Cute Q100CST Smaller 42mm Flange Ver Open wt Vice Disc Rotor

I opened up my Cute 100 Q100CST to figure out the number of pole pairs so I could use it with the hall sensors properly with the ebikes.ca Phaserunner controller.

This is the newer Black 42mm flange to flange version of this motor. There was a previous version of this out before this that was a bit bigger, heavier, and had 47mm flange spacing. My old ones were all Silver. My new ones are all Black.

I built a tool to do this and I thought I would share it on the forum. In order for this to work, you need to clamp just the cap/lid part of cassette drive side of the hub in a vice. There is not enough of a lip to get a chain clamp onto.

If the hub is still in the wheel you do not need to build the disc board tool. You can put the lid of the cap of the hub face down and clamp the lid into the vice, and turn the wheel instead of the board, as shown below. The lid comes undone counter-clockwise, so you turn the board as shown counter-clockwise too.

Q100C CST 36V350W Rear Driving V-brake, rim-brake, Disc-Brake compatible EBike Hub Motor Specification:

1. Voltage: 36V.
2. For brake type: For V-brake, rim brake and disc brake.
3. Connector: Sensorless Waterproof, Hall sensor and sensorless compatible or waterproof hall sensor plug.
4. Dropouts: 135mm.
5. reduction ratio: 14.2
6. rotor alnico number: 16 (8 pole pairs)
7. Weight: 2.1Kg

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Wow!

Thanks for posting this - always good to have details on the new motors that come on the market. A few thoughts:
- It looks like removing the axle wasn't really necessary, right? Helpful to see how it goes together, though.
- You don't show the cassette side, but would it also be possible to remove the freehub body and use its mounting taps for leverage? I'm thinking that might be how it's assembled.
- How much trouble was it to get the halls back in the right place?
- You should contact Miles and/or spinningmagnets about adding this info to the Big List

looks like removing the axle wasn't really necessary, right?

Click to expand...

Strictly speaking no. But it makes it easier bending the wires and seeing how they go in. It puts less stress on them this way.

would it also be possible to remove the freehub body and use its mounting taps for leverage

Click to expand...

Yes, but it was easier this way by using a disc rotor and board. The disc goes onto the hub firmly. And the disc goes onto the board easily. You just need a hole saw.

To do it the other way there are problems. The cassette freehub does not come off the hub(it did in the older Q100CST). That would mean you would have to cut a whole just a hair smaller than the diameter of the sprocket in order to have enough material left to drill the 3 bolt holes in the board ; even so, they might not have enough material from the edge of the hole to not crack through. Also, hole saws only come in 1/4" sizes that big. So how do you get the hole the right size. So it worked easier the other way.

I just put it all back together the same way it came apart. If one was to disassemble it more than this, It might be best to score the sides of the inner hub and score the black axle to inner hub positioning, so you could put it back together exactly the same.

Now I wonder how to take out the freehub in case it needs replacing... prob further disassembly to get at the back of the plate behind the freehub... but I did not need to do this.

Good morning,

Do you know how to remove the freewheel now

I've just bought a new bike with this motor hub, so if one day I need servicing the bearings, it would be great to know how :wink: :wink:

Have you counted the teeth of the planetary wheels

Have a Nice Day.

Thierry

The hub freewheel is built into the cap that screws onto the main body. Its built-in and I don't think its serviceable. I have yet to wear out a freewheel on any hub, electric or non, so I would not worry about it. The freewheel mechanism has a bit of engagement lag compared to a higher end Shimano or Dt Swiss hub, but it works well enough, on or off-road. The motor is less than 100. If it ever needed major servicing I would order an whole new motor from bmsbattery.com for parts. If you did want to just do the bearings at some point, you would need to open the motor up and try to figure out their specification. They are probably a standard size(es). I never needed to count the teeth.

Thanks for your quick answer.

Thierry

Thanks for showing us it's guts. I've looked at a lot of these types of motors, and this one appears to be constructed very nicely.

Contrast this to the YTW-06. The axle interface is much less solid. The connection between the gear assembly and stator assembly is also much longer, but not well supported.

View attachment 1



The cute is significantly heavier, considering that it is rated for just a bit more power. But it seems to have a wealth of copper, so the power might be understated a little. I'm sure the extra metal elsewhere adds durability.

Bear in mind there are two versions of the Q100CST out there too. The one bmsbattery was selling at first several years back was silver and weighed about 5 lbs. The newer ones I bought within the few years are black and they are about 4.5 lbs. They have slightly different hub freewheel mechanisms too. The black freewheel is built into the screw on cap. The silver one is under the cap and you can actually access it when you take the cap off. They both seemed to work okay. I'm not sure why they changed it, but I really like the low 4.5 lb weight of the new black one.

I have also upgraded the clutch in a couple of them which was necessary when over-volting them and using them with a Grin Phaserunner at higher phase amps. This was for the black one below:

https://endless-sphere.com/forums/viewtopic.php?f=2&t=88397

When used with bmsbattery KU63 controller, the motor works just fine as is. I'll see if I can find a link to the older silver model.

The YTW-06 is impressively light at about 3 lbs. How much have a beating have you subjected it to?

I use my Phaserunner Q100CST 72V LiPo combo for on-road and off-road cross-country mountain biking and as long as you don't get too carried away with over-powering it, it works fine. I had a bit of trouble at 800watts. Limiting it to 700watts has proved very reliable for my use and weight(150 lbs) for about a year now. It was tricky getting the PR parameters to work properly with the Q100CST, but I eventually got it dialed in.