E-gebe

[split_yer_wig]

sweet........but im gonna check your progress on the e-motor.........like i said.............the possibilities are better on the electrical side of things.................i wonder why no one bothered to try this before..............................if it ends up working well for you im in like flynn.............................****,im thinking of hooking up a powerfull 1000 watt or even HIGHER engine and forgetting about front hub kits with gas back end hybrid stuff......just wheel into work and plug in the breakroom......................................maybe even offer to build everyones bikes at work for lunches and afterwork beer.....i know alot of them will want one too.....i just gotta do more research on electrical stuff.......................and of course battery technology

 

[split_yer_wig]

updates bro?..............i have a feeling that this can be alot more powerful than a hub.....not just because you can install more powerful motor but because the pully/belt system offers more torque (or so i would guess)..............you may be onto something here

 

[augidog]

i've been watching this with great interest...as soon as i saw the subjectline, it made perfect sense

 

[MX21]

No update yet. I sent a support request to the manufacturer of the speed controller to find out the best settings for a high-torque application like this. They haven't responded yet. I may just do some experimenting tonight with some of the settings like motor start power, advance, PWM rate, etc.

I'm also working on an instrument panel. My other hobby is radio-controlled airplanes, with experimentation in UAV applications. I have a board I built that uses a GPS to log speed and position, plus current, and voltage to an SD card. I've modified my current sensor to handle higher currents. This way I'll have a live display of current, voltage, watts, avg watts, speed, climb rate, odometer, etc., plus a recording of the entire trip.

MX

 

[MX21]

Took it out again tonight after tweaking a couple of the speed controller settings. Seemed to work a little better. Then while coasting in the driveway, the motor started making noise. Looks like a magnet came loose. I'll have to see about getting the motor fixed or replaced.

MX

 

[MX21]

Am I overworking the motor? I only peaked at about 53 amps today. But is the torque too much?

The drive ratio using the 17 tooth pinion on the motor and the 266 tooth GEBE ring is about 16:1. Am I require too much torque from the motor? Would it be better to add another reduction stage and use a higher kV motor?

Which is better: use a low kV (171) motor with 16:1 drive ratio, or a higher kV (340) with 32:1?

Or maybe this motor had problems to begin with. ?

 

[Alaskavan]

MX, that other guy who is working on a similar project is (I think) Recumpence. He has a thread about the build here: http://www.motoredbikes.com/showthread.php?t=10497 . Maybe you guys should be comparing notes.

 

[split_yer_wig]

wondering if titan system would be better if using electric motor.......im thinking a little less torque

 

[srdavo]

Am I overworking the motor? I only peaked at about 53 amps today. But is the torque too much?

The drive ratio using the 17 tooth pinion on the motor and the 266 tooth GEBE ring is about 16:1. Am I require too much torque from the motor? Would it be better to add another reduction stage and use a higher kV motor?

Which is better: use a low kV (171) motor with 16:1 drive ratio, or a higher kV (340) with 32:1?

Or maybe this motor had problems to begin with. ?

electric motors produce a "bunch" of low-end torque.

coupled with a 16:1 gear reduction, thats a "whole bunch more" torque.
(also resulting in a lower top speed.)

what is your motor's max. rpms?

on your test rides....what speeds are you achieving?

 

[MX21]

electric motors produce a "bunch" of low-end torque.

coupled with a 16:1 gear reduction, thats a "whole bunch more" torque.
(also resulting in a lower top speed.)

what is your motor's max. rpms?

on your test rides....what speeds are you achieving?

The motor is rated at 171kV and up to 12s lithium battery (44.4v), so rpm at max volts is about 7600 in theory. I get around 30 mph on level ground, which seems to agree pretty close with calculations.

I got this from the motor speed controller support (Castle Creations):

You are correct, under load the ESC is loosing sync with the motor. Low ‘motor timing’ helps
 with this but as you are already at low there is no help here. The problem is, with these large, low Kv 
outrunners when you put them under too much load the stator iron saturates and becomes a dead short 
to the ESC. Of course, when this happens the ESC can no longer accurately read the back EMF from the 
motor and looses sync and you can get no more power or the motor stops suddenly. Iron saturation is 
the bugaboo in the closet with outrunner motors.

I'm not sure I understand this. The meter shows a max of about 53 amps, yet I'm overloading the motor? The motor does get pretty hot, but I was wondering if that's due to the loss of sync. Maybe the current is jumping way up when out of sync, but only periodically and the average current is still low.

MX