A Very Very Low Cost Electric Bike from Pakistan

[numberonebikeslover]

Just make sure each commutator segment has a connection.

If you have a short between strands in a winding, it will be hard to detect by measuring resistance. A shorted turn will act like a shorted secondary in a transformer and result in excessive heat and current draw. Once you get it all back together, run the motor with no load and measure the current. Hopefully it will be close to what it was originally. This is the best test.

Also measure resistance between the commutator segments and the motor shaft. There should be no continuity there (infinite ohms). If the insulation of the wire gets cut on the edge of the iron, it can short out.

The commutator gets very hot during normal operation. I'm not sure what the temperature rating of super glue is, but it could fail at high temperatures. Winding some thread around the segments is not a bad idea, just use something with a high temperature rating. Nomex or Kevlar are the best, silk is also excellent. Polyester is not good. Cotton is between.

Sir, It is always a great deal of learning from your comment and therefore, I await it desperately. Thank you very much for the time you take to read my posting and then take precious time out of your busy life and post a comment.

Yes I have tested; every commutator segment has a connection. Last time it was very painstaking for me to open the assembled motor and found out that one segment was not connected. So I learned this lesson the hard way.

I am sure that there will be no sort between winded strands for this very reason I bought the new wire and removed the old one.

No load current of the motor I will check after motor being assembled together.

The short of any wire at any point with the motor shaft; I am sure there wont be because there is plastic / ceramics insulation on entire motor and a very good one. But I will check to make sure there is no short.

This is true that commutator will get hot and only the glue wouldn't hold the poor repaired thing together. I thought it over and decided to use something which is called as (Mochi Taar) in our native language. (Mochi means Cobbler and Taar means segment). It is a kind of segment used by the cobblers to sew and mend the shoos and foot ware. It is a mixture of silk and cotton and although being thin just a single strand is not breakable with bare hands.

Thanks again. Yours Respectfully; M.Naeem Zahid

 

[numberonebikeslover]

If available, dental floss is incredibly strong and will not stretch. The unwaxed variety will accept glue better.

I will look for that if i could find it here. Thanks for the suggestion.

 

[numberonebikeslover]

Ok got two options to go with so one was a silk thread and the other I mentioned was Mochi Taar mentioned earlier. Tested both and found the Mochi Taar a lot lot powerful. So I winded 7 straps around and knot them then put super glue on it and it became harder and firm then mare plastic. See the pic for details (A red strip around commutator is the stuff).
I put more insulation on the copper winding to ensure good insulation and packing of any lose wind so I will wait for a day more to assemble the whole thing together.

Till then bye bye.

 

[fechter]

Mochi Taar looks good. One time I tested a silk string by holding it against my hot soldering iron. I couldn't see any obvious effect other than a color change. Most synthetics will just melt.

I recommend testing commutator against shaft to make sure the wire insulation isn't cut by the edges of the iron laminations during winding. I've seen this failure a few times before. Normally the motor has some paper insulation inside the slots that protect the wire from rubbing on the iron.

Extra varnish or whatever insulation around the windings is good to prevent the strands from vibrating or rubbing against each other which could lead to a failure later.

It's a lot of work to rewind a motor. I've done it a few times.

One more thing:
It is good to try to balance the armature before assembly. If you can set it up so the shaft is supported by a pair of very smooth flat objects, you can roll it slightly to see if there is a heavy side. Sometimes the bearings are loose enough to just support the bearings. If one side is noticeably heavy, you can try to add weight to the opposite side to balance it. Some people use epoxy glue to add weight. I used some silicone glue, since it can withstand very high temperatures. You may also be able to wedge some object into the slots to add weight. Typical 'keepers' are made of Nomex paper, but you can find a substitue. You need something that is non-conductive and can withstand high temperatures. Don't worry too much about the balance, but if it is really bad, the motor will vibrate excessively when running and it causes energy loss.

 

[Cyclebutt]

THIS is what Endless Sphere is all about. love it!

 

[numberonebikeslover]

I recommend testing commutator against shaft to make sure the wire insulation isn't cut by the edges of the iron laminations during winding. I've seen this failure a few times before. Normally the motor has some paper insulation inside the slots that protect the wire from rubbing on the iron.

There is no continuity between commutator and the motor shaft.

Extra varnish or whatever insulation around the windings is good to prevent the strands from vibrating or rubbing against each other which could lead to a failure later.

Yes of course; I waited one more day for extra varnish to dry. After office I tend to finally put the motor together

It's a lot of work to rewind a motor. I've done it a few times.

This is probably my 5th time to wind this very motor. Yes indeed it is a lot of work but now I have gotten used to it. Only this time it was more tougher for inserting more and more wire.

One more thing:It is good to try to balance the armature before assembly. .......Don't worry too much about the balance, but if it is really bad, the motor will vibrate excessively when running and it causes energy loss.

I will check this today when I come back from the office. Thanks for the advice.
Respectfully Yours; Naeem

 

[numberonebikeslover]

THIS is what Endless Sphere is all about. love it!

Good day to you sir, The most loving and caring place on the web where we all are one big happy family. It is a big example for the rest of the world for living with peace and harmony. Sincerely Yours; Naeem

 

[numberonebikeslover]

Dear All;

Greetings from Peshawar, Pakistan.

I took a last look at the rotor and found that still the extra varnish I put the last time was still not as dry as I thought it would be. I spent the entire day in the office and now there was no sun to heart the thing up slowly. I thought of a plan to heat it up slowly as it would be in the sun. I run through the commutator (at the points where the brushes would make a contact) some Dc voltage about 10 volt for a while. After some time I noticed the rotor slightly warm but not hot enough for it was in the sun light. So I increased the voltage to 12 volt through a 100 amps battery and it turned warmer in a minute time. So I carefully watched it and did not leave it as such for safety reasons. In little time (about 1.30 hours) all my room was full of varnishes smell all around. Finally after being dried I decided to finally fit it into the motor.

One thing that I was worried about was that I had changed the position of the commutator and therefore, I have also to do something about the position of the brushes as well. It was easy, I removed the front shaft washers and the shaft went a little further in the motor stater and its all done. I remember that back plat has bearing's collar and it also holds the rare shaft of the motor where the commutator exists. The shaft went forward a bit so it also needs some amendment. I pressed the bearing collar a bit further inward and used little hammering action and it was a perfect fit. I wish it was day and I had made a video of it would have explained a lot better but it is night and dark and my camera wouldn't work good.

Fitted the motor in the bike but did not put the chain in and gave it voltage to check the no load amps drawn. I have this small digital meter which is not that efficient but gives me some track of statistics.

On attaching the motor with a 12 volt 100 ah battery the motor drew .5 amps
on 36 volt it drew .7 to .8 amps
on full throttle 57 volt the meter is giving funny reading some time it reads 2.5 some time it reads 1.7 and keeps changing between these two values. May be the meter's fault or what?

I have noticed that motor's shaft is kind of sluggish to rotate by hand. May be the bearings will find time to adjust in the new fitting and therefore it is a bit hard and may be that is why it is drawing some amps. I feel clearly that the torque is enormous even on 12 volt it is not possible at its low rpm to stop the shaft by bare hands. When I applied force to stop the motor on even 12 volt it drew 1.23 amps on no load it was although .5 amps.

Any way today after office I intend to put the chain and take it for a spin.

Any feedback will be highly appreciated.
Respectfully yours
Muhammad Naeem Zahid

 

[fechter]

The test sounds successful. If there was a shorted winding, the current would be much higher and the motor would get hot fast. Not sure what would cause the reading to jump, but like you say, it could be the meter. I assume the motor sound did not change with the readings.

I know what you mean about the varnish. It soaks into the windings and takes forever to dry. Last time I did that, the first time I ran the motor, all the excess varnish sprayed off the motor when it was spinning and varnished the magnets nicely.

 

[numberonebikeslover]

The test sounds successful. If there was a shorted winding, the current would be much higher and the motor would get hot fast. Not sure what would cause the reading to jump, but like you say, it could be the meter. I assume the motor sound did not change with the readings.

I know what you mean about the varnish. It soaks into the windings and takes forever to dry. Last time I did that, the first time I ran the motor, all the excess varnish sprayed off the motor when it was spinning and varnished the magnets nicely.

The motor sound never changed with the change in meter reading, infact due to more number of winds of copper than before the rpm has reduced on 60 volt and the motor is a bit quieter then before. Moreover, the torque has increased even at reduced rpm it is so powerful that it makes me smile.

After putting back the chain I run the motor to see the tire spinning while standing the bike on double stand and let the wheel spin freely. I tried to hold the tire against wood it would show so much torque at half the throttle.

Something funny happened all of a sudden; After turning the switch off I spin the wheel in reverse direction to see if all the gear reduction works fine, the motor got stuck and wouldn't run to any direction now. I was scared to death for it could be a broken magnet, a snapped copper wire any thing. My heart just sank and due to low blood pressure I could not do any thing with it. To detach the motor and open it apart again would need a lot of time and I was not feeling well therefore, I had my dinner and praying Allah I went to bed and left it as such for the next day.
Wish me luck guys.
Naeem

 

[fechter]

I hate it when that happens.

Hopefully it's something simple like a stuck brush.

 

[numberonebikeslover]

I hate it when that happens.

Hopefully it's something simple like a stuck brush.

Thanks God! it was just what you said earlier. A big load of varnish all splattered in the motor and behaving like chewing Gum. Took out the motor and washed the stater containing magnets with with hot water with washing powder. I came to know that there were a lot of iron dust inside which became visible I took it out using my fingers and then piece of cloth. the amount of varnish was so much that it seemed like the entire varnish was out in the motor. I looked at the rotor. there was no trace of any varnish. So I thought may be it needs some dip in the varnish. So I did it again; poured some varnish on it and the same way gave the commutator some voltage to heat up just a little and then put it infront of a computer fan to cold and then heat it up again for few days till I am sure that all the varnish is dry. Only then I will assemble the whole thing together.

I am really happy that nothing like a broken magnet happened.

Thanks for your concern.
Yours Respectfully
Naeem

 

[numberonebikeslover]

A wonderful idea;

Till tomorrow the rotor would be dried I guess. Before fitting it back in the stator I would put it on a drill and spin it so that if there is still some varnish in hidden form should come out due to centrifugal force but I am sure that there will be non.

P.S. Started a new thread here: http://endless-sphere.com/forums/search.php?search_id=egosearch

Mod Edit: I think this is the thread Naeem meant:
http://endless-sphere.com/forums/viewtopic.php?f=28&t=44774&p=651979#p651979

 

[fechter]

A wonderful idea;

Till tomorrow the rotor would be dried I guess. Before fitting it back in the stator I would put it on a drill and spin it so that if there is still some varnish in hidden form should come out due to centrifugal force but I am sure that there will be non.

Good idea. I was going to suggest that. Once you spin the rotor, any excess liquid will fly off and what's left will dry much faster. Just be sure to do it inside an old cardboard box or bucket as it can be very messy.

You don't need too much varnish, just enough to stick the wires together so they don't move.

 

[numberonebikeslover]

Good idea. I was going to suggest that. Once you spin the rotor, any excess liquid will fly off and what's left will dry much faster. Just be sure to do it inside an old cardboard box or bucket as it can be very messy.
You don't need too much varnish, just enough to stick the wires together so they don't move.

After putting the rotor on 12 voltage the rotor heated up and felt like its been put in the sun and it dried up all the varnish. After spinning the rotor on the drill I found no excess liquid and it was good to go for fitting it back in the motor. I also took the time to put some mobile oil in the bearings which made the motor so soft to rotate with just a little bittle cog due to magnetic effect and that is normal. The motor is awesome so much torque I have never experienced. Although the motor is running at a little lesser RPM but it is such a powerful motor now. I took the bike for a spin and it was such a nice feeling I just can't explain in words. I decided to put it to the test of climbing a hill. I live outside Yakkatoot gate. from there a hill descends to Kohati gate and it is proximately a 35 to 40 degree hill but a short one which may be about a 100 meter. The bike even did not slow down while climbing it. Then I checked the temperature of the motor and mosfets found them just warm. Then I put the bike in higher speed gear and tried the hill again. Only this time the motor sound felt like motor is doing some effort and the speed reduced a little on while climbing the hill. This time the motor got just a little hot like it was lying in the sun. I am sure now due to increased efficiency the bike will cover greater distances then before. Due to pukert effect the battery will last longer I guess.

Naeem

 

[numberonebikeslover]

Forgot to mention one thing;

The bike was about the fell off but I grabbed and did not let it go. It happened when I put it on the double stand (doesn't have a single side stand) I was in a hurry and did not notice the ups and downs in the floor. I measured the bike in a side stand position by putting bricks underneath and letting it lean that way and figured out the point to put the stand. I went to the market and bought a single side stand for Rs. 200/-. The problem with the stand is that the large one was a lot larger and the small one was a little smaller than my measurement. So I bought the smaller one and decided to extend it a little further by welding a piece of metal with it. It is night so I am not able to take good pictures. Tomorrow I will take pictures and post them.

 

[Harold in CR]

Glad to hear you have had success. 8) 8)

 

[numberonebikeslover]

Hi everyone,
Here are the pictures of the motor when it was stuck and I opened it. The splattered varnish could be seen on the rotor and in the stator magnets.
Naeem

 

[numberonebikeslover]

Assalam-O-Alaykum everyone; (this is our way of saying Hi meaning May God shower His blessings upon you)

I had such a wonderful ride experience all weekend. Also fixed the side stand and found out that this one is meant for a lot lighter bike and can't support mine. So, I did a lot of welding on the base to strengthen it and now it is strong enough to support the bike. The bike looks awesome on its side stand. Seems like an arrogant lady posing for her boyfriend in a sexy style (he he he). I sometime feel like she is talking to me and saying thanks for putting my so much energy and time in her. She is rather becoming a complete person in my life now. I am feeling like every creator fells in love with its creation. That is what happening with me.

Does any one feel like that about theirs or is it me just getting a screw lose in my head?

While cruising in the streets of my neighbourhood I almost had an accident over a bump which I could not see clearly. I noticed that the handlebar was blocking my way so I bent the handlebar a little more (it was very difficult task for I had nothing special to bend a pipe). Now it is more comfortable and I can see the road more clearly.

Sincerely
Naeem

 

[Solcar]

Naeem, cool!

 

[fechter]

Seems like an arrogant lady posing for her boyfriend in a sexy style (he he he). I sometime feel like she is talking to me and saying thanks for putting my so much energy and time in her. She is rather becoming a complete person in my life now. I am feeling like every creator fells in love with its creation. That is what happening with me.

Does any one feel like that about theirs or is it me just getting a screw lose in my head?

Anyone who spends a significant part of their life building a creation has similar thoughts. Likewise, when it breaks, it feels like a loved one suffering an illness.

Glad to hear you have it running. With the new winding, the motor current should be less, which will help the commutator and brush heating.

Time to start looking for old laptop batteries.

I remember long ago a guy built a 'hybrid' pack that used both lead-acid and lithium batteries in parallel. The lead-acid could supply bursts of high current, while the lithium would provide most of the energy. Typical laptop cells are not good for high discharge currents. If the lithium pack is big enough, it can supply the full current, but they should generally be limited to 1C-2C discharge rate.

 

[Cyclebutt]

I remember long ago a guy built a 'hybrid' pack that used both lead-acid and lithium batteries in parallel. The lead-acid could supply bursts of high current, while the lithium would provide most of the energy. Typical laptop cells are not good for high discharge currents. If the lithium pack is big enough, it can supply the full current, but they should generally be limited to 1C-2C discharge rate.

Interesting. I have found this thread most instructive. Many thanks to ALL involved!

 

[numberonebikeslover]

Time to start looking for old laptop batteries.
I remember long ago a guy built a 'hybrid' pack that used both lead-acid and lithium batteries in parallel. The lead-acid could supply bursts of high current, while the lithium would provide most of the energy. Typical laptop cells are not good for high discharge currents. If the lithium pack is big enough, it can supply the full current, but they should generally be limited to 1C-2C discharge rate.

What I understand from using lead acid batteries their charge gets full on 14.7 to 15 volt (mostly depending on the charging current). Considering two situations:

1) 4 cells in series and charging them as a 12 volt pack connected parallel with a 12 Ah 12 volt battery with HVC at 14.7 to 15 volt; for Li-Ion 15/4 = 3.75 volt per cell which is not near full as it needs to go as high as 4.2 volt per cell to fully charge it.

2) 3 cells in series and charging them as a 12 volt pack connected in parallel with the same lead acid battery with HVC at 14.7 to 15 volt. In 3s situation in case of Li-Ion 15/3= 5 volt per cell which is highly unsafe for a lithium Ion cell.

Situation 1 is a bit safe but not assuring the full charge. I would love to do this kind of hybrid pack for more energy but I heard somewhere I don't remember where that combining two chemistries is not advisable.

One thing just came to my mind; Combining both chemistries will ensure the safety of Li-Ion pack and the Lead acid pack will act like a buffer and would not let the Li-Ion pack over load or over charged.

I would really appreciate a little help in sorting out the configuration of lithium Pack in combination with Lead acid pack.

Yours Respectfully
Naeem

 

[numberonebikeslover]

Interesting. I have found this thread most instructive. Many thanks to ALL involved!

This is what families are all about. All ES members are a big happy family, every member helps the other without any selfish interests. I am sure that the role of ES in promoting Electric Vehicles in the communities all over the world will certainly be written in Gold.
Yours Respectfully;Naeem

 

[FfredDRredD]