Author Topic: new kit problem  (Read 8606 times)

Offline tartosuc

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new kit problem
« on: August 04, 2008, 11:54:18 AM »
Hi

i just purchased a 36v 500w front motor kit.

when I accelerate I get a loud noise that quiets down when up to speed.

I also have no power at all going uphill

any idea what can cause my problem?

se below video to hear the problem...

thanks

http://www.youtube.com/watch?v=scIbcDPoARc

Offline biohazardman

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Re: new kit problem
« Reply #1 on: August 04, 2008, 07:16:40 PM »
Can't get the vid to play on my system.  From my experience with your explanation it could be loose spokes.  They need to be tightened often until they are done stretching. They make allot of noise till you get up to speed then quiet down.  The hill problem could be from not having batteries that can give the current draw needed or loose electrical connections. There may be bearing problems if you did not install some washers to fill the gap between the frame dropout and the supplied, but to short spacer, on the wired side of the motor.  Many other things could be wrong but these are not to difficult to check.

Offline tartosuc

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Re: new kit problem
« Reply #2 on: August 04, 2008, 07:29:19 PM »
Can't get the vid to play on my system.  From my experience with your explanation it could be loose spokes.  They need to be tightened often until they are done stretching. They make allot of noise till you get up to speed then quiet down.  The hill problem could be from not having batteries that can give the current draw needed or loose electrical connections. There may be bearing problems if you did not install some washers to fill the gap between the frame dropout and the supplied, but to short spacer, on the wired side of the motor.  Many other things could be wrong but these are not to difficult to check.

thanks for the reply

spokes are good for shure, I've re-tighten some but anyway  it is not  a spoke noise (I used to be a bicycle mecanic )

I did not add spacer but i've been able to tight down the bolt correctly..i will double check that and add some spacers to see

as for batteries, I thought of  batteries not supplying enough but I thought regular alarm system sla 17 AH batteries should be good for that?(we see all kinds of kits setup with them).
I will double check all my electrical tonite.

i'd like to know more of what it could be..i studied electronic a long time ago, I still have some knowledge but would need guidance...
« Last Edit: August 05, 2008, 12:35:46 AM by tartosuc »

Offline philf

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Re: new kit problem
« Reply #3 on: August 05, 2008, 01:12:06 AM »
I can't make out anything untoward from the audio that accompanies the video link you posted.

The slight "stuttering" sound I can identify when you're accelerating (uphill, I think) near the beginning sounds like the sound you hear when the system is choked for power.  I've experimented with a variety of batteries, and in some test scenarios I've heard the same sound when either my batteries couldn't deliver what was being asked of them, or if I introduced additional wiring (as when I was playing with a "Watts-Up" meter) which included sections that were of inadequate guage.

I only have experience with the rear-wheel kits, and all of my wire runs are short - the batteries and controller live at the back, as well.  The harnesses I've built to power everything are overkill...  Very flexibile, stranded, 10 guage (because I had it handy) between the batteries and the controller. I can tell you, though, that batteries make a difference.  I get long run-time out of my NiMH packs, but they also exhibit the kind of stuttering I detect in your video when really pressed.  My SLAs don't stutter when freshly charged, but will being to exhibit that behaviour when they hit about 20% depletion.

Are you sure your expectations aren't too high?

If you have a GPS, or other device that can give you a reasonable idea of speed, you should be able to observe a maintained speed of 26 to as high as 30 km/h without pedaling - on level roadway with no wind.  If the bike continues to "stutter" and doesn't even come close to this, there is something else amiss.


Offline tartosuc

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Re: new kit problem
« Reply #4 on: August 05, 2008, 01:55:14 AM »
I can't make out anything untoward from the audio that accompanies the video link you posted.

The slight "stuttering" sound I can identify when you're accelerating (uphill, I think) near the beginning sounds like the sound you hear when the system is choked for power.  I've experimented with a variety of batteries, and in some test scenarios I've heard the same sound when either my batteries couldn't deliver what was being asked of them, or if I introduced additional wiring (as when I was playing with a "Watts-Up" meter) which included sections that were of inadequate guage.

I only have experience with the rear-wheel kits, and all of my wire runs are short - the batteries and controller live at the back, as well.  The harnesses I've built to power everything are overkill...  Very flexibile, stranded, 10 guage (because I had it handy) between the batteries and the controller. I can tell you, though, that batteries make a difference.  I get long run-time out of my NiMH packs, but they also exhibit the kind of stuttering I detect in your video when really pressed.  My SLAs don't stutter when freshly charged, but will being to exhibit that behaviour when they hit about 20% depletion.

Are you sure your expectations aren't too high?

If you have a GPS, or other device that can give you a reasonable idea of speed, you should be able to observe a maintained speed of 26 to as high as 30 km/h without pedaling - on level roadway with no wind.  If the bike continues to "stutter" and doesn't even come close to this, there is something else amiss.



thanks for the reply

the wheel only stutter when I start accelerating and then it get steady...it looks like i'm getting around 30 km/h on flat.

the problem really comes uphil as soon as there a hill the bike simply don't climb and I can see the battery gauge go to red...i dismounted from the bike too see if at least it will climb on its own weight and it does not even do that,,, I was expecting to pedal assit the bike going uphill, wich I tried but assist was non existant a that point... when I push down on the fork standing still in my basement I can make the wheel stops fairly easily and I can measure a voltage drop from 39 top 34v when I do...

i've been told that this motor had some good torque but I feel something is not working right here. if that what i'm supposed to get for perfomance then yes I must say i'm a bit dissapointed and I was expecting more.  The whole purpose of building that bike is to use it to go t work and I have that one uphill to do at the end..not too steep but steady for 700m....



I've checked all my connections tonite, everything is fine..my cable run from the batteries to the controller is on the long side but I used 10 guage wire to prevent problems (compare to 14 guage that that comes with the kit)

I will keep on doing some testing...any other ideas are welcome.

Offline ahend

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Re: new kit problem
« Reply #5 on: August 05, 2008, 10:08:46 AM »
If your wheel turns freely by hand when disconnected from the controller, indicating the absence of any mechanical binding, the noise could be created by a timing issue. Perhaps the phase power is not being applied correctly, or is diverted, causing the phases to fight one another and cancel output torque. If you can hold back the motor power as you say, there is something definitely wrong.

You might take a closer look at your hub motor. Measure the resistance of the phase windings through the three power leads. I'm not sure of the winding connections to the phase leads but if it's a "Y" configuration, any two leads should be showing the resistance through two series connected windings. If it's a delta configuration, any two leads will show the resistance of a single winding. Regardless of the connection layout, there should be some degree of consistency between all pairs.

Try powering your hall sensors (the smaller gage red and black wires) with a separate 5v supply and measure each hall sensor output voltage (the three remaining smaller gage wires) to the 5v ground as you slowly spin the wheel. You should see a consistent voltage change as each of the rotating permanent magnets pass over.   
« Last Edit: August 05, 2008, 09:21:03 PM by ahend »

Offline tartosuc

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Re: new kit problem
« Reply #6 on: August 05, 2008, 12:01:30 PM »
If your wheel turns freely by hand when disconnected from the controller, indicating the absence of any mechanical binding, the noise could be created by a timing issue. Perhaps the phase power is not being applied correctly, or is diverted, causing the phases to fight one another and cancel output torque. If you can hold back the motor power as you say, there is something definitely wrong.

You might take a closer look at your hub motor. Measure the resistance of the phase windings through the three power leads. I'm not sure of the winding connections to the phase leads but if it's a "Y" configuration, any two leads should be showing the resistance through two series connected windings. If it's a delta configuration, any two leads will show the resistance of a single winding. Regardless of the connection layout, there should be some degree of consistency between all pairs.

Try powering your hall sensors (the smaller gage red and black wires) with a separate 5v supply and measure each hall sensor output voltage (the three remaining smaller gage wires) to the 5v ground as you slowly spin the wheel. You should see a consistent voltage change as each of rotating permanent magnets pass over.   


thanks for the reply.

i'm not too familiar with theses parts as it is my first hub motor and first electric bike project...any more details on what they look like and where to make the measurements would be welcome.  otherwise I will try to figure it out.

anyone has a wirering diagram of this thing?(motor and controller) nothing came with the kit and the only diagram I could find on the net are for regen controllers...

Offline ahend

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Re: new kit problem
« Reply #7 on: August 05, 2008, 02:43:03 PM »
Here is a section of the connection image provided on the Golden Motor website.
The phase windings are sequenced with current from the controller to provide torque. The hall sensors provide positional signals to the controller so it knows when to apply current, and to which winding.
« Last Edit: August 05, 2008, 02:47:26 PM by ahend »

Offline biohazardman

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Re: new kit problem
« Reply #8 on: August 06, 2008, 12:35:05 AM »
I agree with the others if not a battery problem then I have heard of others that had problems with the hall sensor connector.  The male part of the spade terminal is very loose in it's seated position and may bend over or slide to the side instead of connecting with it's female counterpart when the connector is pushed together. Just one more thing to check for anyway. Good luck.
« Last Edit: August 06, 2008, 12:52:32 AM by biohazardman »

Offline Dave

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Re: new kit problem
« Reply #9 on: August 07, 2008, 04:01:20 AM »
I couldn't really make out your problem from the video -- very dark -- but it sounds a little like a problem I had when one of the phase winding connectors on mine was loose. With no load the wheel spun up just fine, but it had no torque under load. It would go ok, but noisily and slowly, on flat ground, but hills would kill it. All the wires in that connector looked ok from the outside, but one was just barely making contact.

Not sure if this is the cause of your trouble; the fact that you get a red light on your battery indicator suggests that one of the batteries might be weak. I'd check each of the batteries individually; if you search around this forum you'll find another thread with some good instructions for load testing batteries.

Offline e-lmer

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Re: new kit problem
« Reply #10 on: August 19, 2008, 07:08:42 AM »

I am using the same kit.

I live 5 miles and 600 vertical feet from work.

On the way home, going uphill, with a fat 230lb man on
the bike the 500 Watt motor will not pull me home.

When the motor gets loaded near 500 Watts (around 14Amps)
the motor begins vibrating as the sensors request more current
than the controller (and the wiring) can supply.

This is normal, and means you are coming close to damaging
things.  I bet your power LEDs dim too.

The supplied battery cable is a standard computer cord
rated at around 8 amps.  If you check, the cables are getting
warm and the motor is starting to heat up.

This also sucks the juice out of your battery and converts it to heat.

When I ride, I listen to the motor and if it is 'buzzing' I back off the
throttle and pedal more.  This gets me home and helps me lose some
of the extra weight I am carrying. :)

I am also planning on upgrading to the kW motor at 48V because
I want to carry groceries up that hill too.