Loud Currie Gear Reduction Motor

Scoot440

1 W
Joined
Nov 4, 2011
Messages
54
Location
Lubbock, TX
I just put together an ebike using a Currie-style 36V/450W gear reduction motor. I am very impressed with the motor's performance, but it screams like a banshee all the time. I remember reading a post a while back (maybe from Dark Angel) about repacking the gear lube in order to quieten the motor and increase the eficiency. Does anyone know where I can find that post or does anyone have any advice before I attempt this? Thanks in advance for any response.
 
Scoot440 said:
I just put together an ebike using a Currie-style 36V/450W gear reduction motor. I am very impressed with the motor's performance, but it screams like a banshee all the time. I remember reading a post a while back (maybe from Dark Angel) about repacking the gear lube in order to quieten the motor and increase the eficiency. Does anyone know where I can find that post or does anyone have any advice before I attempt this?.
One problem with internet messages is that it's difficult to convey audio volume. I don't have experience with that particular motor, but "screams like a banshee all the time" sure doesn't sound right. However, according to some posts, the older version of that motor does make a lot of noise. Is it a new motor or an old one?
I didn't sift through all those posts, but I question if you'll be able to dampen the Currie sound with lube. Dumbass said, "there's not anything you can do to reduce the noise I've spent a lot of time and monet trying."
Look on the positive side. You don't need to buy a horn.
 
Hi Nehmo - thanks for the reply and the links to the older thread. It looks like I will be living with the noise. The motor is a new one - I purchased it from TNC a few weeks ago. Until recently, I had a Currie E-zip with the same style of motor, but it was a 24V version and did not create anywhere near the noise that this motor does. I leave the house around 6am each morning and start a symphony of dogs barking all the way to work. On my way home in the evening, pedestrians notice me about 3/4 of a block away. It is definitely not a stealth bike, but it does occasionally remind me of riding an old two-stroke dirtbike. Definitely won't be needing a horn!
 
Using a higher voltage and/or at a greater wattage increases the sound from this motor, but at small loads its not so bad.
 
You can try adding additional grease. But I highly recommend you remove the old grease and use the thickest grease you can hind. I use a grease made by John Deare (sorry I don't remember which one). Keep in mind that the grease is going to expand when it get hot. So if you over pack it the extra grease is going to force int othe motor. You can also try loosing the greabox cap and realigning it(you'll have it off if you change the grease). It may not feel like it has much movement but in may be enough to quite the gears a little. But in the end there really isn't a lot you can do to quite the greabox noise other then building a sound proof box around it but then you have a venting problem.

I assume you have a true 36v motor and are not just over volting it which would really make it howl. You may also find the it improves as the gears wear in a little. I currently run twin 24v Currie motors on my bike and will be replacing them this winter with a 48v belt drive motor system to improve performance and noise. I would love to be able to make a new main gear for the Currie gearbox from plastic just to see if that would help.

Bob
 
I have some experience with this motor too. I have two 24V versions - one 250W and one 450W. Both are equally noisey.

The noise comes from a combimation of the straight cut metal gears and the motor's RPMs. I see some e-bikes with this motor exactly that seem to make less noise than mine. I think the reason is that they use a bigger sprocket on the motor, forcing it to turn slower (at the expence of efficiency and increased current).

If you really want to resolve this problem, the solution is helical gears. There is a swiss guy who sells kits with this motor and designed a helical gear solution. Check this link:

http://www.boosty.ch/en/boosty/boosty-motor.html

He charges something like $300 ( :shock: !?!) for the helical gears which is rediculus considering the motor is 50 bucks. Here is the like for that too:
http://www.boosty.ch/en/conversation-kits/motor.html?page=shop.product_details&flypage=flypage.tpl&product_id=207&category_id=17

Good luck
 
urialbocher said:
If you really want to resolve this problem, the solution is helical gears. There is a swiss guy who sells kits with this motor and designed a helical gear solution. Check this link:

http://www.boosty.ch/en/boosty/boosty-motor.html

He charges something like $300 ( :shock: !?!) for the helical gears which is rediculus considering the motor is 50 bucks. Here is the like for that too:
http://www.boosty.ch/en/conversation-kits/motor.html?page=shop.product_details&flypage=flypage.tpl&product_id=207&category_id=17

Good luck

One of us is confused........In both of your links they clearly say their units use a straight cut gear setup not helical and that they are noisy.

Did you post the wrong link?

Bob
 
You are confused :D

In the first link you need to read into text. Fourth paragpaph: ".... Now we have also developed a helical gear, extremely quiet gear. Experiments with different helical gears have shown that the efficiency is slightly worse and consume little more capacity, but much quieter."

and in the second link, use the drop down menu next to the "gear version" to see the cost for the helical version.

BTW, if it wasn't clear, I never bought these gears so I don't know how good it really is, but in general, I think it should work.
 
urialbocher said:
You are confused :D

BTW, if it wasn't clear, I never bought these gears so I don't know how good it really is, but in general, I think it should work.

Yes, you are correct. It was my confusion. :oops: A bit misleading the way they wrote the information. But still my falt for not reading (traslating) it better. As you say the cost is crazy.....no insane.

Bob
 
Thanks for all the responses. It is a true 36V motor and I will try replacing (but not overstuffing) the grease in the gearbox. Since I only have about $250 in the bike, I think I will hold off on the helical gears. :shock: It is fun to see the perplexed looks on people's faces as I approach, and it does help me to spread the word about e-bikes, so there are definitely worse things than having a whiny motor.
 
Scoot440 said:
Thanks for all the responses. It is a true 36V motor and I will try replacing (but not overstuffing) the grease in the gearbox. Since I only have about $250 in the bike, I think I will hold off on the helical gears. :shock: It is fun to see the perplexed looks on people's faces as I approach, and it does help me to spread the word about e-bikes, so there are definitely worse things than having a whiny motor.

The advantage is you won't scare the pants off them by sneeking up from behind. The disadvantage is some people don't feel ebike should be allowed on bike paths. So your giving your self away big time. I try to run the going speed on the trails and ease off the throttle when I pass people and I always say hello. It tends to take the edge off them if their an anti0ebike person.

Bob
 
I have a Currie Skyline. The motor is 250W and it's not really that noisy. I've also used the 450W version of the same motor and it was pretty quiet as well. They were both 24V motors. I'm also using a 16 tooth freewheel with it instead of the 20 tooth it comes with. Can the 24V motors be run at 36V?
 
lbz5mc12 said:
I have a Currie Skyline. The motor is 250W and it's not really that noisy. I've also used the 450W version of the same motor and it was pretty quiet as well. They were both 24V motors. I'm also using a 16 tooth freewheel with it instead of the 20 tooth it comes with. Can the 24V motors be run at 36V?

Yeah, not all the motors are noise makers. I had one that was very quite until I moved it from one bike to another. Then the noise started. I have to assume it was the alignment issue I spoke of ealier. I tried to get it quite again but never got as good as it was originally.

A lot of people have run the Currie 24v motors at 36v with very good luck. That being said however, there is always an added risk of failure. The trick is to not over do it with the throttle. Something that might also help is if you use a lower amp controller. In general voltage will add RPMs to a motor and amps will add torque. Again in general it's the amperage combind with the higher voltage that heats up the motor. So if your problem isn't a need for more torque it maybe best to consider a lower amperage 36v controller. Of course the motor spinning at higher speed will add wear but not like added heat will.

Bob
 
The trick now is to find a lower amp controller that's compatible with the motor. Can the sensor ed/sensor less controllers work with the Currie motors. I've noticed that the motor connection is green and blue so I was wondering if I hooked it up to the controller and just ignored the yellow wire would it work?
 
lbz5mc12 said:
The trick now is to find a lower amp controller that's compatible with the motor. Can the sensor ed/sensor less controllers work with the Currie motors. I've noticed that the motor connection is green and blue so I was wondering if I hooked it up to the controller and just ignored the yellow wire would it work?

First off let be sure we are talking bout the same type of Currie motor. Currie uses non-hub and hub motors on their bikes now. I am taking about the non-hub motors. These motors are low cost brushed motors and they only have 2 wires going to the controller. The colors are normally red and black. The wire color is not important but where did you get the third wire from? I've heard that some controllers will run on both brushed and brushless motors. But i have never tried it. It sounds like the controller you are talking about is for a brushless motor. You can find low cost brushed motor controllers everywhere for under $35. If I have time later I look at some suppliers. Bottom line be sure it's a brushed motor and buy a brushed motor controller to match it. A brushed motor controller will have only 2 motor wires. How you connect them to the motor will determine the direction of the motor rotation.

Bob
 
Yeah it's the side mounted motor. I went ahead and bought a 36V 500W controller from monsterscooterparts.com last night. It's a brushed motor controller. Oh and if anybody is having trouble finding the 16 tooth single speed left side freewheel for the Currie bikes, they sell them on amazon.com. I also ordered another one of those for my extra wheel. I figure I'll get everything by the middle of next week and I'll post an update.
 
There have been 2 types of external motors, used on the EZip-IZip.
The straight cut MY1080Z - Loud, more powerful
The helical geared XYD-16 - quiet, less power-speed
They do appear to look ... identical, have not compared closely.
Motor types

I clean the grease out and apply wheel bearing grease.
Just coat the gears teeth, then an extra marble sized gob, where the gears meet.
As an experiment, I also applied 2 balanced smears on the concave potion of the reduction gear.
My reasoning being ... If the gear were to overheat, lack of grease etc, the grease would slide outward hitting the drive gear - self lubricating.

If you remove the reduction gear, a "tension washer" might displace, make sure it is repositioned and lubed.
"Alignment" is performed by positioning the reduction gear cover, before tightening the cover screws.
Experimentation is necessary, tension towards tighter-looser gear meshing while tightening screws, try, then report!

Note: Any rear wheel work is greatly facilitated by doing the T-Plug mod. 100 amp T-Plug connector (Dean's Plug)
I was able to complete a spoke replacement in 11 minutes!
 
If you still have that list of suppliers I could use it. The controller I received doesn't seem to be compatible. I rearranged the wires on my throttle, and had the motor and battery plugged in but nothing happened. I bought a controller for a brushed motor, two wire connection for the motor.
 
lbz5mc12 said:
If you still have that list of suppliers I could use it. The controller I received doesn't seem to be compatible. I rearranged the wires on my throttle, and had the motor and battery plugged in but nothing happened. I bought a controller for a brushed motor, two wire connection for the motor.
Make sure "key"- possibly "lock" and "brake", maybe 2 "Brakes" are properly connected or shorted.
And proper voltage ... 36V?
 
lbz5mc12 said:
If you still have that list of suppliers I could use it. The controller I received doesn't seem to be compatible. I rearranged the wires on my throttle, and had the motor and battery plugged in but nothing happened. I bought a controller for a brushed motor, two wire connection for the motor.

If you have an install sheet or pic of hte wires it might help. If the controller has a "key" wire setup you need to install a jumper on it or it will not power up.

Bob
 
Well I need to read return policies better. I didn't realize that suppliers won't take controllers back. I'm stuck with the controller. However I found TNC scooters and they carry 36v Currie controllers and throttles and their prices are lower than Currie's.
 
lbz5mc12 said:
Well I need to read return policies better. I didn't realize that suppliers won't take controllers back. I'm stuck with the controller. However I found TNC scooters and they carry 36v Currie controllers and throttles and their prices are lower than Currie's.

Yeah, I've bought throttles and controllers (48v) from TNC last year. They pretest the units before they ship them (at least that's what they told me). But are you sure what you have is bad? I would think the no return policy is for an item that works not a defect.

Bob
 
Well I've given up on the idea of the 36V to the 24V motor. I went ahead and just mounted the parts I have on my GT Aggressor. I'm probably just going to try to sale it locally for $600.00. Other than the bike everything else is still pretty new. I did change out the drive freewheel for a 16 tooth. The battery's a 24V 15A lead acid from E-bikekit. I don't have the money to ship it anywhere. Unfortunately for me, I live in what I like to call "an EV dead zone" also known as San Bernardino, CA. It's probably because of the high crime and unemployment rate around here.
 
Back
Top