dogman dan
1 PW
The course. 1200 vertical feet gained in 4 miles. About a mile of the steepest part is 7%.
San Augustine pass near Organ NM on HWY 70, east of Las Cruces. From Brahman exit to the top.
The temperature. Over 100F official temp.
Motor temps measured at axle, and 35 F added to that. Street temp is the motor temp at the start of the ride.
Humidity. Low. Low humidity lessens air cooling dramatically. We have very low humidity in June in NM, below 10%. In June lots of air cooled stuff dies.
The ride. Full throttle, no pedaling, 48v pingbattery. 180 pound rider.
The controller. Stock kit controllers.
The motors. E-Bikekit 9 continent 2807/9x7. 9 continent 6x10. High Tech Bikes Aotema. Fusin 48v gearmotor kit.
Controller heat. I didn't measure it, but all three kits controllers got hot enough to be hard to touch for long. But nothing went poof on the direct drive motors. 8) When the gearmotor quit, the controller did not feel particularly hot.
Any others that have different motors, do a similar test if you have hot enough weather. Telling us your motor stays cool at 85F does no good, we know that already. If you must, climb a hill repeatedly till you have a similar vertical distance of climbing in.
E-Bikekit 2807 (9x7 9 continent)
Temp at start ------------------------101F -------106 out on the road.
Wind -----------------------------------10 mph tailwind. Helps the motor climb faster, but a tailwind cuts wind cooling too.
Humidity--------------------------------7%
Temp at top of pass------------------151F Adjusted by adding 35F for actual temp inside the hub.
Soak temp at top---------------------121F After you stop, temp continues to climb after wind cooling stops. I don't have data to know how many degrees to add for this number. So it represents pretty close to the temp inside, 10 min or so after you stop.
Heat gain------------------------------50F 156 minus street temp of 106.
Amp hours used ----------------------4.125
Watt hours used---------------------208.1
Volts at the top----------------------52.5 Resting voltage.
Typical watts while climbing-------1100
Typical speed. ----------------------19 mph on the 7% part. 25 mph on the flatter part.
Temp after riding back down. ----143F
Summary. Climbs good with decent speed on the steep part. Could clearly have climbed farther, since 180F is what I consider a practical limit for motor heat. The temp at the bottom after riding back down shows that direct drive motors still make heat descending with the throttle off.
High Tech Bikes Aotema kit.
Temp at start---------------------103F ---108 on the road.
Wind ------------------------------10 mph tailwind
Humidity---------------------------7%
Temp at top of the pass---------155F
Soak temp at top----------------143F
Heat gain------------------------47F
Amp hours used-----------------4.17
Watthours used----------------212.74
Volts at the top-----------------52.5
Typical watts------------------1050--1180
Typical speed------------------16-17 mph on the 7% part. 28 mph on the flat part.
Temp after riding back down---156F
Summary---------------------- This motor clearly struggles more than the 9 continent 2807 on the steepest bit, but suprisingly made about the same heat, and used about the same watthours to get up the mountain. But had I continued, the numbers for the soak temp at the top show that this motor has a harder time cooling off once hot compared to the 9 continent motor. After 10 min the 9c had started to cool back off, while the Aotema kept on getting hotter. Both got to the same top temp, but the Aotema clearly held on to that heat longer. At 48v it's hill performance is not bad at all, but clearly it prefers 5% to 7%.
Update. soon after the test a problem this motor had been having for awhile got worse. An intermittent stutter or loss of power. It seemed to get worse with more volts when I tried a different controller, or when pulling max amps. This problem was present before the heat test, but the meltoff seems to have made whatever is wrong worse. Opening it up, there was no obvious signs of toasted windings. With all the miles on this motor, I suspect it was just something more age related than the melt test. It happens with any controller I try it with so I think it may be the windings. new connectors did not fix it, so it's not likely to be that, and the wires look ok.
9 continent 6x10 motor. Very slow winding motor.
Temp -----------------------------104F-----113 on the road
Wind -------------------------------12 mph tailwind
Humidity----------------------------7%
Temp at top of pass--------------150 F
Soak temp at top-----------------117
Heat gain-------------------------38F
Amp hours-----------------------3.65
Watt hours------------------------187
Volts at top-----------------------52.7
Typical watts--------------------800-900 1000 watts on steepest grade.
Typical speed---------------------15 mph on 7% 19 mph on flat part
Temp at bottom after riding down--110F
Summary. This motor climbs cool. Slower yes, but 15 mph isn't really that slow for climbing 7%. It simply makes less heat, uses less watts, and unlike the other motors this one reached it's max temp half way up the pass and never got hotter. That means I could have rode till the battery died on that grade and never gotten much hotter since the motor could shed the heat as fast as it made it. EVEN IN 112 F ROAD TEMPS! Wow. The dramatically different soak temperature shows there was no extra heat stored inside the motor when I reached the top. With a 48v battery, this motor could cross continents and never smoke itself on a hill.
Fusin 48v gearmotor.
Distance------------------ 3 miles
Temp ---------------------104F----108 street temp
Wind----------------------- 5-10 mph headwind
Humidity --------------------10%
Temp at top of pass--------? temp at end of test. 190F
Soak temp------------------? off the scale, presumably above 200F
Watthours---------------------168.3
Amp hours--------------------3.28
Typical watts-------------------750
Speed---------------------------10 mph---20 on the flatter part
Temp at the bottom-----------190
Volts at top----------------------? ---52.8 at end of test.
Summary------- By now you must be thinking, what happened? About 3 miles up on the test the motor stuttered a few seconds, quit, then ran a few more seconds, and quit for good. I suspect I melted a hall sensor. At that point temps were nearly 160F at the axle, and assuming 30-40F hotter inside, the motor was above what I consider safe, 180F. However, gearmotors don't shed heat as readily as direct drive motors, so perhaps the actual temps inside are even more than 40F higher. Who knows? the axle is pretty skinny, and I never got a sensor wire set actually inside a hubmotor. So maybe I melted it down even hotter than I think. But the bottom line is. In really hot weather, you better be carefull pushing your small gearmotors. It clearly struggled a lot more than the direct drive motors to climb the mountain. The Fusin kit has the three position switch, where you ride in the fast one till it slows too much, then move to position 2 and the motors performance improves. Finally you bog down in 2, and switch to slow to keep the motor happy climbing steep hills. This is how I was riding it. But obviously by the speed of the climb, and the end result, this motor couldn't climb the hill with no help from the rider.
Update. Finally got around to taking the fusin motor apart. Not obvious exactly what melted, but there was some loose balls of solder rolling around in there that hadn't been there before. So clearly this motor got cooked pretty hot.
San Augustine pass near Organ NM on HWY 70, east of Las Cruces. From Brahman exit to the top.
The temperature. Over 100F official temp.
Motor temps measured at axle, and 35 F added to that. Street temp is the motor temp at the start of the ride.
Humidity. Low. Low humidity lessens air cooling dramatically. We have very low humidity in June in NM, below 10%. In June lots of air cooled stuff dies.
The ride. Full throttle, no pedaling, 48v pingbattery. 180 pound rider.
The controller. Stock kit controllers.
The motors. E-Bikekit 9 continent 2807/9x7. 9 continent 6x10. High Tech Bikes Aotema. Fusin 48v gearmotor kit.
Controller heat. I didn't measure it, but all three kits controllers got hot enough to be hard to touch for long. But nothing went poof on the direct drive motors. 8) When the gearmotor quit, the controller did not feel particularly hot.
Any others that have different motors, do a similar test if you have hot enough weather. Telling us your motor stays cool at 85F does no good, we know that already. If you must, climb a hill repeatedly till you have a similar vertical distance of climbing in.
E-Bikekit 2807 (9x7 9 continent)
Temp at start ------------------------101F -------106 out on the road.
Wind -----------------------------------10 mph tailwind. Helps the motor climb faster, but a tailwind cuts wind cooling too.
Humidity--------------------------------7%
Temp at top of pass------------------151F Adjusted by adding 35F for actual temp inside the hub.
Soak temp at top---------------------121F After you stop, temp continues to climb after wind cooling stops. I don't have data to know how many degrees to add for this number. So it represents pretty close to the temp inside, 10 min or so after you stop.
Heat gain------------------------------50F 156 minus street temp of 106.
Amp hours used ----------------------4.125
Watt hours used---------------------208.1
Volts at the top----------------------52.5 Resting voltage.
Typical watts while climbing-------1100
Typical speed. ----------------------19 mph on the 7% part. 25 mph on the flatter part.
Temp after riding back down. ----143F
Summary. Climbs good with decent speed on the steep part. Could clearly have climbed farther, since 180F is what I consider a practical limit for motor heat. The temp at the bottom after riding back down shows that direct drive motors still make heat descending with the throttle off.
High Tech Bikes Aotema kit.
Temp at start---------------------103F ---108 on the road.
Wind ------------------------------10 mph tailwind
Humidity---------------------------7%
Temp at top of the pass---------155F
Soak temp at top----------------143F
Heat gain------------------------47F
Amp hours used-----------------4.17
Watthours used----------------212.74
Volts at the top-----------------52.5
Typical watts------------------1050--1180
Typical speed------------------16-17 mph on the 7% part. 28 mph on the flat part.
Temp after riding back down---156F
Summary---------------------- This motor clearly struggles more than the 9 continent 2807 on the steepest bit, but suprisingly made about the same heat, and used about the same watthours to get up the mountain. But had I continued, the numbers for the soak temp at the top show that this motor has a harder time cooling off once hot compared to the 9 continent motor. After 10 min the 9c had started to cool back off, while the Aotema kept on getting hotter. Both got to the same top temp, but the Aotema clearly held on to that heat longer. At 48v it's hill performance is not bad at all, but clearly it prefers 5% to 7%.
Update. soon after the test a problem this motor had been having for awhile got worse. An intermittent stutter or loss of power. It seemed to get worse with more volts when I tried a different controller, or when pulling max amps. This problem was present before the heat test, but the meltoff seems to have made whatever is wrong worse. Opening it up, there was no obvious signs of toasted windings. With all the miles on this motor, I suspect it was just something more age related than the melt test. It happens with any controller I try it with so I think it may be the windings. new connectors did not fix it, so it's not likely to be that, and the wires look ok.
9 continent 6x10 motor. Very slow winding motor.
Temp -----------------------------104F-----113 on the road
Wind -------------------------------12 mph tailwind
Humidity----------------------------7%
Temp at top of pass--------------150 F
Soak temp at top-----------------117
Heat gain-------------------------38F
Amp hours-----------------------3.65
Watt hours------------------------187
Volts at top-----------------------52.7
Typical watts--------------------800-900 1000 watts on steepest grade.
Typical speed---------------------15 mph on 7% 19 mph on flat part
Temp at bottom after riding down--110F
Summary. This motor climbs cool. Slower yes, but 15 mph isn't really that slow for climbing 7%. It simply makes less heat, uses less watts, and unlike the other motors this one reached it's max temp half way up the pass and never got hotter. That means I could have rode till the battery died on that grade and never gotten much hotter since the motor could shed the heat as fast as it made it. EVEN IN 112 F ROAD TEMPS! Wow. The dramatically different soak temperature shows there was no extra heat stored inside the motor when I reached the top. With a 48v battery, this motor could cross continents and never smoke itself on a hill.
Fusin 48v gearmotor.
Distance------------------ 3 miles
Temp ---------------------104F----108 street temp
Wind----------------------- 5-10 mph headwind
Humidity --------------------10%
Temp at top of pass--------? temp at end of test. 190F
Soak temp------------------? off the scale, presumably above 200F
Watthours---------------------168.3
Amp hours--------------------3.28
Typical watts-------------------750
Speed---------------------------10 mph---20 on the flatter part
Temp at the bottom-----------190
Volts at top----------------------? ---52.8 at end of test.
Summary------- By now you must be thinking, what happened? About 3 miles up on the test the motor stuttered a few seconds, quit, then ran a few more seconds, and quit for good. I suspect I melted a hall sensor. At that point temps were nearly 160F at the axle, and assuming 30-40F hotter inside, the motor was above what I consider safe, 180F. However, gearmotors don't shed heat as readily as direct drive motors, so perhaps the actual temps inside are even more than 40F higher. Who knows? the axle is pretty skinny, and I never got a sensor wire set actually inside a hubmotor. So maybe I melted it down even hotter than I think. But the bottom line is. In really hot weather, you better be carefull pushing your small gearmotors. It clearly struggled a lot more than the direct drive motors to climb the mountain. The Fusin kit has the three position switch, where you ride in the fast one till it slows too much, then move to position 2 and the motors performance improves. Finally you bog down in 2, and switch to slow to keep the motor happy climbing steep hills. This is how I was riding it. But obviously by the speed of the climb, and the end result, this motor couldn't climb the hill with no help from the rider.
Update. Finally got around to taking the fusin motor apart. Not obvious exactly what melted, but there was some loose balls of solder rolling around in there that hadn't been there before. So clearly this motor got cooked pretty hot.