Search found 14471 matches

by John in CR
Sep 29 2020 12:23pm
Forum: E-Bike Technical
Topic: FEM Dropout analysis - max force ?
Replies: 18
Views: 494

Re: FEM Dropout analysis - max force ?

- So just adding a small clamping bolt increases torque handling from 35Nm to 60Nm - nearly double. "Nearly double" is not anywhere close to the real world benefit. There is never precision machining of the dropouts to the axle size, and a press fit would be impractical anyway, so there is always p...
by John in CR
Sep 29 2020 6:46am
Forum: E-Bike Technical
Topic: FEM Dropout analysis - max force ?
Replies: 18
Views: 494

Re: FEM Dropout analysis - max force ?

Newton meters in the dropout is crazy newtons of force at the small radius, so yes it's thousands of newtons of force in those dropouts.
by John in CR
Sep 29 2020 6:34am
Forum: E-Bike General Discussion
Topic: Leafmotor project
Replies: 60
Views: 1263

Re: Leafmotor project

[apples and oranges comparisons not worthy of quoting] [apples and oranges comparisons not worthy of quoting] Guys, you are wasting everyone's time by using apples and oranges comparisons to support your erroneous conclusions, and it is a disservice to the membership of the forum to propagate misle...
by John in CR
Sep 28 2020 6:50pm
Forum: E-Bike General Discussion
Topic: Leafmotor project
Replies: 60
Views: 1263

Re: Leafmotor project

Others have different speed objectives, but it's always beneficial to get the right kV for the job, rather than one that's faster. Yeah, it's beneficial - a long as you don't get too "wound up" over a couple percentage points that aren't going to make the kind of difference that anyone would notice...
by John in CR
Sep 28 2020 10:56am
Forum: E-Bike General Discussion
Topic: Leafmotor project
Replies: 60
Views: 1263

Re: Leafmotor project

It's not just hotrodders who burn up their hubbies. It's regular people just trying to get up a hill too, and the hill doesn't have to be that steep either. They just combined the wrong conditions with a wheel size that caused heat and less range from the start. You mean folks who use too fast a wi...
by John in CR
Sep 28 2020 3:30am
Forum: E-Bike General Discussion
Topic: Leafmotor project
Replies: 60
Views: 1263

Re: Leafmotor project

The motor can be ordered with an inexpensive controller, which is spec'ed for the motor. It also comes with your choice of winding at no charge. Why would any sane, not obsessed person choose to go on an exotic controller and battery quest rather than just choose the right winding for the job (purp...
by John in CR
Sep 28 2020 1:36am
Forum: E-Bike General Discussion
Topic: Temporary replacement controller
Replies: 4
Views: 246

Re: Temporary replacement controller

As long as you can get either with irfb4110 mosfets, I've had good luck with with both Greentime's 18fet controller and YYK YuYangKing's 18fet with the advantage going to the YYK due to android phone programmability (maybe they have an iPhone app now, but no idea since I'd never own an i-anything.) ...
by John in CR
Sep 28 2020 1:11am
Forum: E-Bike General Discussion
Topic: Sur Ron vs. DIY hub motor bike?? Which would you recommend?
Replies: 3
Views: 246

Re: Sur Ron vs. DIY hub motor bike?? Which would you recommend?

Have you ridden one? They seem too small for anyone above average size. Plus I'm too spoiled by silent hubmotors to put up with the sound of a high rpm motor unless high rpm is only at high speed...ie no small drive sprockets or pulleys for me. You'll learn more, can build something better (though l...
by John in CR
Sep 28 2020 12:59am
Forum: E-Bike General Discussion
Topic: Hall sensor repair..quick question
Replies: 11
Views: 312

Re: Hall sensor repair..quick question

Did you test to be sure that it's not a hall wire problem instead of the sensor? In 12 years of ebiking with many bikes I've never had a hall failure. In the early years I did heat a motor up enough to melt the halls wires up enough where they go thru the axle to melt the insulation a bit making it...
by John in CR
Sep 27 2020 5:20pm
Forum: E-Bike General Discussion
Topic: Hall sensor repair..quick question
Replies: 11
Views: 312

Re: Hall sensor repair..quick question

Did you test to be sure that it's not a hall wire problem instead of the sensor? In 12 years of ebiking with many bikes I've never had a hall failure. In the early years I did heat a motor up enough to melt the halls wires up enough where they go thru the axle to melt the insulation a bit making it ...
by John in CR
Sep 27 2020 11:58am
Forum: E-Bike Technical
Topic: Is regenerative braking really worth anything?
Replies: 104
Views: 2843

Re: Is regenerative braking really worth anything?

But cranks mounted on square tapers don't "budge", and neither do pedals that have been tightened upon mounting. But both can move enough under reversing torque to back the fasteners off, and then everything goes sideways. The remedy, if you must use fixed gearing, is to check and tighten these thi...
by John in CR
Sep 27 2020 3:16am
Forum: E-Bike Technical
Topic: Is regenerative braking really worth anything?
Replies: 104
Views: 2843

Re: Is regenerative braking really worth anything?

But when you spin the axle and it costs more to fix it than to get another motor, that feels not so good. Reversing torque does that to pedals, to cranks, and to the axle nuts of hub motors. Using a freewheel rather than a fixed gear prevents it for pedals and cranks, and using forward-only drive p...
by John in CR
Sep 26 2020 8:12pm
Forum: E-Bike General Discussion
Topic: Leafmotor project
Replies: 60
Views: 1263

Re: Leafmotor project

Hmmmm more torque myth....... AGAIN Two same motors of different wind counts do not have a) more torque or b) more speed, they both have the exact same torque and speed. Playing around with tire diameter, controller voltage and controller amps, gauge and length of battery cables and phase wires you...
by John in CR
Sep 26 2020 7:39pm
Forum: E-Bike Technical
Topic: Is regenerative braking really worth anything?
Replies: 104
Views: 2843

Re: Is regenerative braking really worth anything?

If it tested at 16.5Ah , you should be satisfied right?; meets expectations. How would you feel if it tested 15.3Ah ? How would you feel if it tested at 17.7Ah ? When I say regen is nice, I mean it feels like the latter. Sometimes it's really nice. But when you spin the axle and it costs more to fi...
by John in CR
Sep 26 2020 9:20am
Forum: E-Bike General Discussion
Topic: Leafmotor project
Replies: 60
Views: 1263

Re: Leafmotor project

...They're only equal if 1) you drive them both to saturation, and... Wrong as usual. They are the same motor and are in no way the equivalent of changes in gearing. They simply require a different combination of voltage and current for the same result. I take my earlier statement back. You don't r...
by John in CR
Sep 26 2020 8:42am
Forum: Motor Technology
Topic: Leaf / leafmotor / leafbike high efficiency 1500w motor
Replies: 1777
Views: 238717

Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

:thumb: Neat trick! At which point out of the axle do you solder on wire to the phase wires? Is your controller really close by the motors axle? The way to get maximum copper through the axle is with magnet wire. Group the strands into the 3 phases at the ends, but pass the bundle through the axle ...
by John in CR
Sep 25 2020 6:37pm
Forum: E-Bike General Discussion
Topic: Smarter Way To Be Seen - safety for electric portable vehicles
Replies: 5
Views: 307

Re: Smarter Way To Be Seen - safety for electric portable vehicles

Smarter would be not to ride at night, since it more than doubles the risk of fatality and that's just comparing night to day totals without factoring in how many fewer are on the road at night, so it's many times double the risk.
by John in CR
Sep 24 2020 7:23pm
Forum: E-Bike General Discussion
Topic: Battery Disconnect method.
Replies: 67
Views: 3140

Re: Battery Disconnect method.

https://www.ebay.com/itm/Car-Boat-Battery-Power-Isolator-Master-Disconnect-Cut-Off-Switch-12V-300A-Y2US/313223301531 To be fair, I don't trust the rating. But I'm only running it at 48V and 35A. Seems like too much power for someone like yourself, thats some good throttle hesitation to beholdenth t...
by John in CR
Sep 23 2020 11:26am
Forum: Motor Technology
Topic: Leaf / leafmotor / leafbike high efficiency 1500w motor
Replies: 1777
Views: 238717

Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

The way to get maximum copper through the axle is with magnet wire. Group the strands into the 3 phases at the ends, but pass the bundle through the axle as one circular round bundle of wire including the hall temp sensor wires which can also be thinner gauge magnet wire. I've done it several times ...
by John in CR
Sep 22 2020 7:46pm
Forum: E-Bike General Discussion
Topic: How often do you test your charger?
Replies: 9
Views: 282

Re: How often do you test your charger?

Every time. +1 I charge to quite conservative voltages 4.05V/cell and I always check voltage after the charge. I only need to charge 2-3 times/wk and when I start the charger I set an alarm on my phone to go check it and disconnect. To get to 4.2V would take over an hour additional charging, so eve...
by John in CR
Sep 22 2020 6:55pm
Forum: Motor Technology
Topic: Hubmonster teardown
Replies: 70
Views: 7651

Re: Hubmonster teardown

The diameter of the cover of the MidMonsters I have is 197mm, and the HubMonster cover is 208mm. The diameter of HubMonster's stator is 180mm, but I forget what the diameter of MidMonsters' stator is. John, what is the difference between them? is the mid monster that much less exploitable? I’m in t...
by John in CR
Sep 21 2020 12:42pm
Forum: Motor Technology
Topic: Leaf / leafmotor / leafbike high efficiency 1500w motor
Replies: 1777
Views: 238717

Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Lower throttle settings are also less efficient, as your graph shows. No, no, NO. You're looking at different conditions to the left of cruising speed where torque and power are significantly higher, so they occur for less time. They occur all the time if you use a real adult bike with full diamete...
by John in CR
Sep 20 2020 6:19am
Forum: Motor Technology
Topic: Leaf / leafmotor / leafbike high efficiency 1500w motor
Replies: 1777
Views: 238717

Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Lower throttle settings are also less efficient, as your graph shows. No, no, NO. You're looking at different conditions to the left of cruising speed where torque and power are significantly higher, so they occur for less time. The difference in efficiency at speed of 87.2% and 87.1% is small enou...
by John in CR
Sep 19 2020 9:41pm
Forum: Motor Technology
Topic: Enertrac hub motor cutting out
Replies: 24
Views: 1040

Re: Enertrac hub motor cutting out

First, don't do stall tests...Seriously nothing good can come of it. Great work on eliminating everything but the controller and motor. I never trust supposed correct wiring configs for halls/phase, and always verify correct wiring. With wheel off the ground and slowly giving it a bit of throttle, d...
by John in CR
Sep 19 2020 3:10pm
Forum: E-Scooter and Motorcycle General Discussion
Topic: Chinese Grom Clone with 8K QS Hub and Nissan Leaf G2 battery pack build
Replies: 13
Views: 805

Re: Chinese Grom Clone with 8K QS Hub and Nissan Leaf G2 battery pack build

Nissan Leaf cells need a bit of compression to get the most out of them and prevent them from swelling. Do you have all of the Nissan hardware that help you achieve even compression using bolts through the holes at the 4 corners without deforming the cans? Look up a pack teardown video to get an ide...