MY1018 mid-drive build

This my build with MY1018 motor:









This mid-drive system is similar to Vivax Assist so when motor is running it all the time moves with crank (so I can not use the motor without pedaling), but when I pedaling, the freewheel on the left side disconect crank from the sprocket wheel so the sprocket wheel, the chain 219 and the motor is not rotating and there is no any drag. This system is suitable for "active" pedaling bikers. I use 36V version of MY1018 motor together with 12S Lion battery and the crank cadence is around 80 - 90 rpm, that is very pleasant. In this combination the maximum power of motor is around 650W, but how I can observe in wattmeter, the power of motor (and Amper consumption) mainly depends on my actual gearing on derailleur - longer (harder) gearings = more Amps) and vice versa. My normal consumption is around 4 - 6 A (200 - 300W power), but with my big human power assist. There is no any heat issue with motor.

450W Brushed MY1018 motor may seems very "prehistoric" traction unit, but has some very nice features: It is cheap, it is very leightweight (around 2,2 kg), the controller for that motor is also very cheap and simple and this motor can be tuned to 600W (with no heat issue when is proper geared down). I have used sucessfully this motor in my other electric bike projects. The only drawback of this motor is sound of its gearbox (with straight cog wheels) that is similar to gas turbine... but I like it anyway.

Like primary chain I use very robust (but expensive) 219 chain that has small segment module so you can achieve better gear ratio and also this chain manage big moment from geared motor. The freewheel is ACS screwed into left crank. On the right side I use 1 x 8 gearing system, because bike chain for 8 gearing system is significantly wider than for 9 or even 10 gearing bicycle system and is better for mid-drive. The controller is hiden under the seat. The motor holder is made from Aluminium. I use thumb a accelerator on left side on the handlebar.

I use this bicycle with my own 12S6P battery located in backpack, because I like this configuration for very lightweight feel. The Bike without battery is really very light...

Very nice setup. This is similar to an ongoing project I have going, but keeps getting put on the back burner. The LIFT-MTB system uses this motor with a right side dual freewheel at motor and crank with excellent results. I think it is a very good option for the pedaling off-road MTB rider that just wants a some extra boost now and then. I have a couple quick questions for you:

1) Is your MY1018 a newer model with helical-cut gears or the noisier old style straight-cut gears? (You mention straight-cut and a little noisy, but I thought all the newer MY1018's had the quieter helical-cut gears)

2) What type of wire connection did you use for the backpack battery pack?

3) Did you simply use a threaded right side freewheel crank arm on the left side?

IMHO sometimes less is more and just about all the electric motors out there have been around forever, it's the battery technology that has changed, and hopefully continues to improve with regard to power out and lighter weight.

Like primary chain I use very robust (but expensive) 219 chain that has small segment module so you can achieve better gear ratio and also this chain manage big moment from geared motor. The freewheel is ACS screwed into left crank.

Click to expand...

Where did you get that 219 chainring that bolts to the ACS freewheel ? did you need to modify it to suit ?

Also same for the motor cog, where did you get that to suit ? what ratio do you have now motor vs chainwheel ?

Motor and crank freewheel sprocket teeth count would be good to know as well. Thx.

Unfortunately I use old style MY1018 motor with straight gears, that is little bit noisy, but I could not find any MY1018 with helical gears at aliexpress. However in my case I could not use "helical" MY1018 because it can be used only in one rotating direction and in my setup (motor is in placed in opposite site compared to how it should be placed normally) I had to change motor rotating direction to opposite one (simply I swaped polarity from controller). To my knowledge this is not possible with "helical" MY1018 motor. I use normal straight silicon wires to connect bike with battery pack via XT90 connector. I have experienced that when something wrong happen (when fall down from bike) the XT90 connector disconnects very easily so it works also like "safe" system. 219 chainring is custom made laser cut, prepared to fit standard right ACS freewheel. Firstly I used aluminium laser cut chainring, but the wearing was very quick so now I use steel 3 mm thick chainring. It has 70 teeth. Motorcog wheel has 11 teeth and it is also custom made laser cut from steel. The left crank arm is normal original left crank arm from the bike, but is modified: I have had it made thread on this left crank arm for ACS freewheel.







In the last photo you can see tensioner, but I realized that I do not need it and that gear reduction is more quiet without tensioner. I also moved the controller from the position under down frame tube to under seat position where controller is more hidden and protected.

Sounds like you did quite a bit of custom work. I didn't know MY1018 with helical (UPDATED MY TYPO) motors aren't bi-directional? My motor is said to be bi-directional and helical geared, but I'll have to open it up and look. After all, it's form China and you never know what you are going to get. :lol:

So an additional 70 / 11 = 6.36:1 reduction plus the MY1018 motor gear reduction. What MY1018 RPM and gear reduction are you running? I see different RPMs and ratios out there and don't really know what, if anything, standard is.

I found this article at endless-sphere: https://endless-sphere.com/w/index.php/Middrive_Compatible_Gear_Reduction_Motors

Here You can see lot of information about motor MY1018. This motor with helical gears is called XYD16 and I could not find it at aliexpress so I bought "classic" MY1018 with straight gear. In article is written that motor with helical gears has recomended only clokwise rotiation. My understanding is that helical gears generate aditional axial force and you have to design bearings that will survive this force. In oposite rotating direction the axial force goes to another side, but the bearings is not designed for that. But in your setup you will have freewheels and chain in right side so the motor will go in right (clockwise) direction. Your design will be more like Cyclone design, but in my case I have chain in left side so the motor goes to opposite direction.

And now about gearing down the motor. I do not know exact Kv of the motor, but i find this:



So I estimated Kv of the motor like that:

557 (speed)/36 (I have 36 V version of this motor) = 15,47 x 7,18 (reduction ratio of the internal gearing of MY1018) = 111 Kv.

So in my case:

12S x 3,7V = 44,4V (nominal battery voltage) x 111 (Kv of the motor) x 0,75 (estimated 25% drop of motor speed under load) = 3696 rpm/7,18 (motor internal gear reduction ratio) = 515 rpm in motor cog wheel : 6,36 (70 : 11 secundary reduction) = 81 rpm in crank.

I have cyclo-computer with no cadence measurement, but you can find useful webside bicycle gear and size and cadence/speed calculator, where you can put in your bicycle gears a see your speed in different cadences:

http://www.machars.net/bikecalc.htm

Today I climb into hill with 43V in wattmetter (43V/12S = 3,58V on cell) at the lightest gear on my bike (32/34) on speed 10 km per hour that belongs 80 rpm cadence in the chart. This means that my calculations are very realistic.

Thanks for that and the links.

STICKER ON MY MOTOR STATES (C6453582):
CE MODEL: MY1018-1
Voltage: 24V
Power: 450W
Speed: 420rpm
Current: 25A

Seller claims he has them custom built to his specifications (?).

Spec's said:
Reduction: 9.78:1 (like the MY1016's with metal mount, but mine is all alloy?)
Weight: 2.2kg / 4.85lb
Motor: Reversible
Voltage: 24V or 36V

Guess I'll have to open it up and count the reduction gears to see if it is really a 9.78:1 or 7.18:1...

Thanks again for your input!

Why You don't use freewheel on the motor? When you pedalling, motor generating friction without the freewheel.

Edit. Ok, I know - freewheel on left side works in other side....

What range is on this kit?

I have my custom battery from 18650 cells (LG MG1 2,9 Ah) on configuration 12S6P = 44,4 V and 17,4 Ah = theoretically 772 Wh. Last time I chared the battery to 4.08 V per cell and end up at 3,53 V per cell and I rode 79 km in cross country mud terrain = aproximately 455 Wh/79 km = 5,76 Wh per kilometer. I think this consumption is pretty low, normaly when I go to the hill I have consuption around 4 - 6 Amps that belongs 200 - 250 W of power. I use the motor mainly like the lift when ascending and I mainly use the motor on my the lightest gear (that is 32/34) so in that case the consumption can not be huge.

This design has freewheel on the left side and connects and disconnects the 219 70 teeth chaingring from the crank so when I pedal I do not move even with 219 chain (in opposite to Cyclone design when chain moves all the time) and I do not need tiny freewheel at motor cogwheel. Because I do not have freewheel in motor cogwheel I can use very small 11 teeth cog for tiny chain 219 and achieve better ratio reduction (better than with normal cyclo chain that is used in Cyclone design). When I am pedaling the bike behaving like normal (not motorized) bike but when motor is working it is moving directly with crank arms and your legs and this system works like Vivax Assist System. Moving with your legs may be in the beginning very strange but you can get use to it and it encourage you to work (pedal) harder so that is very pro-active system. The problem may be in very hard (technical) terrain, in this condition is better classic dual freewheel system. Also this setup is obviously not good when you want use enormous power mid-drive system.

I'm looking for setup for my fat bike. Up to now I used cyclone 1680W in other bike. It is realy good, but I want rather pedal asist than poor equivalent motorcycle.
Light and low consumption batery setup. Now I live near little mountain on borderland polish and czech and I also want to lift easier fat bike uphill . Does your kit sound like this?:
https://youtu.be/i1852FkS6Dw

Yes, my kit sounds exactly like this. In promotion video (like this one) it does not sound that bad, but obviously in reality the sound is litle bit more irritating. Personaly I do not mind this sound, it remains me "gas turbine," but would be nice to have more quiet motor. I think the sound is only drawback of this motor. But I love MY1018, it is the lightest "big-reliable" motor what I know (I do not count "unreliable" chinese RC outrunners, that have a lot of issues) and that I can esaly use in bicycle aplication. It is lighter than minicyclone, it is very narrow so it can easily fit between crankarns (you do not need extra wide crank like in the case with Cyclone) and you can easily get 650 W of power from this motor when you little bit overvolt this motor.

Interestingly I am from The Czech Republic, but from the SouthWest so I ussualy ride my bike in Sumava mountains.

dingos said:

Yes, my kit sounds exactly like this. In promotion video (like this one) it does not sound that bad, but obviously in reality the sound is litle bit more irritating. Personaly I do not mind this sound, it remains me "gas turbine," but would be nice to have more quiet motor. I think the sound is only drawback of this motor. But I love MY1018, it is the lightest "big-reliable" motor what I know (I do not count "unreliable" chinese RC outrunners, that have a lot of issues) and that I can esaly use in bicycle aplication. It is lighter than minicyclone, it is very narrow so it can easily fit between crankarns (you do not need extra wide crank like in the case with Cyclone) and you can easily get 650 W of power from this motor when you little bit overvolt this motor.

Interestingly I am from The Czech Republic, but from the SouthWest so I ussualy ride my bike in Sumava mountains.

Click to expand...

Wow, this is awesome. I live near Broumovsko but in Poland. You can use some "out-sound foam" and mute this motor. I did it with cyclone gearbox and it helped a lot.

That's a brushed motor right? If so it should be reversible by changing the polarity of the positive and negative leads from the motor to the controller?

.
... Re-gearing the MY1018z motor (XYD-16 is helically geared version)

Re-volting the MY1018z motor (XYD-16 is helically geared version)

wineboyrider said:

That's a brushed motor right? If so it should be reversible by changing the polarity of the positive and negative leads from the motor to the controller?

Click to expand...

Yes, that is what i did in my design.

DrkAngel said:

.
... Re-gearing the MY1018z motor (XYD-16 is helically geared version)

Re-volting the MY1018z motor (XYD-16 is helically geared version)

Click to expand...

I know your posts about MY1018, it is very good stuff and very helpful. Thanks.

Wow, this is awesome. I live near Broumovsko but in Poland. You can use some "out-sound foam" and mute this motor. I did it with cyclone gearbox and it helped a lot.[/quote]

Thank you for your advise with noice reduction of the motor. I know Broumovskou I have been there, but in Czech side. What is your experience with Cyclone? I am thinking about that like tje next candidate for motorizing ḿountain bike. Is it more quiet? Are there any strange issues with that motor? How many Volts do you use to feed the Cyclone?

dingos said:

I am thinking about that like tje next candidate for motorizing ḿountain bike. Is it more quiet? Are there any strange issues with that motor? How many Volts do you use to feed the Cyclone?

Click to expand...

The motor is lightweight and powerfull but very noising and the stock bracket, freewheel, chainrig is poor quality. I had to buy 153mm bottom bracket on UK eclipsebike. I have older controler and dimensions are strange. I can't efiiciently pedal asist. I use 12S 10Ah lipo and motor can climbing almost everything. Range is circa about 20km in mountain terrain.
You can see some video on my playlist:
https://youtu.be/DL-8XJ7sQpM
https://youtu.be/O9piWnzIH_E

Nice videos, especially the autumn one. Your bike remains me more like "motorbike," mine is more in bosch pedelec vien, because I have to pedal all the time (that can be sometimes problem, but it encourages me to pedal so consumption is quite low). I also bought 153 mm botom bracket on UK eclipse, because it is imposible to buy it in my country. You said that You can't effeciently pedal asist, is it because of some health rescriction or the motor is not well geared down and cadence is too high...?

dingos said:

Nice videos, especially the autumn one.

Click to expand...

In fact, speed was greater than on video, beacuse I tested some setup on my camera. And also camera flatening slope.

dingos said:

Your bike remains me more like "motorbike," mine is more in bosch pedelec vien, because I have to pedal all the time (that can be sometimes problem, but it encourages me to pedal so consumption is quite low).

Click to expand...

And that's why I like your project. I love mtb, pedaling and I'm looking for something, what can help me climbing easier and faster or will allow at all climbing, beacuse I don't like push bike uphill.
I bought Cyclone middrive kit to lift my children uphill on haul. And he liked it so much, that he didn't want to pedaling anymore. So I push away e-bike

You said that all the time pedal asist, can make sometimes problem. But I understand that you have throttle and when something goes bad, you always can off engine speed? Danger may be a problem with cut throttle.

dingos said:

You said that You can't effeciently pedal asist, is it because of some health rescriction or the motor is not well geared down and cadence is too high...?

Click to expand...

Cadence is too high.You can read this thread and other: https://endless-sphere.com/forums/viewtopic.php?f=28&t=73027&hilit=cyclone+1680+overheating

Overall the system seems safe. I have thumb trottle on the left side on handlebar. If something happen you loose the throttle anyway. Another "safe system" is connection between battery in backpack and wire from the bike, there is connector XT90 and when I fall or forgot that I was connected to bike, I always uncosciously disconnected the connector very easily. I think in very technical terrain is better dual freewheel system (Cyclone) because it behaves more like motorbike. For example, when I stop in very steep slope I can have problems to get back into the saddle and contiune forward, but it is the same with normal bike or Bosch pedelec system. With Cyclone I can use just throttle and leave my legs on the ground to balance the bike, but it is impossible with my system, with Bosch or normal bike....