RX (2021) Motor Hum?

SpartyOn11

Member
Region
USA
Started noticing a weird noise coming from the motor of my Rize RX (2021). If you click on the video below, it will open imgur and you will see 2 videos. Listen for the noise behind the normal motor hum. There is like a "rubbing" or other type of noise that only happens when pedaling. At first I thought a brake was rubbing but it doesnt happen when coasting.

 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
All I hear is wind noise in the first one, and the typical motor (gear) noise in the second.

Gear noise is totally typical for the Ultra's, and the only time you're going to hear it is when the motor is running. When you stop pedaling the motor stops, so the noise will too. This issue is well documented. Somebody, I forget who, is supposed to be introducing a composite gear to replace the metal gear making the racket. That announcement was made this past summer, but I haven't seen any more on it. This gear, and the time/trouble to replace it, will be available on your dime as it's considered an accessory.

I have about a thousand miles on mine, and it does seem that it's not quite as noisy as when I first got it, but I may just be getting used to it as well. Noise is definetly more apparent while accelerating and at higher speeds. When on a quiet single track doing 6mph for instance, you barely hear it. -Al
 
Last edited:

SpartyOn11

Member
Region
USA
@AHicks Sorry for the wind noise in the video. I tried to get another one this weekend and that is in the link below. I think this new video shows the noise a lot louder. In the first part of the video I only hear the "rubbing" noise but then as you can see I stop pedaling and then start again. The normal motor hum comes in but then that "rubbing" noise. We bought two of the same bikes and my wife's bike does not make this noise. It is really really loud and quite annoying.

 

Bubba zanetti

Well-Known Member
Region
Canada
City
Trail, BC
That is a very peculiar sound. I would not be riding till that is narrowed down. Did you send this to Rize?
 

SpartyOn11

Member
Region
USA
That is a very peculiar sound. I would not be riding till that is narrowed down. Did you send this to Rize?
I did but i guess i didnt follow their specific format for emailing so I just sent that back to them in the correct format. Some people have said this is normal but I dont think so. There is no way a motor can be that loud. I feel like it is so loud I cannot even hear my phone playing music on the handlebars sometimes. I get their should be a hum but not this alien like shrieking
 

Bubba zanetti

Well-Known Member
Region
Canada
City
Trail, BC
I did but i guess i didnt follow their specific format for emailing so I just sent that back to them in the correct format. Some people have said this is normal but I dont think so. There is no way a motor can be that loud. I feel like it is so loud I cannot even hear my phone playing music on the handlebars sometimes. I get their should be a hum but not this alien like shrieking
Loud and the pitch sounds completely different. I can hear the typical motor sound, then the higher pitch kicks in. Clutch binding? It sounds metallic to me.
I’m sure you have checked tightness of crank arm bolts etc.
Best of luck, I’m sure it will be resolved just damn inconvenience
 

SpartyOn11

Member
Region
USA
Loud and the pitch sounds completely different. I can hear the typical motor sound, then the higher pitch kicks in. Clutch binding? It sounds metallic to me.
I’m sure you have checked tightness of crank arm bolts etc.
Best of luck, I’m sure it will be resolved just damn inconvenience
Yup, checked all bolts upon assembly. Thanks. It really gets peoples attention that is for sure lol
 

GoinGrey

Member
Yup, checked all bolts upon assembly. Thanks. It really gets peoples attention that is for sure lol
That noise is not normal and anyone telling you that has lost their mind. Sounds to me that the motor and controller are singing into the frame. I'm curious if you know what brand of controller you have?
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
That noise is not normal and anyone telling you that has lost their mind. Sounds to me that the motor and controller are singing into the frame. I'm curious if you know what brand of controller you have?
Ultra motors have an internal controller......by Bafang.
 

SpartyOn11

Member
Region
USA
@Bubba zanetti @HoustonGlen I did get a response from Rize after following their reporting an issue template. They asked me to take two more videos; one in walk mode and one with throttle only. I just sent those off on Monday. I have noticed the consistency of when this happens is erratic. Meaning, sometimes it happens within the first mile or two and sometimes it takes 5+ miles for it to occur. To get the throttle video, I had to ride over 5 miles before the noise started. The consistency is that it definitely happens every ride if that ride is 5+ miles long. Waiting on a reply from Rize
 

SpartyOn11

Member
Region
USA
So it makes the same noise under throttle with know pedalling?
After it starts making that noise through pedaling it will also make the noise with throttle. I also noticed it started with throttle after you brake hard. For example, I brake hard (not tire screeching hard) to a slower speed then use throttle the sound would happen. Not as loud but it happened.
 

SpartyOn11

Member
Region
USA
@Bubba zanetti @AHicks @HoustonGlen So Rize got back to me and had me send them a photo of the bottom of the motor where the part number and details are. They sent me a replacement motor that I received today. Unfortunately, they sent me a 48v 30A motor with part number MM G510.1000 12. The motor off the bike is a 52V 28A motor with part number MM G510.1000C 12. I wonder why they did this. I just emailed them telling them the mistake. What would happen if I put the 48V motor in the bike? Are there pros & cons for using the 48V motor vs the 52V motor?
 

Bubba zanetti

Well-Known Member
Region
Canada
City
Trail, BC
@Bubba zanetti @AHicks @HoustonGlen So Rize got back to me and had me send them a photo of the bottom of the motor where the part number and details are. They sent me a replacement motor that I received today. Unfortunately, they sent me a 48v 30A motor with part number MM G510.1000 12. The motor off the bike is a 52V 28A motor with part number MM G510.1000C 12. I wonder why they did this. I just emailed them telling them the mistake. What would happen if I put the 48V motor in the bike? Are there pros & cons for using the 48V motor vs the 52V motor?
What is your battery voltage and amps? I’m assuming 52 volts as well?
 

Bubba zanetti

Well-Known Member
Region
Canada
City
Trail, BC
I actually think it should be fine. One benefit is you may have received a non canbus motor, which be highly and easily tuned.
 

SpartyOn11

Member
Region
USA
@Bubba zanetti I believe it is a 52V battery. If I am not mistaken, Rize switched this model to a 52V for the new models. Last year's model I believe was a 48V system. What do you mean by non-canbus?
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
Last year's motors are known as UART based motors, and the controllers are easily programmed to "customize" them to a rider's preferences. A HUGE attribute many riders enjoy. This year, Bafang has done everything they can to eliminate this feature (for now anyway) by changing to what is known as a CANBUS controller interface. These are NOT able to be programmed - yet. The brainiacs are still working on breaking the code to allow us common folk the ability to do what we can now with the UART motors.

My thought is that if you received a UART based motor, and your bike is currently set up for CANBUS, they're going to need to send you a UART main harness (easy swap, don't panic), as well as a display that works with the UART as the CANBUS display will not.

UART vs CANBUS displays are easy to tell apart, will give you a hint as to what's going on with the bike you have. Where the display lead plugs in to the main harness, the UART based stuff will use a round green connector. If its a CAN BUS based bike, it will have what has been called a "house" shaped connector - NOT the round green one.

Bottom line, before things get much further, and you spend some "quality time" communicating with the factory, I would have a look at your display connector to identify that as UART or CANBUS, then carefully compare the connectors on the motor you have and the motor you received to see if they match.

Best of luck! -Al
 

Bubba zanetti

Well-Known Member
Region
Canada
City
Trail, BC
The UART CONNECT IS ROUND


This is a CANBUS connector
 

Attachments

  • 72648CFD-013B-435A-9586-0E5EE04CEA19.png
    72648CFD-013B-435A-9586-0E5EE04CEA19.png
    64.5 KB · Views: 87

SpartyOn11

Member
Region
USA
Well, the motor cannot be used anyway because there are two connectors that are different on the 48V motor than the 52V motor I removed. I have contacted RIZE again and they are working to get me another replacement. We will see what happens.