Noise from rear hub when going 21mph+

[FozZ]

Had same problem,

I have a step-thru 2.0 and an XP 2.0. On my XP when going approximately 21-22mph and over (although only goes to 24mph) I get a grinding sound coming from the rear hub. This is on a flat surface, with no headwind. I weight about 165 lbs. I made a video and posted it on YouTube. I sent the link to tech support but they suggested it might be a loose fender. The sound immediately stops when letting off the throttle, so I really don't think it's the fender. I could swap controllers, but I'm saving that as a last resort. Here's a link to the video. The sound start at about the :17 sec mark:

Heard the same fender suggestion. Sent them a recording. My free warranty replacement wheel is arriving today. Thanks Lectric!

 

[RJB58]

Just got my 2.0 a few days ago and have a similar problem with a different trigger. My grinding sound occurs when I go into PAS 3. When I stop pedaling the noise disappears. I also noticed that PAS 3 did not always engage right away but took several seconds before it kicked in. That was a more random occurrence. I will be reaching out to Lectric in the morning.

 

[RJB58]

I inserted rubber washers everywhere I could reach an attachment point for the rear fender and took it for a test ride. When I put it in PAS 3 I did hear the grinding sound but it occurred randomly rather than continuously. There is definitely something going on that is vibration-induced when the motor is working hard. I just can’t figure out yet whether It is inside the motor (and to what extent) versus resonances elsewhere. I know I will need to remove the fender to get to the bottom of things but I don’t have the tools to reach all the screws without removing the wheel and I’m not looking forward to doing that.

 

[FatChance]

Have you adjusted the rear derailleur? Is the rear derailleur protection cage bent so it does not affect the free movement of the derailleur?

 

[RJB58]

I adjusted the derailleur when I set up the bike. The cage is not bent.

 

[tomjasz]

Lesson here, $1000 bikes. I bought a quality motor, dealer price, strung in a wheel and battery for over $1000.
i know it’s frustrating and I feel your pain, but that fact remains...

 

[RJB58]

I found a local ebike shop that has agreed to do a thorough wellness check on my XP 2.0. We’ll see what comes of it.

 

[Dorkyman]

Okay, I've tried to hear what you're talking about, and at top speed all I hear is the high pitch of the motor gearset--and a rapid clicking, which is about the speed of the rotating wheel. My assumption at this point is that the brake rotor is touching the pad. Is this clicking the noise everyone hears?

 

[FatTireFan]

Lesson here, $1000 bikes. I bought a quality motor, dealer price, strung in a wheel and battery for over $1000.
i know it’s frustrating and I feel your pain, but that fact remains...

Seems to be a small amount of complaints for the amount of bikes sold by Lectric, and most seem to be shipping issues which the company addresses along with the mechanical ones. I’ve put over 4K miles on my two (original and Lite) and the only issue I had was my original got delayed two weeks because the veterans discount was put in after my purchase (paperwork snafu).

 

[tomjasz]

Seems to be a small amount of complaints for the amount of bikes sold by Lectric,

Well, there are a few in the local community and I've had 4 riders already hunt me down to work on their bikes. I'm thrilled to read you have 4000 miles on yours. People do occasionally win in Lost Wages too...
Time will tell how these bikes pan out and how many make 4000 miles. I wish claims were backed with odometer photos...
Again, I'm happy to read about your success. In the end being happy with our ride is the most important feature.

 

[Dorkyman]

I don't doubt your experience but what is it that goes wrong with the bikes you've worked on? It's just a generic 7-speed bicycle, like a hundred million others. Nothing exotic so a bit heavier than, say, carbon fiber, but on our two Step-through bikes the brakes and shifter work flawlessly. Wheels, suspension, frame, rack all seem rugged. Don't know about the electrical system, but Lectric claims excellent water resistance and so far our two bikes are performing 10/10.

 

[RJB58]

Finally got around to recording the sound and sending it to Lectric. Within two hours I got a reply email and they agreed something wasn’t right and a replacement part is on the way. I hope they send me a full rear wheel assembly and not just a new hub motor.

 

[tomjasz]

Finally got around to recording the sound and sending it to Lectric. Within two hours they agreed something wasn’t right and a replacement part is on the way. I hope they send me a full rear wheel assembly and not just a new hub motor.

Keep us in the loop. Thanks

 

[RJB58]

Could someone please explain why it might be a controller problem? I guess I don’t understand how they work.

 

[tomjasz]

Could someone please explain why it might be a controller problem? I guess I don’t understand how they work.

See what lectric comes up with. Controllers can have electrical issues and the hall sensors get out of whack making crazy noises. But Lectric probably has a pattern of common failures and have a better idea as to what’s up. The easiest way to explain is it could be a timing issue.

 

[tomjasz]

What is the use of the hall sensor in the ebike?​

As it is known that the motor of the electric bike works by using electromagnetic energy, and the function of the hall sensors is to send data about the amount of electromagnetic energy to the controller.

the controller uses these readings and translates them into commands that are sent to the battery, the motor, and the rest of the parts of the electric bike.

What Happens If Ebike Hall sensor fails?​

Although the hall sensors are located inside the motor, which is not visible, there are signs that can be used to know if the hall sensors have a problem or not.


As a general rule, when the hall sensors fail the motor stopped working and starts to vibrate for a few seconds, also
a whining sound is heard, or in some cases, a continuous loud noise comes out of the motor.

​

 

[Dorkyman]

I note on my st that there is a "buzzing" coming from the rear at around 11mph (calibrated, not stock LCD setting). To me it sounds exactly like sympathetic vibrations in the rear fender at a particular frequency. Should be easy to verify by just stuffing a rag or towel in-between the fender and the rack. We'll see.

 

[Dorkyman]

FOUND IT.

A few minutes ago I found an old car-washing sponge (bigger than a kitchen sponge) and folded it in half and jammed it into the small space between the top of the rear fender and the luggage rack an inch or so above it. Noise is now gone!

So in my case, at least, I think at about 11mph (GPS calibrated, not stock) the frequency of the hub motor and/or reduction gears induced a very loud sympathetic metallic vibration in the rear fender. I guess I can next try to mount the fender with rubber washers but for now an inconspicuous old sponge makes the bike totally free of buzzes no matter the motor speed.

 

[RJB58]

I am glad that worked for you. I had already put rubber washers at every metal to metal attachment point for the rear fender except where there is limited space to reach the screw between the tire and the fender. I still get an occasional short-lived rattle sound that could well be a resonance. Lectric is sending me a new rear wheel assembly so I’m hoping that takes care of the other noises and issues I’m having that I think are hub motor related.

 

[RJB58]

Got the new wheel delivered a couple of hours ago. Will try to get it installed this evening.