Chinese Grom Clone with 8K QS Hub and Nissan Leaf G2 battery pack build

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roadpupp   1 mW

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Chinese Grom Clone with 8K QS Hub and Nissan Leaf G2 battery pack build

Post by roadpupp » Sep 09 2020 9:24am

https://advrider.com/f/forums/electric-motorcycles.102/

Hey all-

Been lurking here since May when I ordered my E Grom from Belmonte Bikes. Since it arrived, I have done a few upgrades but have a ways to go. I will share my progress here and solicit any suggestions. Thanks in advance, this is a forum full of interesting projects!

So I started with a lead acid 72 volt system with a 2,000 watt QS hub motor.

Upgraded so far:
Honda Grom Forks
Aftermarket Shock
Brembo Single pot front caliper
SS brake lines
Machined Brake levers
Fender delete and integrated blinkers in rear brake light.
8,000 watt QS Hub
13” rear , 12” front - Pirelli Diablo Rosso tires
11 Nissan Leaf batteries (not installed yet)
80 amp Greentime controller (not installed yet)

Future upgrades: a better controller.

So I have been riding this thing stock for a few months and it is fun around the neighborhood but lacks the grunt I am looking for. Between this forum and ADV riders, there are a few people who have upgraded these bikes. The Honda Forks made a great bit of improvement and the Brembo single pot is better than the two pot chinesium front caliper that came on it. The tires also feel better but I am not pushing them on the stock power.

The forks bolted right up. The rear shock made for Groms also bolted up easily once I had the rear wheel off. Stainless lines took a bit of measuring but eventually I got them working well.

Hub motor.
This was about $550 Plus $250 shipping! from QS. It is made to work with 200mm drop outs so it is a direct replacement for the stock hub/wheel. One thing to note is the motor came with no spacers. I took the old spacers and had one machined (cut into three pieces) and I was able to mix and match the spacers to work on the new hub. I do have some concern that the slotted hub puts a ton of force on the keeper plates on the swing arm to keep from spinning under load. Perhaps socking down the nuts and spacers will provide more structure.

The rear hub with mounted 13” tire is quite a bit bigger than the stock one. The fender may need some fabrication.

Battery pack
I bought 11 cells from Tech Direct. They are used and I bought an extra incase I had a bad one. Probably should have bought pouch batteries on such a small bike. This weekend I am going to drop the battery box and see about expanding it an inch in width and 2.5 inches in depth. This will allow me to get 6 in the bottom box and 2 on either side standing on top of the others.

I will post pics when I am done.

Any feedback is appreciated. Still haven’t figured out a BMS for 20 cells (2 per leaf cell) but will try to get it running before I start working the batteries. Any suggestions for a BMS with 10 or 20 sensors is appreciated.

Charging to 85 volts through a $150 Lithium 72 volt charger.

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johnnyddn   1 mW

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Re: Chinese Grom Clone with 8K QS Hub and Nissan Leaf G2 battery pack build

Post by johnnyddn » Sep 13 2020 1:46am

I've been trying to find low mileage salvage Leaf batteries but I haven't had any luck. Let me know how the batteries from tech direct hold up for you.

roadpupp   1 mW

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Re: Chinese Grom Clone with 8K QS Hub and Nissan Leaf G2 battery pack build

Post by roadpupp » Sep 16 2020 8:25am

Will do. They are 7.6 volts and from Tech Direct. Fresh batteries are very hard to find.

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Dui, ni shuo de dui   10 kW

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Re: Chinese Grom Clone with 8K QS Hub and Nissan Leaf G2 battery pack build

Post by Dui, ni shuo de dui » Sep 16 2020 7:51pm

roadpupp wrote:
Sep 09 2020 9:24am
8,000 watt QS Hub

80 amp Greentime controller (not installed yet)

Whuuuuutt???
Man, you have a 8000W QS motor, why would you install such a puny controller?
You can go crazy with this motor, it can take up to 1000A per phase!
(though I wouldn't recommend you such insane power on a small bike like this, stay on the safe side, 600A/phase and 2-300A battery would already be ridiculously fast)
roadpupp wrote:
Sep 09 2020 9:24am
I do have some concern that the slotted hub puts a ton of force on the keeper plates on the swing arm to keep from spinning under load
Yes, your concern is justified, those motors have a ton of torque and sometimes the plates can be destroyed (which is a problem since then the motor stator spins and ruins the phase wires).
On my bike the plates hold just fine, but on a friend's bike we had to machine a clamp out of 7075 aluminumin order to clamp firmly the axle to some point further on the swigarm. What puts the most stress on this is instant torque variations, if you like to start like a maniac from standstill then you might run into this issue. Your bike is lightweight though, so maybe you'll be fine without one, I suggest you to check regularly and to tighten the axle nuts hard.
roadpupp wrote:
Sep 09 2020 9:24am
Any feedback is appreciated. Still haven’t figured out a BMS for 20 cells (2 per leaf cell) but will try to get it running before I start working the batteries. Any suggestions for a BMS with 10 or 20 sensors is appreciated.
Go for the ANT BMS in 300A version. It will be good for lots of power (we tested it up to 600A battery, works fine), it's easy to hook up, easy to work with, reliable, it comes with bluetooth and a screen that displays all kind of info, it's cheap.... I have nothing but praises for this thing, really great product.
I'm impatient to see your battery build!
:bolt: New Build in Progress: Electric Roadster, 30 000W Kelly KLS72701, 24S2P A123 cells :bolt:
viewtopic.php?f=12&t=109246

:bolt: My electric Ninja 250 clone: 16 000W Sabvoton 72200, 23S2P A123 cells : :bolt:
viewtopic.php?f=12&t=90032

:bolt: My electric Scooter: 11 000W Sabvoton 72150, 72V 50Ah LiFePO4 cells: :bolt:
viewtopic.php?f=12&t=75912

roadpupp   1 mW

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Re: Chinese Grom Clone with 8K QS Hub and Nissan Leaf G2 battery pack build

Post by roadpupp » Sep 17 2020 11:38am

Thanks Dui!

I read all your posts. Really cool stuff you are fabricating to make your bikes great!

I should receive a Kelly KS-S mini controller 72v good for 300A for 20 sec and 120A continuous. I am just getting this project together and bought a few controllers as I was conceiving the bike.

I suspect I won't be happy until it will do wheelies! Thank you for the tip on the hub studs, I think we will need to add something more structural to keep the motor from spinning. I have some ideas.

Will definitely look into the BMS you recommend, .

Thanks for your comments!
Roadpupp

roadpupp   1 mW

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Re: Chinese Grom Clone with 8K QS Hub and Nissan Leaf G2 battery pack build

Post by roadpupp » Sep 17 2020 11:46am

So I dropped the battery box, cut the bottom out and added 2-5/8" to the bottom edge and rewelded the bottom. The steel was so thin, we couldn't get a good bead so I settled for buttons every few inches. I will mount this and the wheels and make sure the bodywork fits and the ground clearance is at least workable.

Then probably JB weld outside/Silicone inside and Paint. Very little of it is visible but the button welds look like crap.

I was pleasantly surprised that 7 cells fit across the bottom. All 11 will fit nicely as long as the ground clearance is ok.
Needed thin plate steel and so this is how we cut it!

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j bjork   100 kW

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Re: Chinese Grom Clone with 8K QS Hub and Nissan Leaf G2 battery pack build

Post by j bjork » Sep 18 2020 5:43am

roadpupp wrote:
Sep 17 2020 11:38am
Thanks Dui!

I read all your posts. Really cool stuff you are fabricating to make your bikes great!

I should receive a Kelly KS-S mini controller 72v good for 300A for 20 sec and 120A continuous. I am just getting this project together and bought a few controllers as I was conceiving the bike.

I suspect I won't be happy until it will do wheelies! Thank you for the tip on the hub studs, I think we will need to add something more structural to keep the motor from spinning. I have some ideas.

Will definitely look into the BMS you recommend, .

Thanks for your comments!
Roadpupp
Still no use for this kind of motor with a controller like that.. You should probably been better off keeping the motor you had and just get a better controller. Are you sure those 300A is battery amps? In that case it could work, but be far from the motors potential. I am afraid it is phase amps..
This motor needs something like an asi bac 8000.
Maybe votol em 300 or something like that.

You are putting a garden hose on a fire truck.

roadpupp   1 mW

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Re: Chinese Grom Clone with 8K QS Hub and Nissan Leaf G2 battery pack build

Post by roadpupp » Sep 18 2020 8:14am

I had a sense that the controller is the weak point but I have just installed the motor and haven't built the pack yet.

I requested a quote on the BAC8000 looks to be a good size.

Thanks.

Roadpupp

j bjork   100 kW

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Re: Chinese Grom Clone with 8K QS Hub and Nissan Leaf G2 battery pack build

Post by j bjork » Sep 18 2020 11:49am

No harm in trying it with the controller you have, but it would be a shame if you thought "is this it, not very impressive"
When you are no where near using the potential of the motor. But I think you need to do something about the dropouts, or maybe the whole swing arm. It is good to make like clamps, so the shaft is held tight in the swing. And just use the nuts to hold it in position.

Did you see the seller here on the forum? People seems happy with him. It seems to be a good idea to avoid ERT, just have a look in the vendor relations corner, or what it is called.

John in CR   100 GW

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Re: Chinese Grom Clone with 8K QS Hub and Nissan Leaf G2 battery pack build

Post by John in CR » Sep 19 2020 3:10pm

Nissan Leaf cells need a bit of compression to get the most out of them and prevent them from swelling. Do you have all of the Nissan hardware that help you achieve even compression using bolts through the holes at the 4 corners without deforming the cans? Look up a pack teardown video to get an idea of what you need.

roadpupp   1 mW

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Re: Chinese Grom Clone with 8K QS Hub and Nissan Leaf G2 battery pack build

Post by roadpupp » Sep 21 2020 2:48pm

John-
That is a good point and one I didn't know about. Thanks! I was thinking of using threaded rod in the four corner holes. Now I definitely will. 4 of the cells will be used in two sets, so I will probably bolt those together but they won't have much compression. These are standing up on either side of the frame. The ones in the bottom of the Battery tray are squeezed to make 7 fit. I can run with 6 there and make room for endplates, or stuff 7 in and a small bit of foam and should have good compression.

Much appreciated! Keep the suggestions coming all. Finally have a Kelly KLS S and the battery box mod and the motor mounted, it is almost time for a test ride!

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Dui, ni shuo de dui   10 kW

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Re: Chinese Grom Clone with 8K QS Hub and Nissan Leaf G2 battery pack build

Post by Dui, ni shuo de dui » Sep 22 2020 2:03am

roadpupp wrote:
Sep 17 2020 11:38am
I should receive a Kelly KS-S mini controller 72v good for 300A for 20 sec and 120A continuous. I am just getting this project together and bought a few controllers as I was conceiving the bike.
Ah ok that's a bit better, but as bjork said, it is still far from your motor's potential.
Usually Kelly controller power ratings are phase Amps ratings, so I guess it should be around 120-150A battery. It isn't bad but it isn't amazing either.
If it's not too late and if your battery allows it, I suggest you to go for higher power.

Also, I'm not familiar with the leaf cells, how much amps can your battery setup reasonably deliver?
:bolt: New Build in Progress: Electric Roadster, 30 000W Kelly KLS72701, 24S2P A123 cells :bolt:
viewtopic.php?f=12&t=109246

:bolt: My electric Ninja 250 clone: 16 000W Sabvoton 72200, 23S2P A123 cells : :bolt:
viewtopic.php?f=12&t=90032

:bolt: My electric Scooter: 11 000W Sabvoton 72150, 72V 50Ah LiFePO4 cells: :bolt:
viewtopic.php?f=12&t=75912

roadpupp   1 mW

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Re: Chinese Grom Clone with 8K QS Hub and Nissan Leaf G2 battery pack build

Post by roadpupp » Sep 22 2020 8:18am

Dui-

Thanks
I just placed an order from the EU vendor here for an ASI BAC 8000 so I should have plenty of power soon.

Nissan Leaf G2 cells are listed as 66 amp hours and Maximum Continuous Discharge Current is listed as 130A. I have 10 or 11 cells that will be in Series. Website info seems to say they are a safe 10C discharge.

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Dui, ni shuo de dui   10 kW

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Re: Chinese Grom Clone with 8K QS Hub and Nissan Leaf G2 battery pack build

Post by Dui, ni shuo de dui » Sep 22 2020 8:38pm

roadpupp wrote:
Sep 22 2020 8:18am
Nissan Leaf G2 cells are listed as 66 amp hours and Maximum Continuous Discharge Current is listed as 130A. I have 10 or 11 cells that will be in Series. Website info seems to say they are a safe 10C discharge.
I'm not sure what to think since two informations contradict each other.
Maximum discharge = 130A
C rating 10C = 66Ah x 10C = 660A.

I get that the first rating is continuous and the second one is likely to be peak but that's quite a big difference. At first glance it seems a bit weak to me.
Please try to find someone on the forums who knows the Leaf's battery better than I do, just to confirm that it'll be ok with the power you intend to draw from it. Would be a shame to beat the battery to death.
:bolt: New Build in Progress: Electric Roadster, 30 000W Kelly KLS72701, 24S2P A123 cells :bolt:
viewtopic.php?f=12&t=109246

:bolt: My electric Ninja 250 clone: 16 000W Sabvoton 72200, 23S2P A123 cells : :bolt:
viewtopic.php?f=12&t=90032

:bolt: My electric Scooter: 11 000W Sabvoton 72150, 72V 50Ah LiFePO4 cells: :bolt:
viewtopic.php?f=12&t=75912

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JimVonBaden   100 W

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Re: Chinese Grom Clone with 8K QS Hub and Nissan Leaf G2 battery pack build

Post by JimVonBaden » Jan 05 2021 3:51pm

Welcome fellow ADV Rider inmate. Do you have a build thread on ADV?

Jim 8)

roadpupp   1 mW

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Re: Chinese Grom Clone with 8K QS Hub and Nissan Leaf G2 battery pack build

Post by roadpupp » Feb 02 2021 2:32pm

Jim-
Not yet. The project got stalled for a few reasons. I am back on it and will write it up when there are completed photos. Will post over at ADV rider then.

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JimVonBaden   100 W

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Re: Chinese Grom Clone with 8K QS Hub and Nissan Leaf G2 battery pack build

Post by JimVonBaden » Feb 02 2021 11:09pm

roadpupp wrote:
Feb 02 2021 2:32pm
Jim-
Not yet. The project got stalled for a few reasons. I am back on it and will write it up when there are completed photos. Will post over at ADV rider then.
Great, looking forward to it!

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