Vespa ciao electric conversion

Dr770

10 mW
Joined
Jun 18, 2018
Messages
23
Hello there. I am on an electric conversion build on a vespa ciao. The petrol engine is far gone so here it goes
I will be using 6384 150kv bldc, yep150 amp esc and 6s12p 18650 30q li-ion about 2.9ah each on a vespa ciao. I have some questions that i couldn't find exact answers. Actually i write this to the electro ciao tread but than i thought i can start a new tread.
1-the motor is a 36v 4500w motor(if it is true) this gives a peak of 125 amps @36v. And in theory 0.288ohm coil resistance. Does it mean that the motor will draw 24/0.288=83. 3 amp @24v resulting around 2000w? Hence VxI=P
2- I am thinking about using toothed belt without clutch.

3-i have a 6s charger so i am thinking to use 6s on a motor that is capable of 10s. I won't need 4500w any way. Any down sides besides loss of power? I will play with the gearing to get a max speed of 35km/h.
Any help will be appreciated.
Regards
 
All electronics arrived today. Its hard to belive the size of esc, quite small. The motor looks to be ok. I am sure there could be better bearings, but i belive they will do the trick for now.
I measured the coil resistance and the value was changing between 0.2-0.3 ohms since there were only 1 digit. So it's some where around my theoric calculations.
Bought some plastic parts for battery packaging, esc programming card and connectors as well.
Any help appreciated
Thank
 
Here is a picture of someelectronics. Batteries are samsung 18650 30q
 
Packing up the batteries with simle battery holders. Used bison contact adhesive which is ok to 70*C.
 
Just a quick sketch of some of the wiring.
 

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Made a charge setup with what's around. Ibax b6 can put out 2.4amps at 6s and gets very hot. So i used a small blower fan to cool it down. I had to set up the check time to 60min to start charging. Since tha battery is very large if you use smaller check time the device can not detect the voltage correctly. The initial charge was 3.41 volts for each parallel group
 
The motor looks pretty small. You might have overheating issues with that one. Getting the gearing right will be very important.
 
fechter said:
The motor looks pretty small. You might have overheating issues with that one. Getting the gearing right will be very important.

Yes i think so. But actually i am taking below link as referans. And my motor choice is slightly larger. I will be using a shunt and monitor the current and try to optimise the gearing.
https://endlesssphere.com/forums/viewtopic.php?t=44573
 
Simple servo tester-esc set up. Unfortunately my shunt display toasted in 30 seconds.
Used the programming card, just followed the directions i could find online.
I also tried hall effect twist throttle-servo tester combination but somehow it didn't work.
The motor runs fine without any weird noises. I tried to understand rpm by stupid android strobe light applications but non of them_20180813_211448.JPG seems to cover the job, at least with my phone.
 
Made some progress and the ciao is in pieces. Luckily the battery and the bldc motor fit in the place where the gas engine sits. This means there will be no extra place needed for battery and achieve a cleaner look. I used a round metal box to mock up the brushless motor.
 

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I am trying to design a motor mounting plate that will help cooling the motor and add some stiffness to the frame. The gas engine was working as a structural element so this should help a little. The plate will also include toothed belt tensioning between different sprockets
 

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Some progress.
I designed a motor mounting+cooling plate, made a cardboard template and drilled out and slotted mounting holes on the frame.
 
More on bldc speed kontrol:
As i mentioned before i am using a simple servo tester setup as throttle input, But not using e bike twist throttle. I would like to keep the stock brake levers so i will route a throttle cable to a linear potansiometer and get the voltage a output of the pot as throttle signal to the servo tester. The linear pot was 5k but the pot on the tester was 10k. Couldn't find the reason but it was difficult to set throttle off and max levels with the esc programming card.
I managed to run the system as i wish but start up was quite instable on the motor and any change in throttle was very harsh. Either settings for start up on the esc was too slow or too harsh.
So i ended up making a low pass r/c filter to smooth out the throttle transitions. It worked! 😁
You can find the details about the system in below pictures. Now i have a moderately smooth throttle.
 

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Cool build! I have a similar machine that I've spend an embarrassing amount of time tuning as an adult, before I discovered e-bikes and never looked back.. I'm following this thread curiously to see how you setup the drive line.

One of the weakest points of this machine is the belt and pulley drive train, not sure if I would want to go that route and keep using it, but mounting a motor like you intend does look interesting. Overheating the little motor could be a problem. Snapping the frame just below the tank is another common problem (I got that area beefed up after a near snap) this machine has.

I have considered just getting a big hub in a 16-17" wheel and fabricate some kind of bold on dropouts for it, but I don't have the skills or machinery for this right now. Also still actually I enjoy pedaling in moderation, but the ciao is utterly useless for that.
 
knurf said:
Cool build! I have a similar machine that I've spend an embarrassing amount of time tuning as an adult, before I discovered e-bikes and never looked back.. I'm following this thread curiously to see how you setup the drive line.

One of the weakest points of this machine is the belt and pulley drive train, not sure if I would want to go that route and keep using it, but mounting a motor like you intend does look interesting. Overheating the little motor could be a problem. Snapping the frame just below the tank is another common problem (I got that area beefed up after a near snap) this machine has.

I have considered just getting a big hub in a 16-17" wheel and fabricate some kind of bold on dropouts for it, but I don't have the skills or machinery for this right now. Also still actually I enjoy pedaling in moderation, but the ciao is utterly useless for that.

Thanks for your feedback!
I am not using the stock v belt pulleys, instead I am machining toothed belt pulley centers to match the transmission input shaft and the motor. becouse of the location of the motor the belt length will be shorter and I am going to be able to locate the battery to the place where the ICE sits. I cant buy the hub motors where I live, the only option is 250w and they have huge price tag. Actually My father has an ebike with that kind of 250w hub motor and it is not fun at all.
I am aware of the option of over heating and at the moment trying to find solutions. I have considered locating a fan propeller on the back side of the motor so it can cool itself but the space is very limited. So I am thinking about blowing good amount of air to the motor and making an aluminum big mounting plate additionally support continious fresh air flow around the motor. For the esc,place cooling fins and fan and begging this will be enough :)
Fot the strength I will machine a bracing over the center foot place which will be fastened and weld another u formed steel (3mm?) on the bottom side, (below the ICE place) bracing the left and right halves of the frame, this piece is also going to carry the battery box.
The biggest problem will be the start up with sensorless I guess. I am keeping in mind the option of keeping the pedals and helping the motor on startup, just 1 or 2 revolutions will be enough I think.

I would love to hear more about your past experiences.

Thanks.
 
Ah well no 250w is not much fun, I was thinking more along the lines of a ready to go wheel, 3-5kw imported from china. The frame would be so hollow and empty without a motor, it could be filled with loads of batteries and controller instead. Putting batteries in place of fuel tank and a big ugly china controller in the motor compartment would be ok.

I won't build it due to other requirements I have, I need to be able to bring the battery inside over night at winter and riding a powerful ciao at winter is a pretty scary experience.. Brakes are awful. Studded tires are hard to come by for those wheels. And its bloody cold just sitting still :) Would make a nice summer ride tho.. hm..

Good that you're not reusing the original belt 'n pulley. They are a good and cheap solution for the rated 30km/h but at 50-70km/h all that stuff wears much faster and it becomes something highly unreliable. Don't even think about the variator setup, that stuff is even weaker.
 
knurf said:
Ah well no 250w is not much fun, I was thinking more along the lines of a ready to go wheel, 3-5kw imported from china. The frame would be so hollow and empty without a motor, it could be filled with loads of batteries and controller instead. Putting batteries in place of fuel tank and a big ugly china controller in the motor compartment would be ok.

I won't build it due to other requirements I have, I need to be able to bring the battery inside over night at winter and riding a powerful ciao at winter is a pretty scary experience.. Brakes are awful. Studded tires are hard to come by for those wheels. And its bloody cold just sitting still :) Would make a nice summer ride tho.. hm..

Good that you're not reusing the original belt 'n pulley. They are a good and cheap solution for the rated 30km/h but at 50-70km/h all that stuff wears much faster and it becomes something highly unreliable. Don't even think about the variator setup, that stuff is even weaker.
Actually I am not thinking to go beyond 40 km/h since my wife will be riding it mostly and I have another ICE ciao and know the limitations of the moped, they are very instable at speed not designed for that.
I checked the prices of the hub motors around 3-5 Kw and they are quite pricey compared with my 70$ 6384. Additionaly I dont like the look of the hub motor on ciao. I want to keep it as close to original as possible. The weather never gets low 10 degrees celcius by the way.
 
Power controller arrived today. I am using 75mV 100A shunt and the display below. It has alot of functions like voltage/current alarm, total energy display and so. But there is only 1 button to setup and almost no instructions 😔
Didn't have the time yet to solve this puzzle
 

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