Motor has no torque problem please help!

Hi , guys just bought a new motor it's a cyclone gear less big motor for my mid drive ebike, I have previous to this been using a cyclone geared smaller motor with no problems , I connected the motor up using the same wiring combination as the small motor , the motor spins up fast and smooth in the correct direction , so I thought all is good!

Took it for its maiden ride and it has no torque at all and my amp meter Shows its not pulling any amps ?!?

Any ideas what I've done wrong?

I've used the same throttle and 35amp 48v controller I used for the old motor , just literally swapped motors and kept the same wiring using turnigy lipo 8 ah 2 p 2s

I'd really appreciate any help/ advice thanks in advance!!
Nick

I have just temporarily sellotaped the battery etc to the bike as you can see,

I found one connector to be slightly corroded

Here's some pics

Have you adjusted the gearing to compensate for not having the gear reduction in the motor? That could drastically change the feel of the bike and be very destructive to your controller if you haven't.

Clay

Found out why the watt meter was reading 0.00 amps it was connected the wrong way round ! Doh!

But the bike doesn't seem to be running at all well seems very weak and pulling quite a lot of amps and this is in the easiest gear on the bike ?? So I'm a bit confused do you think the hall wires are wrong? Or does the motor need some kind of gear reduction? Anyone else running one of these motors?

The motor is 7 tooth which drives a 44t, which in turn is driving the rear via a tiny 24t on the crank to a 34 t cog on the cassette ( thanks for reply clay btw)

please post a link to your motor & its specifications.
from a quick glance you look over geared by an order of magnatude.......

looking at the 48v motor 1/2way down the page:
http://www.cyclone-tw.com/dc24.htm

if that motor has a kv rating of 85ish (4000 rpms on 48v)
you are trying to spin your cranks (roughly) at 637 rpms

Using your gear ratio's above, in your slowest gear you trying to start out at 35mph......to fast for that motor & controller set up.

Here's a pic of the motor

48v to 72 v 3600 rpm to 5400 rpm

So how do I get the motor running ? I've seen other people on YouTube using this motor and it doesn't look like their using any kind of gear reduction at all so I'm confused , thanks for the replys

Are you shifting gears as you ride and accelerate? I can't really tell from the pictures if you have any gears to change to. As it sounds like it was suggested, you probably need to change gears. I'd be pretty shocked if someone decided to go with a mid drive setup but neglected to have a range of gears. That honestly would sound like a guy buying a bicycle frame and being confused when it doesn't work without wheels.


'quite a lot of amps' doesn't mean a whole lot to me. Are you sure the CA has the correct rshunt value?

You definitely need to adjust the gearing. You either need to build a gear reduction from the motor to the crank. Or change the crank sprockets. Or change the final drive sprockets. It will all depend on if you want to pedal along with the motor, or want the motor to even drive through the crank. There are quite a few gear calculators online to help you figure out the size sprockets you need at which stage to achieve the speed you want. You need to know the rpm of the motor fist though. If the calculator says something crazy, like 100mph, then you are way over geared and you will never get there.

Your old motor has a gear reduction on it and that needs to be replace in another way with your new motor that does not have that. Have a good look around through the non-hub section for others builds and you will see what others have done to achieve this. There are many good examples of different ways to do it.

Clay

Thanks clay will look into it,

To bowlofsalad: Yes the bike has 8 gears in the easiest gear it still has no power just judders - what I mean is I've seen other bikes using this motor with the bikes normal rear cassette with no other gear reduction and they don't appear to be having any issues like I'm having so was worried I maybe wired the halls signal wires incorrectly

Remove the chain and check no load Amps and/or smooth motor operation?

The bikes pulling about 20 amps to get started with the rear wheel off the ground then tapers back down to about 8 to 10 amps I'm feeling like that's a little excessive ?? That's with a 34t on the cassette they don't come a lot bigger than that and the crank sprocket is 24t and they don't come much smaller than that so changing the bikes sprockets to reduce the rpm is going to be nearly impossible if you see what I mean. And yes the shunt value I'm sure is correct on the watt meter

With no chain the motor spins fast and smooth but under load has no power

nickjs hi
Your motor is 2400W 48V, is that right?
This is a brushless motor with power after some km/h and not a geared motor with a lot of power when it starts.
You can connect the 100A Kelly controller to your pc to see the settings. You can take the software from here:
http://www.turbobikekit.com/3ps-cyclone-chainwheel-fast-electric-high-quality-bike-kits-kit/convert-to-electric-fast-bike-kit-cyclone-3-chainwheel-Kit-2400-Watt-48V
Check please if you like if your 100A Kelly has the settings:
1) Torque and not speed
2) Throttle effective staritn position: Up to 30%
3) The Boost function is on
and answer to me after this. :wink:

nickjs said:

The bikes pulling about 20 amps to get started with the rear wheel off the ground then tapers back down to about 8 to 10 amps I'm feeling like that's a little excessive ?? ...

Click to expand...

I've no experience with that motor, but yes it does sound excessive!

It will be good if you give a little more power-torque when it starts (you can do it from the Kelly controller's software)
When the motor starts does not give all the power because the bike will overturn

400-500W to turn that motor no load sounds like you may have a false positive wiring combo. Pick either the halls or phase, whichever is easier to swap, and try the other 5 combos using small pulses of the throttle. If you get one that spins smooth, it will probably be a reverse, but try it WOT no-load and measure the current.

If your gearing seems right compared to others, then no torque is another indicator of wrong wiring, so 2 strikes makes it pretty likely.

Once it spins smoothly at low current in reverse, then swap 2, only 2, any 2 of the wires (halls or phase) that you were keeping static and go back to the others and find the right combo that will now turn it in forward direction.

Be careful about shorts while trying combos, and use small pulses of throttle. Once you get it right, wire and seal it up good. Use shrink or colored tape to make it color on color, and have fun riding with a whole new world of torque.

If anyone mentions trying 36 combinations and using spreadsheets, just ignore them because they don't understand 3 phase motor wiring and the simple math/logic problem involved, because there are 3 valid forward combinations and 3 valid reverse. Trying only 6 combos will tell you what you need to know. Just never try swapping both halls and phases. That's were people get screwed up. To be systematic choose one as your anchor point...eg controller yellow. Then try both possible of yellow on controller yellow. Then both possible of green on controller yellow. Then both possible of blue on controller yellow. You already tried one, so if you don't get a good result (probably spins backward) of the 5 remaining, then something else is wrong.

I usually get cocky with a false position right direction like you have, and swap 2 of the wires I'm gonna keep static right up front. Then I get my good forward high torque low current combo in at most 6 tries (actually 5 because I know the false positive isn't the correct one). I'm still waiting for someone to take me up on the money challenge for me to do it blindfolded. It's that easy.

John