Odd thing

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Lee30   100 µW

100 µW
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Joined: Mar 13 2019 2:13pm

Odd thing

Post by Lee30 » Mar 14 2019 1:46pm

Odd thing. This only does it at 20mph? Say I am travelling along on a flat road, motor power only. I get up to 20mph and keep it there for a short while, then reduce the throttle slightly, even though the power meter says that I have reduced power, I am still doing 20mph? Ok, 15 mph reads 3 bars on the meter, 20 mph, 4 bars initially, but after a short while, I can get it down to 3 bars, still doing 20 mph?

JBG   1 mW

1 mW
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Location: New York City

Re: Odd thing

Post by JBG » Mar 14 2019 8:50pm

Of course that’s what’s happening. It takes more power to accelerate than to maintain speed.
My first build: 36V 500W hardtail

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dogman dan   100 GW

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Joined: May 17 2008 12:53pm
Location: Las Cruces New Mexico USA

Re: Odd thing

Post by dogman dan » Mar 15 2019 7:33am

And the motor may actually operate more efficiently at 20 mph.

But some of what you are seeing is just a time lag on that type of power meter. So you may be seeing a combination of things, efficiency improving, less needed to maintain 20 mph than it needed to get from 15 to 20 mph, and a small time lag on the input averaging built into the meter.

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neptronix   100 GW

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Joined: Jun 15 2010 5:56pm
Location: California refugee living in Utah, USA

Re: Odd thing

Post by neptronix » Mar 15 2019 9:15am

You should really get a watt/volt/amp metering device. It will teach you a lot about power consumption. Whatever display you have will not indicate much of use ( what does a bar represent, exactly? :roll: ).

These have always been cheap and pretty reliable:

https://hobbyking.com/en_us/turnigy-180 ... lsrc=aw.ds
Efficiency is everything :bolt:

My first major build: 8T MAC motor on a Trek 4500.
The new all-arounder: Leafmotor 1500w on a Turner O2 full suspension.
The monster scooter: ? on a Cannondale Semi Recumbent.

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MadRhino   100 GW

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Joined: Sep 03 2010 5:28pm
Location: Montreal QC Canada

Re: Odd thing

Post by MadRhino » Mar 16 2019 10:09am

neptronix wrote:
Mar 15 2019 9:15am

... what does a bar represent, exactly? :roll: ).
14.5 psi ?
Make it fool-proof, and I will make a better fool.
Current bikes
Street: https://s20.postimg.org/ewrvugywt/Session_04_2015.jpg
Dirt: https://s20.postimg.org/lbqwr55ml/IMG_0157.jpg

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