GNG, 1000W 48V BB-drive, $400

[skyungjae]

Hi All, I'm new here, so I'll try to keep the blindingly obvious questions to a minimum until I've settled in.

I'm looking at converting my MTB to electric and the Bafang with Lightning Rods mods seems the wise choice.

Can I use my Shimano SLX cranks / BB or am I forced to use their cranks BB combo?

I didn't know LightningRods was making anything for those Bafang crank drives. I'm actually interested in that system myself, but I don't think the square taper spindle could take the abuse of my kind of riding + my weight.

Anyhow, you'll likely have to use some sort of freewheeling crank system with the GNG. It's been discussed at length the different options you can use, but it seems like the Cyclone ISIS BB and freewheeling crankset is the most "drop in" or "off the shelf" option. I'm sure you could get away with using a standard BB and crankset, but you'd need a longer spindle + the pedals would spin when throttling (this can be very dangerous). I considered this myself until I took the plunge with the Cyclone set.

 

[scorpionice]

skyungjae,

So are you saying the GNG and Lightning Rods kit is the way to go? Planning to purchase his scratch build that includes all his MOD until this Bafang showed up. But some reviews already broke their spindle in the short period of time. And until now every time you ask for the spindle's toughness, the US supplier does not answer this. Don't get me wrong, just saying. Peace.

Hi All, I'm new here, so I'll try to keep the blindingly obvious questions to a minimum until I've settled in.

I'm looking at converting my MTB to electric and the Bafang with Lightning Rods mods seems the wise choice.

Can I use my Shimano SLX cranks / BB or am I forced to use their cranks BB combo?

I didn't know LightningRods was making anything for those Bafang crank drives. I'm actually interested in that system myself, but I don't think the square taper spindle could take the abuse of my kind of riding + my weight.

Anyhow, you'll likely have to use some sort of freewheeling crank system with the GNG. It's been discussed at length the different options you can use, but it seems like the Cyclone ISIS BB and freewheeling crankset is the most "drop in" or "off the shelf" option. I'm sure you could get away with using a standard BB and crankset, but you'd need a longer spindle + the pedals would spin when throttling (this can be very dangerous). I considered this myself until I took the plunge with the Cyclone set.

 

[jateureka]

I'm looking at converting my MTB to electric and the Bafang with Lightning Rods mods seems the wise choice.

I don't think Lightning Rods is doing a mod for the Bafang.
This thread that you have posted in is all about the GNG, which uses an external drive to the BB, so BB/crank/freewheel parts are more readily interchangeable.
I believe the Bafang crank drive BB/crank/freewheel is more customised/incorporated into the unit and not readily available as replacement parts as yet.

 

[Joe T.]

Hi All, I'm new here, so I'll try to keep the blindingly obvious questions to a minimum until I've settled in.

I'm looking at converting my MTB to electric and the Bafang (oops; correction...GNG) with Lightning Rods mods seems the wise choice.

Can I use my Shimano SLX cranks / BB or am I forced to use their cranks BB combo?

Before I built my current bike I simply installed the GNG kit on my old bike. The Bottom bracket that comes with the kit is a little wider for clearance. I'm not clear on the concerns over the freewheel. The motor powers the sprocket and the freewheel is only stressed by the rider. It all worked good enough for the money I thought.

 

[LightningRods]

Hi Guys-

Nothing for the Bafang at this time. I have nothing against them. I just have my hands full of GNG at the moment.

Unfortunately if you have a really nice bike and want to run the GNG you have to remove your quality BB and install theirs. Or buy the Cyclone ISIS which seems to be the best bet. I have those in stock with either 1/2" chainwheels or 219 kart chain on the secondary drive.

I am still looking for a reliable source for these motors in China. Vendors are either flakey like Mister Tao or they expect you to buy at least a hundred units at a time. I really like these motors. It's what makes the GNG worth messing with. If I have to buy 100, I will.

For the time being buying a complete GNG kit and getting it upgraded is not that bad a way to go. The motor and jackshaft are fine and the controller/throttle will at least get you on the road cheap. I will work with people and buy and convert the GNG for them, delivering a ready to run Lightning Rods conversion. Think of it as a tuner GNG like a Saleen Mustang or a Callaway Corvette.

The vendor providing the freewheel adapter is, of course, running behind schedule. I was told it would ship last Wednesday, now it's shipping this coming Tuesday. I hope he's right. My shop is so full of e-bike parts that I can't turn around in it. All held up by one little part. The good news is that I will have 100 of them now and will reorder if I see them running low. I am stocked up and ready to go on everything else.

 

[skyungjae]

The vendor providing the freewheel adapter is, of course, running behind schedule.

This is the adapter to run the freewheel in the larger primary pulley?

How's progress on the freewheelless adapter for the big primary pulley for those who want to keep the 12T (or 13T in my case) on the secondary side?

 

[LightningRods]

The vendor providing the freewheel adapter is, of course, running behind schedule.

This is the adapter to run the freewheel in the larger primary pulley?

How's progress on the freewheelless adapter for the big primary pulley for those who want to keep the 12T (or 13T in my case) on the secondary side?

It's a Christmas miracle! The freewheel adapters have shipped! That means that we are less than a week away from the complete 25mm GT pulley and belt conversion. I'm casting the pulleys in black now and they look great.

For folks like my friend Skyungjae who want to keep the freewheel on the secondary side I have worked out a hub adapter. I honestly think that having the freewheel on the big primary pulley is going to be great, but it's not essential. I'll be casting the no freewheel adapters after I get the rest of this stuff sorted, probably after the first of the year.

I got my three big block motors from Mister Tao. One has cosmetic damage and another one is trashed. They put like one sheet of crappy styrofoam that turned to powder in the box with three 11 pound motors. The steel helical gear was just the tool for mangling the aluminum case fins. I am bummed. Right now Mister Tao is being quiet in response to my damaged goods complaint. I expect them to try to squirm and deny responsibility. We'll see what happens.

 

[exco]

I already had the motor apart ... but can't find my notes on the hall sensors ...
Are these at 60° or 120°?

 

[LightningRods]

-

 

[full-throttle]

Are these at 60° or 120°?

The hall sensors are spread over 60 degrees.

Electrical spacing is 120°

 

[kiwifiat]

I got my three big block motors from Mister Tao. One has cosmetic damage and another one is trashed. They put like one sheet of crappy styrofoam that turned to powder in the box with three 11 pound motors. The steel helical gear was just the tool for mangling the aluminum case fins. I am bummed. Right now Mister Tao is being quiet in response to my damaged goods complaint. I expect them to try to squirm and deny responsibility. We'll see what happens.

My experience exactly with MisterTao, shipped a bashed around second hand motor in a substandard box and no response whatsoever to numerous emails to the "official" customer complaints department backed by photos of said motor. I must say that dealing with MrTao is a stark contrast to my very good experience importing magnets for my motor build direct from a factory in China and a similarly positive experience importing an AC/DC TIG welder again direct from the factory not a unreliable reseller. The takeaway being that we should really try to locate the manufacturer of these big block motors and give Mistertao a big sidestep.

 

[LightningRods]

Mister Tao's idea of a solution is to keep telling you that they packed your motors "very well" when you saw with your own eyes that they had put one sheet of crappy Chinese styrofoam in between three motors as the sole protection. In my case they actually implied that postal inspectors had removed all of their packing material! This is the situation: You've hired a high school dropout to valet park your Rolls Royce. If they tear a fender off on a concrete pillar they are going to claim that your Rolls came in that way. DO NOT BUY ANYTHING FROM MISTER TAO!!!!

 

[exco]

^^ same experience ordering from gngelectric...

My GNG build finally took shape.

 

[bzhwindtalker]

I got my three big block motors from Mister Tao. One has cosmetic damage and another one is trashed. They put like one sheet of crappy styrofoam that turned to powder in the box with three 11 pound motors. The steel helical gear was just the tool for mangling the aluminum case fins. I am bummed. Right now Mister Tao is being quiet in response to my damaged goods complaint. I expect them to try to squirm and deny responsibility. We'll see what happens.

Why is it so hard to get hold of those motors? I had limited succes in my attempst to place an order of 10 "big blocks" to various sellers on alibaba...

 

[LightningRods]

Why is it so hard to get hold of those motors? I had limited succes in my attempst to place an order of 10 "big blocks" to various sellers on alibaba...

The only answer I have is that these motors are designed for use on three wheeled 'rickshaws' and are typically sold with a geared reduction and differential. It's unusual to find them without a cooling fan. I have found two manufacturers in Shanghai and was in negotiations with one of them when they stopped responding. I was trying to get 20 motors instead of their typical 100 minimum and I think they just decided I was too small time to bother with.

The 25 GT drive belts that I ordered from the US Midwest shipped today. I also just picked up 35 5 bolt freewheel (ACS, Cyclone HD and White Ind) to #219 kart sprocket adapters from my laser shop today. I'm building up Cyclone ISIS BBs with both 219 and 1/2" bicycle chain wheels.

 

[bee]

Jon at GNG finally came through and sold me some replacement GNG parts (motor cover, jackshaft spindle)

 

[skyungjae]

Jon at GNG finally came through and sold me some replacement GNG parts (motor cover, jackshaft spindle)

Whoa, how did you sweet talk him into doing that? Maybe I can sweet talk him into the 1.1 parts I need to do the wider belt conversion with the sealed jackshaft.

 

[bee]

Maybe he was sympathetic because both GNG kits I bought from him are currently broken

I also sent pictures of the parts I needed, and did ask like 3 times over the last few months!

 

[byebyepetrol]

Lightning Rods; thanks for the info re: likelihood of using my existing SLX cranks with the GNG kit.

I expect I'll go for the 36v GNG (250w commuter in Australia), Lightning Rods Mods inc. wider belt drive.

Any recommendations on the best plug n' play battery for this setup? I'm leaning towards LiFe and mounted using
drink bottle fittings.

I run Magura hydraulic disc brakes, If I install the GNG, can I still use them or am I forced to use V-brakes?

I'm excited about the prospect of laughing in the face of headwinds and hills.

 

[t0me]

Got some weirdness happening with my GNG, hoping someone can shed some light.

So, its been sitting for a little while waiting for some new chain - and waiting for some 25 chain sprockets and gear. In the mean time I already had some 04b coming and it arrived today so I fit that.
Fire it up. Nothing. Dead. Power to the controller, nothing coming out the other end. I hooked up another controller I had (for a 48v 1000w hub motor) and the motor ran so I proceeded to swap that onto my bike...
Got it on... It runs, but at pretty low RPM, gets to about 20% throttle and stays there... until there's some resistance to the wheel, and then it applies full throttle!!!
I'll recap that. I wind the throttle onto full, the motor runs as if I've only got about 20% throttle. I apply some resistance to the motor (I apply the back brake a little) and the motor roars to life giving full throttle (and looks like about 34A on this controller with no mods so that's nice) but if I let go of the brake, its back to 20% throttle.
I should confirm, there is no brake wires attached. Just the normal 3 wires to the throttle and 1 wire to power for the LED's. I tried another throttle, same thing.

So, what's going on there?!?!?

With the original controller, when I fired it up, the motor turned half a turn and then stopped, never moved again with that controller. Only change since it last ran perfectly (and broke the chain) is that I added a little more silver solder to the shunt. I checked the board, there's no solder splashed anywhere else, there are no swollen caps, no obvious scorch marks or broken components, just a controller that doesn't work. I haven't done any testing on it with a multimeter, not sure what I should even test.

So what's going on there too?!?!?!?

Next, what other controllers will work?are people using. I want to stick with 48v cos that's what I've got battery wise. I'd like to run up to 35A I guess. I don't think these battery packs are supposed to run much more (the BMS in one of my packs is supposedly set to 30A - ping lifepo4 15ah 48v - but has run fine at 33A on the original GNG controller).

Ive been without the ride for a couple of weeks now and I'm hanging out to get out on it!! I even resorted to taking a bike out and PEDALLING IT!!!! Save me!!!

 

[Whiplash]

I got my three big block motors from Mister Tao. One has cosmetic damage and another one is trashed. They put like one sheet of crappy styrofoam that turned to powder in the box with three 11 pound motors. The steel helical gear was just the tool for mangling the aluminum case fins. I am bummed. Right now Mister Tao is being quiet in response to my damaged goods complaint. I expect them to try to squirm and deny responsibility. We'll see what happens.

Why is it so hard to get hold of those motors? I hadlimited succes in my attempst to place an order of 10 "big blocks" to various sellers on alibaba...

Uh oh! That bikes going to fly now! Lol!

 

[Whiplash]

So the 11lb big block cab handle how much power at say 48v peak and continuous? That's a nice motor if its capable of say 3-4000 watts!

 

[t0me]

Followup on my previous post.

To clarify.
Under no load - bike back wheel off the ground - applying full throttle only supplies about 20% speed to the back wheel.
Apply the rear brake (resistance) without moving the throttle from the full power position - it will then apply full throttle to the rear wheel.
Throttle response is then normal until the throttle is released, then next time you try to apply throttle it will only go to 20% speed (until you apply some brake again).

I checked with my other battery this morning, its not that (was a suggestion via pm).

I'll be removing the solder from the shunt of the original controller today to see if I can resurrect that, and have looked into getting a Lyen controller (will likely get one regardless) but that will take 2-3 weeks to arrive and I really want to be able to go for a ride or two over the holidays...
Any and all advice, idea's, critisism's gratefully accepted.
Happy to move this to a separate thread if its taking the good work in this thread sideways at all. (might be good to have a thread to discuss controllers being used with these motors too).


Oh and the controller I'm currently trying to use is from a kit almost the same as this (only difference is the kit I have was the front wheel version) - http://www.ebay.com.au/itm/Electric-Bicycle-E-Bike-Conversion-Kit-Brushless-Motor48V-1000W-Rear-Wheel-Rack-/150956506830

 

[r3volved]

Did you have your wheel off recently?
Almost sounds like the breaks are messed or your wheel is mounted a bit crooked or something.
Reseat the wheel. Maybe take the pads out of your break and try it. Don't pull the breaks though with the pads out and no wheel mounted.

 

[t0me]

This is an issue with the motor or controller, nothing to do with the brakes.
The brakes are only relevant in that I'm using them to apply the resistance. They're not connected to the motor or controller in any way.