Hub motor noise

[ZeroEm]

That is great. bearings are a cheap fix. Details, details must pay attention to details.

 

[Eastwood]

That is great. bearings are a cheap fix. Details, details must pay attention to details.

Yes the bearings were a cheap fix Glad to have it fixed and working properly. Now no more hard impacts on that rear wheel! :lol:
The root cause of this issue are two separate hard impacts. The first one as I mentioned I flipped the bike over at a very slow speed doing an Endo, don’t ask me how that happened it was an unintentional Endo lol. The second hard impact was when a construction truck was backing out of a driveway in a neighborhood and had to swerve off the road and the back wheel struck a huge ledge of a driveway which busted the halo rim lol that driveway was sticking up about 4 inches of a 90° angle, concrete!

 

[raylo32]

8 ga phase wires? Jaysus, Mary and Josephine! That should do it.

 

[Eastwood]

8 ga phase wires?

I know right :lol:

With the testing I did yesterday the phase wires don’t even get warm at all, even at 150 phase amps! Obviously the wires are a bit overkill :lol: but it helps with efficiency. Have way less voltage drop now. But that’s also contributed to the upgraded battery wires as well.

Going to do some more testing today, will take it on some mountain bike trails and I’m curious to see what the motor temperature Peaks at. I have some trails near my house and they have some massive steep hills. It’ll be a good test to see the motor temps. Plus it’s about 90° today

Edit:200 phase amps not 150 phase amps
I ran 150 for the longest but the last several months I turned it up to 200 phase amps.

 

[Eastwood]

Well the hub motor performed great again today, still no clicking noise

pushed the motor really hard today with a lot of stop and go full throttle dumps
I didn’t monitor the temperature to closely but I think the peak was around 100°F. I got distracted with having fun lol also forgot to monitor the voltage drop as I don’t have a CA3. The ambient temperature was 90°today. From the past two days I will say that the motor is running cooler with the thicker phase wires with less statoraid.

Here’s an image of my current parameter settings, think I will raise the rated phase current to match the max phase current which is 200 A. feel like never have enough power for two wheels

 

[Eastwood]

So I turned the phase amps up to 150a today! Was at 100a. Tried to set at 200a but it automatically lowered to 150, so there’s the limit. Now I need to figure out how to hack this Sabvoton controller to give me the extra 50 Phase amps to a even 200amps , maybe Hardware and software upgrade..?

I have to say 150 phase amps pulls hard! I couldn’t stop laughing when I was going full throttle :lol:
Motor temps were up a little bit with the extra power but nothing unmanageable.

So when I ordered this mxus 3K I went with a 5T winding but as I’m looking at the pictures of the motor it has a 6, and I’ve read that mxus marks the winding on the base of the stator. If so that’s fine with me, if it’s a 6T because I was looking for hard acceleration. What do you guys think, could it be a 6T? I don’t have a tachometer to test right now, Plus it’s not that important I’m just curious..

Also if any of you guys have experience with unlocking Sabvoton controllers any input would be great!

 

[E-HP]

So when I ordered this mxus 3K I went with a 5T winding but as I’m looking at the pictures of the motor it has a 6, and I’ve read that mxus marks the winding on the base of the stator. If so that’s fine with me, if it’s a 6T because I was looking for hard acceleration.

If the simulator is right, then it looks like the faster wind motor accelerates harder, up to the top speed of the slower motor, with one and a half times the torque at that point (65NM vs 40NM):


https://ebikes.ca/tools/simulator.html?motor=MX3005&batt=cust_72_0.05_24&cont=cust_70_200_0.03_V&hp=0&axis=mph&frame=mountain&autothrot=false&throt=100&grade=0&bopen=true&cont_b=cust_70_200_0.03_V&motor_b=MX3006&batt_b=cust_72_0.05_24&hp_b=0

 

[Eastwood]

If the simulator is right, then it looks like the faster wind motor accelerates harder, up to the top speed of the slower motor, with one and a half times the torque at that point (65NM vs 40NM):

Well, The faster wind motor uses more battery to accelerate, this was another reason I went with a slow/5T as it’s more efficient with stop and go. technically you can get away with less battery with a slower wind motor compared to a 3T motor that’s going to run near 70 mph at 84 V. I don’t hold fast speeds for long and most of my riding is stop and go and especially off-road stuff. I love smashing step hills at full speed with the high torque motor :lol:

But yeah if I would’ve went with a 3T I would say 30ah minimum. With This 5T I’m good with 20ah, 20s 6p.. barely

 

[E-HP]

Well, The faster wind motor uses more battery to accelerate, this was another reason I went with a slow/5T as it’s more efficient with stop and go. technically you can get away with less battery with a slower wind motor compared to a 3T motor that’s going to run near 70 mph at 84 V. I don’t hold fast speeds for long and most of my riding is stop and go and especially off-road stuff. I love smashing step hills at full speed with the high torque motor :lol:

But yeah if I would’ve went with a 3T I would say 30ah minimum. With This 5T I’m good with 20ah, 20s 6p.. barely

Then just hold the faster motor's throttle at 85% instead of WOT and you have the exact same acceleration but slightly more efficient and cooler running:

 

[Eastwood]

Then just hold the faster motor's throttle at 85% instead of WOT and you have the exact same acceleration but slightly more efficient and cooler running:
6 vs 5 throttled.jpg

Wait are you suggesting that a fast wind motor has quicker acceleration? The whole point of getting a slow wind motor is to have more torque and faster acceleration. There’s many examples of bikes having the exact same controllers battery etc., and just different winding and the fast winding gets smoked off the line.

 

[Eastwood]

Then just hold the faster motor's throttle at 85% instead of WOT and you have the exact same acceleration but slightly more efficient and cooler running:
6 vs 5 throttled.jpg

Here’s an example of a 4T vs 5T Qsmotors
Nothing real scientific here just real world application
https://youtu.be/n9fYtyzV4Do

 

[E-HP]

Wait are you suggesting that a fast wind motor has quicker acceleration?

I'm just using the Grin simulator to see how the motors behave; didn't write any code.

I noticed the simulator is pretty accurate for certain behaviors when I dial in parameters for my bike, then change to various voltages; or at what speed the acceleration/torque noticeably drops off, 5 mph before top speed. Can't speak for other motors, but I think Grin physically tests them.

 

[raylo32]

This is too funny... about 20 years ago on a muscle car forum where everyone was modding their cars for quarter mile racing and road racing track sessions I remarked that soon enough we wouldn't be talking about superchargers, tunes, cams, and bigger injectors but instead we'd be talking about rewinding motors and juicing the battery voltage. And here we are!

 

[ZeroEm]

by raylo32 » Aug 21 2021 5:55am

This is too funny... about 20 years ago on a muscle car forum where everyone was modding their cars for quarter mile racing and road racing track sessions I remarked that soon enough we wouldn't be talking about superchargers, tunes, cams, and bigger injectors but instead we'd be talking about rewinding motors and juicing the battery voltage. And here we are!
Top

This is a great time in history, EV's smoke ICE in off line torque.

As far as Eastwood and E-HP discussion. This is the old Speed motor vs the Torque motor debate that goes back to the dawn of EV's.

Each one has it place. Many will pick one or the other and tell you why it is better. The one that is better is the one that fits your build.

I like 72V batteries they make pretty sparks. Don't like 20" rear wheels the spokes look odd. For me to marry these two things and keep my speed down I shoot for higher T motors. They do have better low end to a point for a set amount of amps. E-HP has a point about them dropping off at the end. I can run at 33 mph but a small grade my speed will drop before the motor starts pulling hard.
I want 28 mph that is 5 mph below top speed so don't get that lag.


I have a 7T and 5T here is the difference on my setup.

 

[E-HP]

E-HP has a point about them dropping off at the end. I can run at 33 mph but a small grade my speed will drop before the motor starts pulling hard.
I want 28 mph that is 5 mph below top speed so don't get that lag.

The drop off is interesting, and playing with the available current, I've noticed that the slope of the drop off remains the same, no matter how much current the motor has access to. The point where the drop off occurs changes as you feed it more current, until what I believe is saturation, at which point the torque curve is smooth (the drop off starts at 0mph) and at which point the motor performance doesn't change, not matter how much current is available (additional 100A, battery, 300A, phase in the last graph).

I'm hoping some of the forum experts could confirm whether this is what saturation looks like.



It seems that if you want maximum torque along the curve at a particular voltage, then the controller should be able to provide current up to the saturation point. That doesn't mean though that that huge amount of torque is usable down low unless you have wheelie bars. :lol:

 

[Eastwood]

I noticed the simulator is pretty accurate for certain behaviors when I dial in parameters for my bike, then change to various voltages; or at what speed the acceleration/torque noticeably drops off, 5 mph before top speed. Can't speak for other motors, but I think Grin physically tests them.

Yeah for sure the simulator is very accurate, but there’s more to acceleration than just torque and what we can see on the simulator. And to be honest I don’t believe I’m qualified to try to explain :lol:
That being said more torque equals more acceleration but there’s other factors like the windings etc.

 

[Eastwood]

This is too funny... about 20 years ago on a muscle car forum where everyone was modding their cars for quarter mile racing and road racing track sessions I remarked that soon enough we wouldn't be talking about superchargers, tunes, cams, and bigger injectors but instead we'd be talking about rewinding motors and juicing the battery voltage. And here we are!

Yeah for sure! It’s a ton of fun having a bicycle that has motorcycle performance and yet when people see it they think it’s just a bicycle
I keep looking for custom bikes in my area to race but I can’t find anyone. One day I seen a Sur-Run but the guy was with his little kid so we couldn’t race. He had his son a little mini electric dirtbike.

This reminds me of my drag racing days on my street bike. Still have that bike it’s basically a drag bike that is street legal. When the motor was in its prime it would run under 9sec 1/4 mile but I haven’t ridden in years. I’ve seen too many nasty accidents! I’ll stick with ebike power these days lol

 

[Eastwood]

Each one has it place. Many will pick one or the other and tell you why it is better. The one that is better is the one that fits your build.

Yes exactly, In my situation with the limited battery and being that I do a lot of stop and go that’s why I went with the 5T. It’s more efficient in my situation with stop and go and off roading. Also the motor runs much cooler at slower speeds. The 3T Wants to be pushed while the 5T you can cruise at the slow speeds without heating the motor. I did some testing today on a Greenway and I lowered the power setting so it would cruise at 5 mph and the motor actually got cooler. Then you hear most people with fast wind motors will say their motor gets too hot when they go slow.

Also another plus is I can use flux weakening to raise my top speed without with the slow wind. My wheels are 27.5 and when I’m fully charge I can hit almost 50 mph I think it’s right at 49 maybe 48

But yeah my next build will probably be a 3T but more of a motorcycle less bicycle style build. I want something at least 20,000 kW but I just don’t know how much those rear axles can take even with the QS205 or 273. Seems like there’s a saturation point where you’re just producing too much heat, so maybe I would consider a mid drive build.

 

[Eastwood]

unless you have wheelie bars. :lol:

Yeah I was thinking that today :lol: because I was laying on the handlebars trying to keep the front wheel down. I would love to test drive a bike that has like 400 phase amps or something just to see if there’s anyway I can manage to keep the wheel down.

 

[raylo32]

Remind me what battery you have that can push 200 amps into the hub? It's getting where you might be needing a Mr. Fusion machine like what made the DeLorean fly in BTtF.

unless you have wheelie bars. :lol:

Yeah I was thinking that today :lol: because I was laying on the handlebars trying to keep the front wheel down. I would love to test drive a bike that has like 400 phase amps or something just to see if there’s anyway I can manage to keep the wheel down.

 

[ZeroEm]

by Eastwood » Aug 21 2021 5:04pm

E-HP wrote: ↑Aug 21 2021 10:54am
unless you have wheelie bars. :lol:

Yeah I was thinking that today :lol: because I was laying on the handlebars trying to keep the front wheel down. I would love to test drive a bike that has like 400 phase amps or something just to see if there’s anyway I can manage to keep the wheel down.

Get a trike and make it wheelie.

 

[E-HP]

Remind me what battery you have that can push 200 amps into the hub? It's getting where you might be needing a Mr. Fusion machine like what made the DeLorean fly in BTtF.

I believe 3 of these in series would give you 240A at 16S:

https://hobbyking.com/en_us/turnigy-high-capacity-battery-20000mah-6s-12c-drone-lipo-pack-xt90.html?queryID=f13691799bf38b350ff20d52c8b4f599&objectID=78412&indexName=hbk_live_products_analytics

but I'd go with 6 of these; 2 sets of 16S, paralleled, for 360A, since they can take a 5Cc charge rate:

https://hobbyking.com/en_us/turnigy-graphene-professional-12000mah-6s-15c-lipo-pack-w-xt90.html?queryID=dff5e6bff100c2a688b5096ceb5c7c42&objectID=71592&indexName=hbk_live_products_analytics

 

[Eastwood]

Remind me what battery you have that can push 200 amps into the hub? It's getting where you might be needing a Mr. Fusion machine like what made the DeLorean fly in BTtF.

Well The battery produces 80 A continuously. It’s the Sabvoton controller that produces the high phase amps. That’s the beauty in buying these type of controllers they produce massive phase amps, typically you can double your power from what your battery actually produces.

The seller claims this battery can burst 180 A for a few seconds but I’ve always kept it under 80 and let the controller do the work. Well technically they told me it had a 60 amp bms but it doesn’t. I know another guy that has the same battery and he pushes his at 100 A continuous and it doesn’t get hot, they under claim their batteries for safety purposes. UPP batteries

But my next battery I will build myself and get some high discharge cells so I can beat it into the ground :lol:

 

[Eastwood]

It's getting where you might be needing a Mr. Fusion machine like what made the DeLorean fly in BTtF.

:lol: Yeah Fusion Schwinn Machine

if the controller is actually producing the total 200 phase amps that would be 16.800KW at full charge of 84v.

Or let’s say it’s just producing the rated phase amps at 150a that would be 12,600 KW to wheel.

If I had a CA3 I believe I could monitor the phase amps,
judging how fast I go from 0 to 50 it has to be at least 12,000+ kW to the rear wheel. The real insane acceleration is from 0 to 30mph

 

[E-HP]

If I had a CA3 I believe I could monitor the phase amps,
judging how fast I go from 0 to 50 it has to be at least 12,000+ kW to the rear wheel.

Unfortunately not. The CA get's it's current input by monitoring a shunt that imputes battery current. That, voltage, and wheel speed is are all of the inputs (besides button controls).