reduce for a split second and then come back. It only does it occasionally and I’m hoping it’ll magically go away. I’m not too worried about it if it doesn’t get worse. I was just curious if this was a known issue.

Also, anyone else have cracking/crackling sounds coming from their bike? Pivots too tight? BB/crank interface?

Love the bike by the way! I’m 5’9” and on a medium. I wish there was a bit more reach but otherwise it’s great. The weight doesn’t bother me, and I actually like the loooong chain stays. Not sure if I’d get another one like that but it’s pretty fun to try something that stands out from other bikes and man you can get some speed on it. It can handle so much. This is my first ebike so maybe they’re all like this, but so forgiving. A real plow machine, which is also a nice change of pace.

Thanks!

Missing a power beat:
Is yours a Trance X?
It sounds like the speed sensor didn't pickup the wheel magnet for one revolution.

Creeps:
As for creeps, there is plenty of good information about a few common creeps, that can be hard to find.
The motor mount bolts, if I remember correct can be a bitsch. The post are somewhere around here, some are pretty old.

 

[LowLow]

Missing a power beat:
Is yours a Trance X?
It sounds like the speed sensor didn't pickup the wheel magnet for one revolution.

Creeps:
As for creeps, there is plenty of good information about a few common creeps, that can be hard to find.
The motor mount bolts, if I remember correct can be a bitsch. The post are somewhere around here, some are pretty old.

Thanks for the info. Yup, mine is the Trance X E+ Pro 29 1. I'll check to see if there's something maybe blocking the sensor. Thanks again!

 

[DrStupid]

Thanks for the info. Yup, mine is the Trance X E+ Pro 29 1. I'll check to see if there's something maybe blocking the sensor. Thanks again!

Could be anything unfortunately, but my 19 trance does this frequently, when the magnet is not adjusted just so, on the spoke.

Yours don't have the spoke trouble, but it's worth a look forsure. Easy enough.?good luck

 

[Ozscottino]

Could be anything unfortunately, but my 19 trance does this frequently, when the magnet is not adjusted just so, on the spoke.

Yours don't have the spoke trouble, but it's worth a look forsure. Easy enough.?good luck

Thanks for sharing this.

I too have an 19. Did you find anything else that helped? Or just purely magnet placement? I wonder if a larger magnet would help?

 

[DrStupid]

Thanks for sharing this.

I too have an 19. Did you find anything else that helped? Or just purely magnet placement? I wonder if a larger magnet would help?

Two things actually, both almost completely useless bits of information.

Two magnets, on concurrent spokes, a trick used by some as a fail safe, does not work with our Giants. The double pulse confuses the controller. Now?... two magnets on one spoke, that might actually help, at least as fail safe for losing a magnet! Your idea about a larger magnet triggered this thought.

Giant has a somewhat unique approach to output power, not often mentioned, that could also be contributing to the power pulses we feel. Even with a perfectly aligned magnet, there are moments on both my giants (2019&2021), when power drops significantly for a few 100ths of a second, and then resumes normally. Read below and see what you think?

Giant SyncDrive E-Bike Motor Technology | Giant Bicycles US

SyncDrive Technology provides pedaling assistance that’s synchronized with human input. It produces smooth pedaling power with a natural feel that is sonically tuned for quiet performance.

www.giant-bicycles.com

 

[Ozscottino]

Thank you for that information.

This morning I adjusted the magnet placement again.

And also tried a larger magnet. No change

I do like the idea of having a spare magnet.

I have ended up taking the bike back and see what they come up with... As I am stuck.


In relation to the giant info you shared. The pause is definitely longer than a second.. wonder if controller fault.. ?

Two things actually, both almost completely useless bits of information.

Two magnets, on concurrent spokes, a trick used by some as a fail safe, does not work with our Giants. The double pulse confuses the controller. Now?... two magnets on one spoke, that might actually help, at least as fail safe for losing a magnet! Your idea about a larger magnet triggered this thought.

Giant has a somewhat unique approach to output power, not often mentioned, that could also be contributing to the power pulses we feel. Even with a perfectly aligned magnet, there are moments on both my giants (2019&2021), when power drops significantly for a few 100ths of a second, and then resumes normally. Read below and see what you think?


View attachment 58248

Giant SyncDrive E-Bike Motor Technology | Giant Bicycles US

SyncDrive Technology provides pedaling assistance that’s synchronized with human input. It produces smooth pedaling power with a natural feel that is sonically tuned for quiet performance.

www.giant-bicycles.com

 

[DrStupid]

Thank you for that information.

This morning I adjusted the magnet placement again.

And also tried a larger magnet. No change

I do like the idea of having a spare magnet.

I have ended up taking the bike back and see what they come up with... As I am stuck.


In relation to the giant info you shared. The pause is definitely longer than a second.. wonder if controller fault.. ?

Sorry to here it. Was yours powering off or posting a fault?

Based on what I experienced, when experimenting with two magnets on consecutive spokes, I know that if the magnetic pulse is broken in two, the motor will suspend support for what seems like an entire rotation of the wheel, then surge and repeat. It was immediately unbearable, and I removed the second magnet after one trip down the drive.

I'm speculating a bad speed sensor assembly, failing intermittently, would break up the pulse. But, unfortunately so would a bad motor controller board interpreting the signal. ?