Ebike Hub Motor overheating cooling solution - HUBSINK OFFICIAL THREAD

Place for dealers to post items for sale.
User avatar
brumbrum
100 kW
100 kW
Posts: 1020
Joined: Oct 30, 2010 3:29 pm
Location: Wales U.K

Re: Hub Motor cooling solution - HUBSINK OFFICIAL THREAD

Post by brumbrum » Dec 19, 2017 7:07 am

Tats wrote:
Dec 19, 2017 6:57 am
And....an order in from Perth too. Rumour has it cricket Australia are interested in an experiment to cool Steve Smith’s form with the bat. :wink:
Thats a low blow :cry:

Haah, merry christmas :)

User avatar
brumbrum
100 kW
100 kW
Posts: 1020
Joined: Oct 30, 2010 3:29 pm
Location: Wales U.K

Re: Hub Motor cooling solution - HUBSINK OFFICIAL THREAD

Post by brumbrum » Dec 28, 2017 6:22 am

sketchism wrote:
Dec 18, 2017 6:28 am
hey Andrew your order went out in todays (monday morning) post so say 7 days to be safe
Just to let you know my hubsink arrived to my home today in the U.K. Great service all the was from Australia. :D

User avatar
brumbrum
100 kW
100 kW
Posts: 1020
Joined: Oct 30, 2010 3:29 pm
Location: Wales U.K

Re: Hub Motor cooling solution - HUBSINK OFFICIAL THREAD

Post by brumbrum » Dec 28, 2017 8:23 am

How much thermal paste am i supposed to get in the syringe? It is 5ml syringe but when i removed the wrapper it only has 2ml in it. Is this correct?

Image

sketchism
100 W
100 W
Posts: 157
Joined: Feb 17, 2016 8:35 am
Location: GC, Australia

Re: Hub Motor cooling solution - HUBSINK OFFICIAL THREAD

Post by sketchism » Dec 30, 2017 6:34 am

Hey mate I've never unwrapped the actual syringe but yep thats correct, each piece should have around .3ml on it and spread as thin as possible
Last edited by sketchism on Feb 08, 2018 5:27 am, edited 1 time in total.
Stay cool - www.hubsink.com (beta testing now open)

Nothing is fool proof to a sufficiently talented fool.

User avatar
brumbrum
100 kW
100 kW
Posts: 1020
Joined: Oct 30, 2010 3:29 pm
Location: Wales U.K

Re: Hub Motor cooling solution - HUBSINK OFFICIAL THREAD

Post by brumbrum » Dec 30, 2017 8:28 am

Hi Matt, we can continue this by email, so not to be double posting. It maybe worthwhile checking your stock.

Tats
1 kW
1 kW
Posts: 411
Joined: Apr 17, 2014 9:51 pm
Location: NOR Perth, worlds best kept secret, Australia

Re: Hub Motor cooling solution - HUBSINK OFFICIAL THREAD

Post by Tats » Jan 10, 2018 7:46 am

Installed on my H3540, dead easy. I had statorade already but this has dropped the temps further. My view is it’s about 5-10 degrees cooler.

redline2097
100 W
100 W
Posts: 135
Joined: Jun 18, 2015 1:43 am

Re: Hub Motor cooling solution - HUBSINK OFFICIAL THREAD

Post by redline2097 » Jan 11, 2018 4:29 am

Which hubmotor motor is lightest that can handle 3kw cont and 8kw peaks with hubsinks and ferro? Anything less weighting than Mxus 3000w V3?

SlowCo
10 kW
10 kW
Posts: 641
Joined: Jan 05, 2015 5:43 pm
Location: The Netherlands

Re: Hub Motor cooling solution - HUBSINK OFFICIAL THREAD

Post by SlowCo » Jan 11, 2018 7:41 am

redline2097 wrote:
Jan 11, 2018 4:29 am
Which hubmotor motor is lightest that can handle 3kw cont and 8kw peaks with hubsinks and ferro? Anything less weighting than Mxus 3000w V3?
I think you can get away with the Leaf or Edge 1500W 35mm stator motors if you're using Ferrofluid and Hubsinks. Ask the guys who use them here:
https://endless-sphere.com/forums/viewt ... 30&t=66489

https://endless-sphere.com/forums/viewt ... 30&t=81757

RollerBoy
100 µW
100 µW
Posts: 7
Joined: Oct 04, 2015 8:44 pm
Location: Atlanta, GA

Re: Hub Motor cooling solution - HUBSINK OFFICIAL THREAD

Post by RollerBoy » Jan 17, 2018 10:23 am

I put these on about 9 months ago. They were fun to install and very well crafted - and with Statorade / Ferrofluid the overheat issues on my commute have disappeared. Sketch had them shipped as soon as another batch of parts came in (yes, they had sold out!).
This is a 9C 30mm hub from Grin Technologies - it just so happens there is a close-up of a the same type motor on one of the earlier posts. Hope that this pictorial story-line of the installation is helpful/entertaining.
01  Unboxing.jpg
01 Unboxing.jpg (85.36 KiB) Viewed 425 times
Attachments
02 Unboxing.jpg
02 Unboxing.jpg (89.44 KiB) Viewed 425 times
03b Dirty Hub.jpg
03b Dirty Hub.jpg (72.43 KiB) Viewed 425 times
03b Use Windex.jpg
03b Use Windex.jpg (79.05 KiB) Viewed 425 times
03c  Prepared Hub.jpg
03c Prepared Hub.jpg (88.74 KiB) Viewed 425 times
04  Greasing 1.jpg
04 Greasing 1.jpg (72.45 KiB) Viewed 425 times
05  Greasing 2.jpg
05 Greasing 2.jpg (60 KiB) Viewed 425 times
06  Greasing 3.jpg
06 Greasing 3.jpg (90.07 KiB) Viewed 425 times
07  Greasing 4.jpg
07 Greasing 4.jpg (88.81 KiB) Viewed 425 times
10  Mounting 1.jpg
10 Mounting 1.jpg (97.61 KiB) Viewed 425 times
11  Mounting 2.jpg
11 Mounting 2.jpg (103.37 KiB) Viewed 425 times
12  Mounting 3.jpg
12 Mounting 3.jpg (86.6 KiB) Viewed 425 times
13  Wrong Tools 1.jpg
13 Wrong Tools 1.jpg (78.51 KiB) Viewed 425 times
16  Wrong Tools 2.jpg
16 Wrong Tools 2.jpg (90.24 KiB) Viewed 425 times
16 NO NO NO.jpg
16 NO NO NO.jpg (88.22 KiB) Viewed 425 times
16a Right Tools.jpg
16a Right Tools.jpg (106.03 KiB) Viewed 425 times
17  Better Tools.jpg
17 Better Tools.jpg (91.85 KiB) Viewed 425 times
18  Success.jpg
18 Success.jpg (69.39 KiB) Viewed 425 times
19  Typical Gap.jpg
19 Typical Gap.jpg (66.97 KiB) Viewed 425 times
20 Hats Off - Complete.jpg
20 Hats Off - Complete.jpg (83.48 KiB) Viewed 425 times

sketchism
100 W
100 W
Posts: 157
Joined: Feb 17, 2016 8:35 am
Location: GC, Australia

Re: Hub Motor cooling solution - HUBSINK OFFICIAL THREAD

Post by sketchism » Jan 17, 2018 5:59 pm

RollerBoy wrote:
Jan 17, 2018 10:23 am
I put these on about 9 months ago. They were fun to install and very well crafted - and with Statorade / Ferrofluid the overheat issues on my commute have disappeared.

Hope that this pictorial story-line of the installation is helpful/entertaining.
haha thanks man, as soon as i saw the image with the shifting spanners and pliers i was starting to worry about how you were going to manage the install, i love it lol
Stay cool - www.hubsink.com (beta testing now open)

Nothing is fool proof to a sufficiently talented fool.

User avatar
rberger
1 W
1 W
Posts: 52
Joined: Mar 09, 2015 2:10 am
Location: Saratoga, CA

Re: Ebike Hub Motor overheating cooling solution - HUBSINK OFFICIAL THREAD

Post by rberger » Feb 08, 2018 2:25 am

I just tried installing a set on my rear 20" Rim with a Crystalyte 3540 hub motor and it looks like there is not enough room to get the hubsink segment thru the spokes.

Help! I really would not like to have to disassemble the wheel. Rebuilding a wheel would stretch my mechanical abilities to the breaking point (I'm a software guy who tries to work on my trike :shock: )

Am I just doing something wrong or is this another case of physical reality being a drag?

I really want these on my motor, so looking for a solution, not a refund.
Here is a short video of me attempting to get it onto the hub. You can see what I've tried.
2011 ICE Adventure Trike Converted to 1500W DD Hub Pedalec in 2017

SlowCo
10 kW
10 kW
Posts: 641
Joined: Jan 05, 2015 5:43 pm
Location: The Netherlands

Re: Ebike Hub Motor overheating cooling solution - HUBSINK OFFICIAL THREAD

Post by SlowCo » Feb 08, 2018 10:04 am

You can probably get them in by removing 1 spoke. Just let the air out of the tire, unscrew the nipple and remove it, gently bend the spoke till you can get it out of the rim and rotate it out of the way. Then slide in all of the hubsink parts through the "hole". Re-attach the spoke in reverse. Good luck.

User avatar
mrbill
10 kW
10 kW
Posts: 515
Joined: Jun 10, 2008 6:47 pm
Location: Silicon Valley, California
Contact:

Re: Ebike Hub Motor overheating cooling solution - HUBSINK OFFICIAL THREAD

Post by mrbill » Feb 08, 2018 12:12 pm

Hi Robert:

SlowCo's recommendation to remove 1 spoke is how I got my Hubsinks onto my 406 wheel.

You should be aware that if you install Hubsinks on a 406 wheel you will probably need a 90-degree pump-head adapter of the kind used to inflate tires on disk wheels as most standard pump heads will not fit between the valve and the Hubsinks. This is a minor hassle as these adapters do not make a good seal with the valve, making it difficult to inflate the tire to a specific pressure using the pump's pressure gauge.

https://www.ebay.com/sch/sis.html?_item ... esta+Valve

You should also carry this adapter with you on the bike in case you need to re-inflate the tire after repairing a flat.

I noticed an increase in rolling resistance of a 406 DD hub filled with the usual amount of Statorade. It made the bike noticeably more difficult to pedal when the motor was not running, and overall efficiency was measurably reduced.

I think I have found a good compromise by filling a 35mm stator hub with about 3mL of Statorade (less than the recommended 1mL per 50 cm^2 of stator area), enough to have some beneficial cooling effect, but not so much that it noticeably reduces overall efficiency. You may wish to experiment to find the minimum amount of Statorade you can use and not overheat the motor.

Another thing to consider is that a 406 wheel gears-down the hub motor, allowing it to climb steeper hills and to produce less heat over it's typical RPM range. Since the motor is producing less heat in the first place, there is less need to find a way to remove it. You may find that Statorade by itself is sufficient.

What is your maximum observed motor temperature?
Bill Bushnell
http://mrbill.homeip.net/
Bike build thread can be seen here.

User avatar
amberwolf
100 GW
100 GW
Posts: 24552
Joined: Aug 17, 2009 6:43 am
Location: Phoenix, AZ, USA, Earth, Sol, Local Bubble, Orion Arm, Milky Way, Local Group
Contact:

Re: Ebike Hub Motor overheating cooling solution - HUBSINK OFFICIAL THREAD

Post by amberwolf » Feb 08, 2018 12:21 pm

mrbill wrote:
Feb 08, 2018 12:12 pm
You should be aware that if you install Hubsinks on a 406 wheel you will probably need a 90-degree pump-head adapter of the kind used to inflate tires on disk wheels as most standard pump heads will not fit between the valve and the Hubsinks. This is a minor hassle as these adapters do not make a good seal with the valve, making it difficult to inflate the tire to a specific pressure using the pump's pressure gauge.
Or if there's room for it, one of those 90-degree "RV wheel" adapters that you leave on the tire's valve stem. I use those on my SB Cruiser's rear wheels, because there's already not enough room for the hose's locking flip-tab to move to fully locked without hitting the spoke flanges. (or I I manage to get it locked, I can't get it unlocked and off without letting a fair bit of air back out of the tire).

This isn't the one I'm using but I"m sure it'd work just as well or better
https://www.rvupgradestore.com/90-Degre ... E8B40747F7

User avatar
rberger
1 W
1 W
Posts: 52
Joined: Mar 09, 2015 2:10 am
Location: Saratoga, CA

Re: Ebike Hub Motor overheating cooling solution - HUBSINK OFFICIAL THREAD

Post by rberger » Feb 09, 2018 4:10 am

Thanks MrBill and SlowCo for the excellent tip. I will give the removing the one spoke technique a try.

I have some of the 90 degree valve things so that's good.

Is a 406 Wheel different than the 20" Wheel I have 20" DM24 Alex Rim?

I purchased the motor (and the wheel built together) from Grin Tech and they put in the Statorade. I presume they did it optimally.

Is it possible that the Statorade has leaked out or otherwise something going on with that? When I had originally used the Grin Motor Simulator it seemed I shouldn't be having such problems. Though I may have used it wrong.

Now that its getting warmer, I'm seeing temps in the 100 to 105 (peak) degrees C range by the time I get half way up the hill. When it was cooler last week it happened about 75% up the hill. Today was particularly bad.

I stop when it gets around 100 degrees and let it cool down (and for me to catch my breath). The thermal rollback starts at 100 and I can't really go up the hill much more when rollback starts (Im not in the best of shape). I need pretty much full power even when I'm pedaling 150 to 250 watts.

I'm pretty sure MrBill has gone up this hill (Norton-Kittridge-Quickert Rd in Saratoga) I would be interested to hear if you think that my results do or don't make sense. Now my Trike is pretty heavy with the Crystalyte 3540 motor and 26Ah of 52v batteries (2 shark packs), and the stuff Im carrying when commuting: Approximately 70lbs. And I'm 255lbs. So its a lot of weight compared to MrBill and his recumbent.

The Strava Map of today's ride The first part of the trip is generally flat / very gradual climb and then when I get to Big Basin Way, the climb starts.

Here's a chart of the Motor Temp, Current and Speed by Time (Output of the Cycle Analyst)
cycle_analyst.2018-02-08_evening.png
cycle_analyst.2018-02-08_evening.png (38.89 KiB) Viewed 261 times
2011 ICE Adventure Trike Converted to 1500W DD Hub Pedalec in 2017

User avatar
mrbill
10 kW
10 kW
Posts: 515
Joined: Jun 10, 2008 6:47 pm
Location: Silicon Valley, California
Contact:

Re: Ebike Hub Motor overheating cooling solution - HUBSINK OFFICIAL THREAD

Post by mrbill » Feb 09, 2018 12:15 pm

Hi Robert:

Yes, your 20" wheel is an ISO 406 wheel. There are different nominal 20" wheel sizes, ISO 406 and ISO 451 being the most common. These are both considered 20" wheels. While the 451 rim is larger, the tires to fit that rim are smaller. The 406 rim is smaller, but the available tires are usually fatter. So, in the end they have similar working diameters, about 20 inches.

I would assume that Grin inserted the proper amount of Statorade to give the most cooling without adding adding too much rolling resistance. Unless you see evidence of the brown, oily fluid leaking out past the flange, through the insertion hole, or onto the rim, then the Statorade probably staying where it should.

I'm surprised your motor temperature is rising so quickly on that climb. Perhaps you are not contributing as much human power as you think. On grades over 12%, pedaling output can make a big difference in performance as the motor is already getting bogged down. Every 1 mph of additional climbing speed at less than 10 mph gives several percent greater efficiency. The stronger you are the more likely you will make it up the hill without stopping. Also, my over-temperature rollback range is 100-120C.

The problem with stopping for a cool-down is that the Statorade and Hubsinks are most effective when the wheel is rotating. When you're stopped, heat can only cross from the stator to the magnets at the spots where Statorade is bridging the gap, so the cooling rate is not much faster than without Statorade.

I have a 406 wheel on my bike right now that I'm testing. I will try to get out to your street this weekend and do the same climb. I don't log the stats over time as you do, but I can observe and report what I discover.
Bill Bushnell
http://mrbill.homeip.net/
Bike build thread can be seen here.

User avatar
rberger
1 W
1 W
Posts: 52
Joined: Mar 09, 2015 2:10 am
Location: Saratoga, CA

Re: Ebike Hub Motor overheating cooling solution - HUBSINK OFFICIAL THREAD

Post by rberger » Feb 10, 2018 3:32 am

mrbill wrote:
Feb 09, 2018 12:15 pm
I would assume that Grin inserted the proper amount of Statorade to give the most cooling without adding adding too much rolling resistance. Unless you see evidence of the brown, oily fluid leaking out past the flange, through the insertion hole, or onto the rim, then the Statorade probably staying where it should.
I'm actually a bit concerned. I don't see brown fluid around the flange, but I recently found brown liquid on the some of the phase connectors and hall switch connectors from the motor. I don't see how it got there though unless it somehow migrated up the wires out of the motor. I am wondering if I've lost Statorade.
mrbill wrote:
Feb 09, 2018 12:15 pm
I'm surprised your motor temperature is rising so quickly on that climb. Perhaps you are not contributing as much human power as you think. On grades over 12%, pedaling output can make a big difference in performance as the motor is already getting bogged down. Every 1 mph of additional climbing speed at less than 10 mph gives several percent greater efficiency. The stronger you are the more likely you will make it up the hill without stopping. Also, my over-temperature rollback range is 100-120C.
I believe my over-temperature rollback range is the same.

There are other days that I can get up the hill with significant less stopping. But they were about 10 degrees cooler ambient temperature. And my doctor has recently put me on a Calcium Blocker which I suspect is decreasing my already low stamina. The best I've done the hill has required about 3 stops to catch my breath from where Norton ends to Wildcat Ridge. This recent trip up that is charted was one of the worse. Its ether me degrading or there is something up with the motor / ambient temperature.

I'm attaching an updated chart that shows the CA's log of motor Watts (instead of Current) and Human Watts. I am actually pedaling a little more than I thought. But I do get tired pretty quick above 150 Watts. The right Y axis numbers are for the Motor and Human Watts. The left Y axis numbers represent Speed and Motor Temp.
cycle_analyst.2018-02-08_evening_chart.png
cycle_analyst.2018-02-08_evening_chart.png (50.02 KiB) Viewed 210 times
mrbill wrote:
Feb 09, 2018 12:15 pm
I have a 406 wheel on my bike right now that I'm testing. I will try to get out to your street this weekend and do the same climb. I don't log the stats over time as you do, but I can observe and report what I discover.
I'm looking forward to hearing your results! I'm hoping to have time to put on the Hubsinks this weekend.

Thanks again for all the help.
2011 ICE Adventure Trike Converted to 1500W DD Hub Pedalec in 2017

User avatar
rberger
1 W
1 W
Posts: 52
Joined: Mar 09, 2015 2:10 am
Location: Saratoga, CA

Re: Ebike Hub Motor overheating cooling solution - HUBSINK OFFICIAL THREAD

Post by rberger » Feb 12, 2018 4:17 am

Got the Hubsinks on my hub/wheel. The "remove one spoke" technique worked well. They look very cool, so hopefully it cools the motor :o
IMG_2153.jpg
IMG_2153.jpg (31.96 KiB) Viewed 165 times
I was even able to fill the tire with air without the 90 degree adapter.

Will try it out tomorrow.

I wonder if there is a way to tell if I have lost the Ferrofluid. I don't see gross evidence, but did see some brown liquid residue in and around the connectors. Grin injects the fluid thru a hole in one of the brake screw points I believe. Not sure what insures it doesn't leak out...
2011 ICE Adventure Trike Converted to 1500W DD Hub Pedalec in 2017

User avatar
amberwolf
100 GW
100 GW
Posts: 24552
Joined: Aug 17, 2009 6:43 am
Location: Phoenix, AZ, USA, Earth, Sol, Local Bubble, Orion Arm, Milky Way, Local Group
Contact:

Re: Ebike Hub Motor overheating cooling solution - HUBSINK OFFICIAL THREAD

Post by amberwolf » Feb 12, 2018 4:26 am

Magnetism.

Once it's on the magnets it'll stay there, unless there's a gap in the covers and rotational forces exceed that of the magnetism.

It can't flow back to the axle area, only further outward.

SlowCo
10 kW
10 kW
Posts: 641
Joined: Jan 05, 2015 5:43 pm
Location: The Netherlands

Re: Ebike Hub Motor overheating cooling solution - HUBSINK OFFICIAL THREAD

Post by SlowCo » Feb 12, 2018 7:41 am

rberger wrote:
Feb 12, 2018 4:17 am
Got the Hubsinks on my hub/wheel. The "remove one spoke" technique worked well.

You're welcome :wink:
rberger wrote:
Feb 12, 2018 4:17 am
I wonder if there is a way to tell if I have lost the Ferrofluid.
Do you have a Cycle Analyst on your trike? If so, just lift the rear wheel off the ground and see what the power consumption (Amps/Watts) is unloaded at top speed. Then post here or ask Grin to confirm if that is a wattage they also see when filled with enough Ferro Fluid. The no load power consumption should be a little higher with enough FF in the hub than without or too little.

User avatar
mrbill
10 kW
10 kW
Posts: 515
Joined: Jun 10, 2008 6:47 pm
Location: Silicon Valley, California
Contact:

Re: Ebike Hub Motor overheating cooling solution - HUBSINK OFFICIAL THREAD

Post by mrbill » Feb 12, 2018 1:16 pm

rberger wrote:
Feb 10, 2018 3:32 am
I'm looking forward to hearing your results! I'm hoping to have time to put on the Hubsinks this weekend.
Thanks again for all the help.
Hi Robert:

Yesterday morning I rode the following route that started with a climb into your neighborhood on the bike shown in my avatar.

https://www.strava.com/activities/1403501052/analysis

I rode up the hill, without stopping, as far as the top of On Orbit Lane, the site of the steepest continuous grade.

Maximum temperature was 93.5C on the climb and 93.6C on the descent (near Bohlman and Norton) while motor braking held bike to 17.5 mph until near the bottom when the controller cut back motor braking to limit voltage across the battery. Ambient temperature was about 15C.

Power was limited to 1000 watts pulled from the battery (as observed on and limited by the CA3). Weight of bike+rider was 127kg. Speed on the steepest parts was around 10kph. If you zoom in on the profile showing the first major climb, you can see speed detail. Disregard Strava's power profile as this is merely an estimate not a direct measurement.

As I mentioned above I am using Statorade and Hubsinks, but only about 3mL of the former across a 35mm stator, which probably contributes only slightly to the cooling of the motor. A full dose of Statorade would probably give lower maximum temperature figures at the expense of additional drag. I may add some Statorade in spite of the additional drag if I observe overheating during hotter weather.
Bill Bushnell
http://mrbill.homeip.net/
Bike build thread can be seen here.

User avatar
rberger
1 W
1 W
Posts: 52
Joined: Mar 09, 2015 2:10 am
Location: Saratoga, CA

Re: Ebike Hub Motor overheating cooling solution - HUBSINK OFFICIAL THREAD

Post by rberger » Feb 12, 2018 9:31 pm

Well MrBill's ride is pretty embarrassing and inspirational; Going up my hill that I'm struggling with was just a little side jaunt to an amazing outing all over the Santa Cruz Mountains! Something I hope to be able to do someday.

So the main difference is me and my equipment is about 150kg vs MrBill is 127kg. MrBill gets away with 1000 Watts max and I'm peaking at just under 1900 watts. And of course I'm not in very good shape. As a side note, my Doctor put me on a Calcium Blocker on Jan 9 and then changed it on Feb 2nd. It looks like that has dropped my stamina even lower than before.

I took the hill today with the new Hubsink's installed. Unfortunately for science sake, the ambient temperature was about 10 to 15 degrees F lower than the previous time that I charted. Also the trip before the hill was much shorter with a break for coffee before I went up the hill, so the motor had much less time to warm up before going up the hill.

But comparing the previous chart and this one, I would say that something is amiss, like maybe my Statorade has somehow leaked out. The temperature still peaked at 96 degrees C. Its lower than before but the conditions seems that they would have lowered the temperature about that much... I'll try SlowCo's suggested experiment as soon as I can.
cycle_analyst.2018-02-12_afternoon.png
cycle_analyst.2018-02-12_afternoon.png (48.62 KiB) Viewed 121 times
2011 ICE Adventure Trike Converted to 1500W DD Hub Pedalec in 2017

User avatar
mrbill
10 kW
10 kW
Posts: 515
Joined: Jun 10, 2008 6:47 pm
Location: Silicon Valley, California
Contact:

Re: Ebike Hub Motor overheating cooling solution - HUBSINK OFFICIAL THREAD

Post by mrbill » Feb 12, 2018 10:47 pm

Hi Robert:

What controller are you using to drive your motor? Is there a chance that the controller is not tuned well to the motor? Does the controller get hot to the touch? The controller should seldom get more than detectably warm to the touch.

Your speeds are similar to mine, but your power is 50-75% higher. Some of that is due to weight difference, and some to pedaling input. I was pedaling pretty hard on the steep stuff.

With a larger drive wheel I have found that on long, steep (>12%) grades, the motor temperature may rise into the rollback zone. When the CA3 rolls back power, the temperature usually stabilizes at a lower power level, say 500-600 watts that I can hold indefinitely. Could you try your climb again, but this time set the power limit on your CA3 to 1000 watts? You will climb more slowly, but you may find you no longer need to stop for a cool-down, and your overall time may be lower. You may need trial and error to find the maximum power you can use on your hill and not be forced to stop for a cool-down.
Bill Bushnell
http://mrbill.homeip.net/
Bike build thread can be seen here.

User avatar
rberger
1 W
1 W
Posts: 52
Joined: Mar 09, 2015 2:10 am
Location: Saratoga, CA

Re: Ebike Hub Motor overheating cooling solution - HUBSINK OFFICIAL THREAD

Post by rberger » Feb 13, 2018 4:29 am

mrbill wrote:
Feb 12, 2018 10:47 pm
What controller are you using to drive your motor? Is there a chance that the controller is not tuned well to the motor? Does the controller get hot to the touch? The controller should seldom get more than detectably warm to the touch.
I'm using a Phaserunner 2.0 with a big heatsink on it. I'm logging the data from there too. The Phaserunner internal temp didn't get above 66 Deg C even on the warm day. I'll attach a graph with that and motor temp.
cycle_analyst.2018-02-08_evening.temp_charts.png
cycle_analyst.2018-02-08_evening.temp_charts.png (40.84 KiB) Viewed 99 times
mrbill wrote:
Feb 12, 2018 10:47 pm
Your speeds are similar to mine, but your power is 50-75% higher. Some of that is due to weight difference, and some to pedaling input. I was pedaling pretty hard on the steep stuff.

With a larger drive wheel I have found that on long, steep (>12%) grades, the motor temperature may rise into the rollback zone. When the CA3 rolls back power, the temperature usually stabilizes at a lower power level, say 500-600 watts that I can hold indefinitely. Could you try your climb again, but this time set the power limit on your CA3 to 1000 watts? You will climb more slowly, but you may find you no longer need to stop for a cool-down, and your overall time may be lower. You may need trial and error to find the maximum power you can use on your hill and not be forced to stop for a cool-down.
I don't think I could get far up the hill with 1000 watts. There are points when it drops to 1300 or 1500 watts I have a lot of problems going. I really have a breath stamina problem that may be due to a medical condition and / or the drugs they are giving me for Arrhythmia.

Today ether due to the cooler ambient temp or the hubsinks, I never went into motor rollback zone. But I do very easily go into my Body's Rollback Zone! So at least right now I can't pedal 180 to 200+ watts for very long without getting out of breath. So I have to stop about 3 to 6 or more times to get up the hill without dying even if the motor doesn't go into rollback. I do hope to improve my stamina. The pauses in today's chart were due to me pooping out, not the motor.

What I wish for is that I didn't have to also contend with the motor pooping out too. Especially when it poops out in a dangerous point in the road (i.e. a blind curve where a car might not see me until too late).

I was hoping that the Hubsinks would give me enough thermal headroom to not worry about overheating and just worry about me being able to get up the hill even if I had to stop to catch my breath. Extrapolating today's results makes it seem that my motor will overheat even with the Hubsink.

With your help and relooking at the Grin motor simulator, the problem does seem that I am going to slow and the motor is not running anywhere near its best efficiency. The only other thing might be that there is some issue with the Statorade or some other issue, but I'm begging to think that the overall system plus my weight and inability to continuously generate 200 watts means that I'm doomed to overheating in warm weather at least.

I originally interpreted the motor simulator to say that with the 3540+statorade 150kg total weight, with 52v / 40A of power and full throttle, 100 wats of pedaling on a 12% grade, I should go 17.7mph and "Overheat In never". Though it also says Final Temp 115 Deg C.

In reality I'm going 7mph and that makes the motor run much less efficient. At that speed the motor simulator says I will overheat in 5.3min with a final temp > 250 degrees!

Now the whole hill is not 12%, but still.. Not really sure what's up. Physical reality is such a drag.

One other thing is I can't get my system to consistently pump out full power/torque. There are times I'm pedaling like crazy (200+ Human Watts on the CA), have the CA multiple for my human power set to 15, and I'm only getting 1200 to 1300 Watts (according to the readout on the CA). I'm using the Thun Torque Sensor hooked to the CA. Other times, usually when I don't need it so much, its operating at 1800+ watts.

The direct throttle never seems to get the system going anywhere near full power. I'm pretty sure I got the in and out voltages right.

Is there any chance that if the system was really operating at full power more, that I would be able to maintain the more efficient speed? I'm not going to be able to generate more human watts.

I still have to try the experiment SlowCo suggested on testing for Statorade.

Open to any other suggestions.
2011 ICE Adventure Trike Converted to 1500W DD Hub Pedalec in 2017

User avatar
mrbill
10 kW
10 kW
Posts: 515
Joined: Jun 10, 2008 6:47 pm
Location: Silicon Valley, California
Contact:

Re: Ebike Hub Motor overheating cooling solution - HUBSINK OFFICIAL THREAD

Post by mrbill » Feb 13, 2018 11:37 am

Hi Robert:

I'll assume you've tuned the Phaserunner for your motor.

If you're seeing 66C at the controller and the motor is overheating, that's a sure sign that you're running the motor into the "heater zone", where too much power is being converted into heat.

You might be better served by a slower wind motor of similar size, a motor happier running at a lower RPM, though limited in top-end speed. But, with the number of cooling stops you require and to keep you from going into the red zone, I think you will need a bigger motor, a geared hub motor, or a crank-drive/mid-drive motor.

A bigger motor might be something like a slow-wind MXUS (kv of 7-8) configured for your dropout width (135mm?), or one of the other larger hub motors such as one of the Crystalyte Crown series. You could also consider a geared hub motor. An appropriate through-the-gears motor might be something like the crank-drive Bafang BBSHD or Stokemonkey. A crank-drive motor may have enough torque to get you up the hill without your pedaling at all. I configured my crank-drive motors so that I could gear them low enough to haul me up a 25-30% grade without pedaling as I, too, have a history of heart arrhythmia and wanted the bike to bail me out if my heart misbehaved.

But, there's always a downside. With a larger DD hub motor you will give up your rear cluster, settling for at most 2 rear gears, usually only 1. With the non-DD hub motors you will give up the ability to motor-brake on the steep descent when leaving your house, putting more wear on your friction brakes. Your friction brakes may overheat by the time you reach the bottom of the hill, and you will go through a set of pads every 500-1000 miles or so. Overheating rim brakes can cause tire blow-offs, and overheating disk brakes can cause extreme noise and vibration through the hub and spokes that can lead to premature spoke breakage.

Although it adds complexity and reduces reliability, a two-motor/two-controller system may be required in your situation: a through-the-gears motor for the climb and a DD hub for motor braking (regeneration or plugging) on the descent.

You living arrangement, 500 meters above the valley on a steep road (up to 20% grade), limited human power output, and greater than average total weight, makes for a difficult design problem with the usual e-bike components.
Bill Bushnell
http://mrbill.homeip.net/
Bike build thread can be seen here.

Post Reply