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

[d8veh]

D8VEH-
"25 amps using a KU93 9FET controller ..massive torque .. didn't even slow down as i changed up through the gears to fourth" . Could you share more data on your ride, sounds great. Were you using CA or ammeter, or relying on controller rating, do you have a auto fuse inline, did you check temps? How long was test climb, sufficient to get to steady state temperature, did controller or motor seem hot? Thanks for your post.

I didn't use a CA. This controller has 30% soldered shunt. I took it from another bike that has a CA, so I know the max current is 25 amps. The tests I did were on a 50 meter 15% (measured) hill. I don't have a fuse because the BMS in the battery limits current.

I took it out for a 15 mile ride yesterday. Unfortunately the battery BMS kept tripping if I held full throttle for more than about 10 seconds, so I couldn't test it properly, but what I can say is that in the low gears it gives the impression of massive torque, but on the open road in higher gears, it doesn't feel so powerful. It was good to get significant acceleration when going downhill at 30mph. Speed on the flat was about 22 to 25 mph, but difficult to be sure because of the BMS cutting the power after 10 secs. The last 5 miles of my ride were continuous uphill, sometimes steep. I could only use half power because of the BMS. The controller was a bit warm when I got home and the motor was more or less cold. I'll try again tomorrow with lipos so that I can use full power all the time.

When the system is new, it takes a few miles for the waxy grease to come out of the chain, so you have to keep adjusting the tension otherwise it's noisy and could jump. I oiled mine after about 10 miles and now it's settled down and is very quiet and no longe needs frequent adjustment. I think it will be important to keep the motor chain properly lubricated.

On the open road the system is fairly quiet. During acceleration from a start, it has slightly more noise than a geared hub motor in similar circumstances. At 15mph and above, the wind noise drowns out the motor noise.

 

[d8veh]

I've been out on my bike again today. Now I'm using 12S lipos at 25 amps. It's totally insane compared with the geared hub-motors I'm used to. In first gear I couldn't get off my neighbour's driveway without wheelying because it's uphill. With my 100kg on a fairly heavy bike, it's doing 22mph up a slight hill. Downhill you can go as fast as you like. I nearly got 40mph on a long medium down-hill. I did about 15 minutes of mainly full throttle and the motor hardly got warm. It certainly has torque, power and speed. The only question is how long the chains and gears will last. It has to be the best bang-for-buck kit by a long way.

 

[christerljung]

This is an anti-twist mod i installed today. The force of 72v seem to bend the hole unit. This is an idea im gonna try now.
Had to do it in brass to keep up the steam-punk feeling of this fantastic mechanics.
Btw, the 2:nd idler mod keep doing a good work, no belt issue so far.

 

[snellemin]

This setup has a lot of torque. Broke my chain today riding over grass on just 12s. My wife is surprised how quiet the setup is. Ordered me a wipperman chain from Amazon and bike is will be down untill Tuesday. Bummer.

 

[eramachinery]

Bro , Need to know from the professional , is the GNG motor brush less motor compatible with crystalyte 48v 45A controller with or without hall sensor ?
how about the crystalyte 72v 45A controller with or without hall sensor ?
Glad to hear from you guyz , many thanks!~

 

[wavezz2k]

Now have my 2nd GNG. Couple observations- Shipping & BB Bearings.
There's 3 options. Forget all but the top AIR Post EMS, pay the extra $$.
From HK to California, ship out on 3rd, arrived morning of the 5th. Box was perfect, not a scratch. First box shipped regular expedited took about 12 days, but was destroyed through regular post (literally had parts broken, & parts lost from falling out of the busted box). I requested double boxed. Your mileage may vary.

EDIT - UPdate. Just don't want someone ordering the wrong bearings - doh. the BB bearing set is labeled a 6200
6002 2RS Double Sealed Bearing 15 x 32 x 9 ; The width of the bearing set should be 9mm per most bearing mfg. BUT, it's not. So, I believe the bearing is different than the stamp, because the width is about 10mm.
The extra 1mm, kinda matters. Long story short, you'll have to have the bearing 'in hand' when shopping for replacement. Strangest thing of that sort ever.

BB Bearing. Truth is, some parts are inexpensive. The BB bearing is taking a lot of load, rather than change it out again later,

check out this ABEC 3 precision sealed bearing, bought 4 with shipping for $10. Before doing the BB work, you might wanna consider splurge $1.66 US for upgrade bearings.
DOES NOT FIT -> http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=150564792184
One of my bearings was 'noisy/sticky' don't believe it last, never know, pitched it.

 

[christerljung]

Wavezz: Thanks for information!! Was just considering a second GNG and cancel my bafang order for my electric commuter.
Those bearing is a must have. Thats for sure, things gonna break down fast with all this torque and watts.
Going for my first longer ride now. 25km. Will report back later tonight.

 

[bzhwindtalker]

Got mine spinning too, I lack some tools to get it on the bike (150mm travel Freeride bike), will be done next week.

 

[christerljung]

Did a 30km trip to the countryside today GNG made a good job, with some pedaling in the beginning when i was crossing the town. It was mixed asphalt, gravel end wood-track all along. Half the ride it was 1700m long 14% upphill gravel road in the wood, throttle was maybe at 80% - 100%, at the top of the hill motor felt a little hot. In the end of the journey i thought chain started slipping coggs or maybe freewheel breakdown? But later at home i saw, it was just the cassette-nut that had come loose.
Belt starts to look a little ugly but is still doing what it should.
30km pretty hard riding emptied the 10Ah 72v lipos.
map of ride:http://kartor.eniro.se/m/9yTFr
This is an awesome kind of cycling.

 

[d8veh]

Bro , Need to know from the professional , is the GNG motor brush less motor compatible with crystalyte 48v 45A controller with or without hall sensor ?
how about the crystalyte 72v 45A controller with or without hall sensor ?
Glad to hear from you guyz , many thanks!~

I think 48 amps is too much. There's a huge amount of torque with 25 amps. If the GNG unit can take it, your final drive may not. Why don't you try the 22 amp controller that comes with the kit?

 

[snellemin]

I put the GNG motor kit on this prodigy bike I put together and it's just doesn't work on this frame. The torque just pulls the rear part of where the cassette is to the right under load. Then my chain jumps gears when I'm using the 12T gear, but not so much with the bigger gears. I'm going to swap the system over to a different bike. The bike is still light and well balanced though.

 

[litespeed]

That's a good looking set up. Too bad it doesn't do what you want it to. Do all the GNG kits come all aluminum now?

So is 50 kph or 31 mph on 75 volts the top speed out of everyone here? If I could get closer to 40 mph I'd be all over this.

Tom

 

[spinningmagnets]

If your commute is pretty flat, you can easily gear it up to 40-MPH. Get a rear gear cassette with an 11-tooth small sprocket, and maybe get a larger chainring listed earlier in the thread (stock is 44T, 52T is easily available)

 

[wavezz2k]

<christerljung » Sat Oct 06, 2012 2:06 pm, Did a 30km trip .. >> That's what I'm talking about. Light, agile, 30km, with xlnt climbs. Perfect. Nice post.
Clearly GNG hardware is still evolving, but it's the 'sweet spot' for my power vs weight req'mnt. Personally, don't need 40mph on a MTB, get a Suzuki DRZ 400 SuperMoto for those days.

Temps checked on bench test. 2nd unit.
http://youtu.be/3RCyyihMYIk

Don't have Turnigy amp or CA or a shunt installed, so don't know for sure amps pull (meter is in the mail). Ran the GNG at 90% throttle on the bench for 2+hours using an industrial 48v 9ah power supply. Recorded the temps on belt, bearings motor & controller with Laser IR. This is free running only, no external load. Controller was only 81 degree, not even warm. Motor, belt, and bearings were 'hot', 130 degree plus (55c) , hot as far as my personal scale. Motor leads, to me, are kinda small for 1kw, though were not warm. Testing room was 70F ambient (21c), fairly cool Belt measured 134 F at points. IR sensor only reads F on video. I elected a bench test run before mounting up.

Some may call this a 1kw system, not sure I'd buy that. At 9amp limit, 90% throttle for an hour, it's getting hot enough that personally wouldn't want to push it harder at full 100% duty cycle. Factory calls it a 450watt. Short bursts 1kw, for sure, but steady state at 1kw load would cause much higher temps, to the point of degrading bearings, belt, or windings - just opinion 100% duty at 1kw, parts would toast.

As aside, the silver is clear coat steel, mild alloy. In aluminum, this plate gage would flex excessively. Mount Brackets are unchanged from black to silver version, no changes. Silver rev - the pulley cover has the clear plastic on the pulley, not on the pulley plate. Black rev - the plastic falls off of the plate. All brackets are ferros magnetic. Best approach of the pulley plate is to add extra bonding in order for the black rev which has clear plates over the large pulley and drive pulley, then it helps keep clothes/bits/some dirt out of the belt.

(Rev) Minor update -
Temp log with thermocouple (1/2 degree accuracy) shows the ambient was 65 F, and motor case temp was 146 F - that's pretty hot, at about 35 minutes.

 

[bzhwindtalker]

I found out my BB is too wide to fit the motor, there is 5mm to remove... The big hits needed that mod too, how did you do it?
Can't wait to try this out... and get an e-bike rolling again.

 

[christerljung]

@Bzhwindtalker: Yes, the Bighit was too wide at BB. I turned it upsidedown and had the angular grinder gently cutting threw. Its very easy to damage the BB, cutting too much or destroying the threads. Be careful. You can put the special BB nut inside the BB, do the cutting and take the nut out slowly to "repair" the surface were grinder has meltet aluminium.
I'm anxious to hear your opinion about this kit compared to your previous impressive builds.

 

[tri-lobe]

Hello members,
I'm getting the impression from users of this kit that there is some flex in the mount brackets...ie 2.5mm thick..multi-piece..arrangment....
I felt that I could flex mine quiet easily on the bench...just my personal opinion...

I have made my mounts out of 3mm plate....full circle both l/h and r/h with 6 holes for motor mounts and 6 holes to mount to swing arm should I need extra rigidity.....I might only use 3 at the end of the day...

I'm of the opinion that if the motor mount ain't rigid then everything else will turn to crap....ie...belt drive,..chain drive...and so forth....

Why put 72volts into something into something thats bending....that will just give grief and frustration.....

I hope my photo shows what I'm trying to explain.......

 

[litespeed]

If your commute is pretty flat, you can easily gear it up to 40-MPH. Get a rear gear cassette with an 11-tooth small sprocket, and maybe get a larger chainring listed earlier in the thread (stock is 44T, 52T is easily available)

I know I want to run the crap out of what ever I get so I'm not sure if this is the best for me. I just don't want to have to re engineer a kit and with the pot luck on whether you actually get a good one or a bent up/non working kit. I'm getting crabby in my old age with being a beta tester. I think I'll stick with the hub motor till I can afford the Ego kit. Good luck to all who have one or plan on purchasing one in the future.

Tom

 

[eramachinery]

d8veh :I think 48 amps is too much. There's a huge amount of torque with 25 amps. If the GNG unit can take it, your final drive may not. Why don't you try the 22 amp controller that comes with the kit?

Thanks d8veh !~ i just wanna to know whether the GNG brush less motor compatible with the crytalyte controller ?
Btw 22 amp (comes with gng controller) is enough between 0- 30 degree steep, if 40-45 degree step up hill , the gng controller cant handle it ~
is there any other way to make it more tourqe in order to climb 40- 45 degree ? my hub gear used 34T , but still need human power to help climb it ?

Thanks

 

[Rassy]

is there any other way to make it more tourqe in order to climb 40- 45 degree ?

Do you really mean 45 degrees? That would be a 100% grade. Even a 45% grade is way too steep for almost anything.

 

[d8veh]

d8veh :I think 48 amps is too much. There's a huge amount of torque with 25 amps. If the GNG unit can take it, your final drive may not. Why don't you try the 22 amp controller that comes with the kit?

Thanks d8veh !~ i just wanna to know whether the GNG brush less motor compatible with the crytalyte controller ?
Btw 22 amp (comes with gng controller) is enough between 0- 30 degree steep, if 40-45 degree step up hill , the gng controller cant handle it ~
is there any other way to make it more tourqe in order to climb 40- 45 degree ? my hub gear used 34T , but still need human power to help climb it ?

Thanks

If you lower the gearing enough, it'll go verical, but not very fast.

 

[eramachinery]

RAssy : Do you really mean 45 degrees? That would be a 100% grade. Even a 45% grade is way too steep for almost anything

yup ..i've test the hs4080 with crytalyte 72v 48A , the result can climb 40 -45degree without human power

but with the GNG motor + GNG controller + lower geared 34T ,need a bit human power to help cllimb it ...

so i wonder whether the crystalyte controller sensor / sensorless compatible with gng motor

thanks

 

[spinningmagnets]

yup ..i've test the hs4080 with crytalyte 72v 48A , the result can climb 40 -45degree without human power

Pics or it didn't happen. Have a string and a weight in the pic to show the direction of gravity.

I re-labeled the title 1000W instead of the sales web-sites "450W" because 48V X 22A (the verified max amps of the stock controller) = 1056W. Depending on load, its possible that it might get too hot, but the stock kit does put out 1000W.

 

[amberwolf]

Yellow is what you probably are talking about, green is what you say you've ridden up. I don't know of many things that can ride up something like that, and I don't know any ebikes that could.

 

[litespeed]

This one gets close but not on the budget side.......http://www.ego-kits.com/en/ego-kits/

Tom