Cute 100 Q100C CST Cassette Hub Motor for Lightweight Builds

[zukster]

Look what just hit the shelves. My bike is about to get one freewheel lighter

http://www.bmsbattery.com/rear-driving/618-250w350w-q-85100sx-motor-e-bike-kit.html

I'm sick of re-building Dura-Ace MF-7400 7 speed freewheels with newer SIS HG cogs. Now I'll be able to run a 9 or 10 speed XTR cassette on my lightweight MTB commuter and save weight with the best shifting possible!

 

[full-throttle]

Doesn't look like it's got much grunt

 

[zukster]

Is the right one a Q100C? What's the one on the left?

The specs show that the Q100C is pretty much the same as the Q100 rear. Both with 135mm drop-outs for a standard MTB bike. I find the Cute 100 almost as powerful as the Bafang SWXH (given the same input). Its lighter at 2.1kg, so the Q100 is my preferred motor for a lightweight build. The two Bafangs I converted to metal gears can handle more over-volting now - up to 16S - if you keep an eye on them for overheating. I only trust the Cute 100 up to 13/14S.

I'll probably try one of them right away. Its only available in 201RPM right now. A 328RPM version will be available in two weeks. Lina from BMSbattery just got back to me with this new info. She also mentioned she may have a cap that will convert an old Q100 to take a cassette. I am double-checking this. She said that the Q100 and Q100C are not quite the same, so it may be more than just a cap difference between them. I can't wait to open a a new one and old one up to compare !

 

[Kepler]

Have you run Q100 on 18S? Does the over volting really matter if you keep the amps under control with a CA? I wouldn't mind trying one of these also.

The 201rpm would be what I want anyway for 75V. My SWXH is doing fine with 500 to 600W most of the time and plenty of 800W peaks. If the Q100 could handle 500W, it would be a great option for me. I can keep the bike between 40kph and 50kph on flat ground with 500W (with me contributing of course )

 

[zukster]

Have you run Q100 on 18S? Does the over volting really matter if you keep the amps under control with a CA?

I tested the Q100 at 15S with the BMSbattery.com KU63 controller, but just around the block. Nothing blew up or melted, but I suspect the KU63 has a 63V capacitor in it so 15S*4.2V = 63V is pushing your luck. So I am more comfortable at 14S for my bike with the KU63. The controller says 15 amp max.

I ran my Bafang at 18S (75V) a few times with ebike.ca's 20 amp controller. The nylon gears stripped though, so I switched them to metal. I find its prone to overheating on hills or under load for 14S and up if you don't keep an eye on it - it can get too hot. I burnt out an early SWXH this way so I know. It seems pretty tough with the metal gears as long as you don't overheat it.

Maybe you could use the CA to monitor amps and help with this somehow? With the Bafang anyway. I really don't know how much abuse the Q100 can take. I have not used it for pulling a trailer. I thought it was too small. It does have two sets of planetary gears stacked to achieve its small size however, so this would spread out the load over more gears, so perhaps they would hold up okay under more of a load.

If I was going to try this I might try 16S limited to 15A to start with, and see how it holds up. I'd try it one of Lyen's programmable controllers but I'm currently working with him to get the controller working better with the Cute 100. Once that is sorted out, I can program the controller to a max of 15A and give it a try. If I get that far before you, I'll let you know.

I just ordered a new crank that has 48/36/26. I'll be looking forward to trying the 328RPM Q100C and a cassette with an 11T cog. The bike will then be able to be peddled at the higher road speed the 328RPM wind will take the bike up too. I like to be able to peddle the same speed the motor can take the bike up to on the flats.

 

[full-throttle]

Is the right one a Q100C? What's the one on the left?

viewtopic.php?f=49685

Judging by the stator size it won't be very strong..
I had a wide Q100 (could only fit a singlespeed sprocket in 135mm dropout) and it was weak

 

[chvidgov.bc.ca]

I'm running several Cute 10s0 on 9 FET KU93 controllesr at 16S LiFPO4 with each with one of their shunts cut, after I burned out several KU63s. I measured peak amps on that deliberately crippled KU93 combo at 11.7 amps, which is around 650 watts peak power spikes. No issues so far. ECrazyman makes a 48v 15amp controller that runs the Cute 100 nicely also - I've got one - that is more like peak wattage in the high 700 watt range. Good idea to pedal when you can and gear down to help out. I think it will hold up. The KU63s were also 15 amp controllers but weren't able to run 48v for more than a couple of months without damage - the same amount of power as the nominal 48V controllers I'm using now. I don't think I would go beyond 15 amps at that voltage.

 

[zukster]

I had a wide Q100 (could only fit a singlespeed sprocket in 135mm dropout) and it was weak

That does not sound like a Q100. All my Q100s have 7, 8, and 9 speed freewheels on them and fit 135mm dropouts with little or no spreading. Sounds like you had a Q128, which is wider that the Q100.

 

[zukster]

The KU63s were also 15 amp controllers but weren't able to run 48v for more than a couple of months without damage - the same amount of power as the nominal 48V controllers I'm using now. I don't think I would go beyond 15 amps at that voltage.

I ran one at 14S 55v for about 6 months riding to work 30km 2-3 time a week. The other one my son rode to school for a year at 13S 48V. I still have both motors and KU63s and they are fine. I wonder what might be different about your experience. Maybe weight of rider and bike are more so more of a load on the motor/controller. I'm 150lbs and bike was about 35lbs with battery. My son is 135 and his bike was about 35lbs too. Didn't use either for towing either. What was your setup? What kind of batteries?

 

[patpatbut]

Do you know if they are supplying Q100C 250w version as well?

Pat

 

[zukster]

You can run most hub motors higher or lower than the specs. When over-volting (Power Watts = Volts x I (current) ) the Cutes and Bafangs are going higher than the average 350W they spec. I run my bike and Cute 100 at 14S with a Cute 100 and KU63 controller. I run my daughter's Cute 100 and KU63 at 8S.

For Lipo, the Voltage window for my bike would be 3.2v*14S(low batter cell cutoff - 4.2*14S(fresh off the charger) = 45-60 volts.
For my daughter it is 3.2v*8S(low batter cell cutoff - 4.2*8S(fresh off the charger) = 25.6 - 33.6 volts.

Both setups using the KU63 and Cute 100 work fine. Its very flexible.

As a note re my daughters bike and 8S, the KU63 LVC low voltage cut off is 27.5, so the controller will actually cut of the power when the 8S cell average drops below 3.4 volts/cell. Its nice to have BMS built into your battery that cuts off at 3.0-3.2 (they are all different). The KU63 adds protection beyond this because its cut off is even better for the health of the batteries by cutting them off at 3.4v instead. There is very little energy left in the battery once the cells are below 3.6v, so this works fine.

 

[chvidgov.bc.ca]

I am using 16S Pings and Headways with the Cute100s, mostly running around 52-53 volts.

 

[-dg]

It does have two sets of planetary gears stacked to achieve its small size however, so this would spread out the load over more gears, so perhaps they would hold up okay under more of a load.

No. It has two sets of gears to get compound reduction, not to spread the load. The single reduction set is going to be stronger since the gears are wider.

 

[full-throttle]

I had a wide Q100 (could only fit a singlespeed sprocket in 135mm dropout) and it was weak

That does not sound like a Q100. All my Q100s have 7, 8, and 9 speed freewheels on them and fit 135mm dropouts with little or no spreading. Sounds like you had a Q128, which is wider that the Q100.

Well.. it was. 150mm axle Q100 converted to 135mm.

 

[zukster]

I am using 16S Pings and Headways with the Cute100s, mostly running around 52-53 volts.

That sounds safe enough to me. I guess I should use pack voltage instead of 14S. My LiPo 14S pack max voltage is 4.2v max charge per cell * 14S = 60V and your 16S LiFePo4 16S pack voltage is more like 3.6v max charge volts per cell * 16S = 57.6v.

 

[zukster]

It does have two sets of planetary gears stacked to achieve its small size however, so this would spread out the load over more gears, so perhaps they would hold up okay under more of a load.

No. It has two sets of gears to get compound reduction, not to spread the load. The single reduction set is going to be stronger since the gears are wider.

I don't agree but I will ask a couple of mechanical engineers I know to double-check. Or I could do a trailer torture test

 

[d8veh]

The gears are two-stage. The larger diameter is helical and is driven by the motor spindle gear. The smaller diameter is straight cut and drives the hub ring-gear. The 24v version has single stage gears.

 

[esp]

Thinking of buying one of these for mountain bike. Are you at present using this motor and if so how do you like it. thanks Espen

 

[zukster]

I think they work great. I'm using everything from an 8S to 14S Lipo packs on them. The 8S with a 3 speed switch on my daughters bike. She can really climb hills with the hub in a 20" wheel!

I just added a Q100C to my show bike with an XTR Cassette. The bike weighs 29lbs without the battery pack. That's good enough for me now. Shifts like a dream to with XTR shifters and derailleurs. All 9 speed. The freewheeling mechanism is in the hub portion that sticks out shown in the last picture, just like a freehub. The freewheeling is not as smooth as my modified Dura Ace MF-7400, but at least I have 9 speeds and better shifting now, I could only get 7 cogs out of the MF-7400.

 

[d8veh]

They're nice little motors for light-weight builds or 2WD. I've got several of them. The original Q100 and the Q100C (CST) are available in 201 rpm and 328 rpm. They now have the Q100H with 260 pm.

 

[athletic91]

Hi i was wondering what cassette tool you guys used ? I had to drill out the centre of my tool for it the clear the hub motor axle

 

[zukster]

For a Shimano, DNP, and a few other thread on freewheels,

http://www.ebikes.ca/store/photos/FWTool.jpg

For the newer Q100C hub, a Shimano lock ring tool,

http://www.parktool.com/category/freewheel-cassette

 

[d8veh]

That freewheel removal tool is for free-wheels. The Q100CST has a cassette, which has a different internal spline, so we now have the same problem to find a tool with a large hole in the end. I found mine in a local bike shop. I chucked the packaging, so I don't know who made it.

 

[esp]

Thanks for your input! I was going to order the KU65 controller along with it. Is there any advantage or disadvantage in putting a bigger controller on it. Have a 36v 10ah Lifepo4 but might what to over voltage a little. Bought that battery a year ago from BMS with a SWXK5 front hub. The battery seems to be considerably weaker now and was expecting a little longer life out of it. E

 

[zukster]

The Park FR-5 cassette tool fits over the axle. It was 10 bucks at my LBS.

The KU63 produces plenty of power on a 13S pack and the Q100. That's 55v off the charger or about 48v nominal/average. I use more voltage than that or a more powerful KU65 or you'll likely burn out the motor unless you're extreme careful.