New GNG mid-drive 2500W

[slowhands]

Incredible. This GNG failure saga goes on and on and on. I think they designed it to minimize cost, not realizing the consequences. It does still sell. For my money the Cyclone stuff looks much better, but Cyclone's marketing is terrible.

Now the question is have they learned anything for the HD version. Do note that they use the wider 25mm belt, ISIS crank from Taiwan, and a few other details like that. But it still looks like thin sheets, unless they are stainless or something, and not adjustable either. The chain looks like the same crap 219 chain (which may still be OK, cuz it is way stronger than needed). Time will tell. I'm hoping they somehow step beyond their traditional low quality offering and make a decent product.

I admit to a certain morbid fascination with the saga of this product line. At a certain point you think, it can't get any worse. Yet... it does.

 

[gman1971]

Incredible. This GNG failure saga goes on and on and on. I think they designed it to minimize cost, not realizing the consequences. It does still sell. For my money the Cyclone stuff looks much better, but Cyclone's marketing is terrible.

Now the question is have they learned anything for the HD version. Do note that they use the wider 25mm belt, ISIS crank from Taiwan, and a few other details like that. But it still looks like thin sheets, unless they are stainless or something, and not adjustable either. The chain looks like the same crap 219 chain (which may still be OK, cuz it is way stronger than needed). Time will tell. I'm hoping they somehow step beyond their traditional low quality offering and make a decent product.

I admit to a certain morbid fascination with the saga of this product line. At a certain point you think, it can't get any worse. Yet... it does.

Yep, it can always get worse... and 2500 out of a GNG is like asking a pig to fly... sure, if you throw it with enough force it will fly, but the landing won't be pretty...

Just don't buy this crap and look elsewhere.

G.

 

[markz]

Didnt want to hijack this thread, so I posted my own here,
https://endless-sphere.com/forums/viewtopic.php?f=28&t=74343

 

[emaayan]

Whats the breakdown then in terms of quality?

Lightning Rods
AFT
Tangent - RC Motor
EGO
Bafang
Cyclone
GNG

i have to admit i've rarely seen anything about tangent -rc motor, but if you include the an rc one, don't forget the da-vinci drives .

also don't forget about ecospeed (you can say it costs alot, but so does tangent and ego )

btw it would also interesting to compare just the MOTOR between all those drives. after all gng best selling point was the motor in the first place.

 

[fourbanger]

I was just thinking about buying the new GNG G2 kit. I'm kinda glad I read this post.

 

[emaayan]

G2?

 

[gman1971]

G2 = Gen2, its the "newer" GNG middrive made from a converted hub motor.

The GNG Gen2 2015 will pull around 1200 watts on the stock controller, and that without any amp regulation at the motor, so you get full power on the slightest jerk of the throttle and that pretty much will snap everything that isn't designed for that kind of abuse.

The only other issue I had, expected BTW, was the shaft key that holds the planetary clutch to the main shaft also snapped off, so I made another dutchman round key and the motor is back in business; and now probably good for a lot more power than the rated power so it will be more durable and reliable.

After about 400 dollars worth of labor/work/parts my GNG G2 is now rock solid.

G.

 

[robocam]

Has anyone tried this new mid drive? What are your thoughts on it? I have the 2015 48V belt model, and I really like it but I had to replace the crankset with a Cyclone unit because the crank freewheel failed.

What I like about this new "Lightningrodded" version is the 33.3:1 reduction so that I can at least try to pedal, though I did slightly increase the ratio on my kit by ordering the cyclone with a 48T chain ring (vs 42T stock).

Is there anything about this kit that raises red flags or that I should be aware of? Are there other kits I should consider? This one seems like a really good deal at ~$600. I don't plan to run it at "modded" power levels.

 

[markz]

I do not see the 2500W unit for sale on their website, just their Premium 2000W belt drive which states in the specifications it can handle 2500 and their 1500W.

 

[gman1971]

Has anyone tried this new mid drive? What are your thoughts on it? I have the 2015 48V belt model, and I really like it but I had to replace the crankset with a cyclone unit because the crank freewheel failed.

What I like about this new "Lightningrodded" version is the 33.3:1 reduction so that I can at least try to pedal, though I did slightly increase the ratio on my kit by ordering the cyclone with a 48T chain ring (vs 44T stock). Does this increased 33.3:1 reduction have a very noticable real-world effect? Can I really now pedal along with the motor, and if I can, what voltage should I limit my battery to so that it doesn't spin the crankset too fast for pedaling? Another thing I'm wondering about is if this increase in torque will cause chain skipping.

Is there anything about this kit that raises red flags or that I should be aware of? And lastly, are there other kits I should consider? This one seems like a really good deal at ~$600. I don't plan to run it at "modded" power levels.

Also, one thing I've been wondering about is the 100W number people keep tossing around regarding the power wasted in the idler pulley of the old design. It seems to me that the 100W figure might be accurate if the unit is under no load, as it was tested on a bench right? Once the belt is loaded, it would seem that the extra belt-wrap would waste less power since the belt is slightly stretched under load. In any event, I'm all for an increases in efficiency. I've just been curious if it's really 100W in practice.

Just get the Cyclone 3000W for ~380 bucks from Luna Cycle... it will blow away anything GNG made, and it won't snap in half after 150 miles...

G.

 

[robocam]

Wow, thanks for the suggestion. That Cyclone looks like a great alternative at an awesome price, but it looks like it would spin the crank faster than the average human can pedal. The main reason I'm interested in the new GNG is because of its 33.3:1 reduction. The Cyclone has a 4.9:1 primary reduction vs the original GNG's 6:1 primary reduction, so if the Cyclone's motor spins as fast as the original GNG's motor, I definitely wouldn't be able to pedal along with it. The freewheel sprocket on the Cyclone also appears to have more teeth than the one on the original GNG, further reducing the final ratio. I already have a 48T chainring on my Cyclone crankset, and there's no room for a larger chainring or it will hit the chainstay.

Just get the Cyclone 3000W for ~380 bucks from Luna Cycle... it will blow away anything GNG made, and it won't snap in half after 150 miles...

G.

 

[gman1971]

I was going to say get the larger 48-44T crank but..., I run mine on 48V (12S lipo) with a 44T drivechain and cadence is about 115 at 30mph; which is perfect for me since I want to train faster cadence (my usual before was around 90, me wants 100+) for when I go back to my road (non ebike) this spring.

You could also overdrive the motor to get a lower cadence; so instead of doing 30mph on 8th gear at 120 cadence, you do 30mph on 10th at 95cadence.

At any speed above 25 mph on a mountain e-bike your pedaling input becomes exponentially negligible; and the amount of torque required to propel the bike forward at human pedaling RPMs will be massive and you'll snap chains left and right ... at that point if you want a long lasting mid drive ebike you need to chose high RPM, even if you can't pedal the bike.

You could also use those "power mode switches" make the first two as pedal friendly, but the third one is motorcycle only mode.

Again, IMO you should always go for higher RPM and gear down to get the torque than for opt for low RPM and massive torque and then gear up...

G.

Wow, thanks for the suggestion. That Cyclone looks like a great alternative at an awesome price, but it looks like it would spin the crank faster than the average human can pedal. The main reason I'm interested in the new GNG is because of its 33.3:1 reduction. The Cyclone has a 4.9:1 primary reduction vs the original GNG's 6:1 primary reduction, so if the Cyclone's motor spins as fast as the original GNG's motor, I definitely wouldn't be able to pedal along with it. The freewheel sprocket on the Cyclone also appears to have more teeth than the one on the original GNG, further reducing the final ratio. I already have a 48T chainring on my Cyclone crankset, and there's no room for a larger chainring or it will hit the chainstay.

Just get the Cyclone 3000W for ~380 bucks from Luna Cycle... it will blow away anything GNG made, and it won't snap in half after 150 miles...

G.

 

[robocam]

Thanks for the suggestions. One reason I would prefer not to overdrive the motor is because I want higher efficiency. I want to keep the motor spinning as fast as possible, but I want to help out by pedaling as well, so that's where the desire for the 33.3:1 ratio comes from. I usually don't ride at high speeds, so hopefully my pedaling will help my battery last longer. But you're right about the high load on the chain. I'm concerned about skipping because I think I've already experienced that with the stock 2015 GNG belt mid drive while towing a trailer with 4 kids in it.

...You could also overdrive the motor to get a lower cadence; so instead of doing 30mph on 8th gear at 120 cadence, you do 30mph on 10th at 95cadence.

At any speed above 25 mph on a mountain e-bike your pedaling input becomes exponentially negligible; and the amount of torque required to propel the bike forward at human pedaling RPMs will be massive and you'll snap chains left and right ... at that point if you want a long lasting mid drive ebike you need to chose high RPM, even if you can't pedal the bike.

You could also use those "power mode switches" make the first two as pedal friendly, but the third one is motorcycle only mode.

Again, IMO you should always go for higher RPM and gear down to get the torque than for opt for low RPM and massive torque and then gear up...

G.

 

[crossbreak]

Km 0.53 Nm/√W

for the belt chain motor http://www.gngebike.com/belt-chain-motor

This means you need the reduction ratio of 6.7:1 to get it to a level where it could climb some mild hill. This is the 80T/12T #219 chain option. The #25 option is absolutely senseless. The 1500W rating seems to be overrated. From my calcs this looks more like 1000W.

With this reduction it should be similar to a MAC hub motor, the Kv should be similar to 8T MAC windinng

 

[robocam]

Nevermind, I just realized I misunderstood.

 

[emaayan]

i wouldn't bother trying to rate this motor, the same motor will appear as 450,500,700,1000 and now 2500 watts kits of gng and others have been known to run it higher,
that's what spurred the entire aftermarket changes of e-s and what caused L-R to be born, (l-R later used the same motor but only 10 mm thicker and rated it as 3000w, the "original" rating was 500)
so it's pointless, i myself have used it in 2000w, and reached speeds of 55 kph, i'm currently running it on 1500w and going at 45 kph.

there's no way a single reduction can be sufficient fo this motor, for my money reduction around the 20:1 more or less would be sufficient.
the main problem is how to fit a primary reduction that would be both small and powerful enough to make it more compact then the cyclone. (or maybe match it for a cyclone)

that's why i thought about planetary gears. such as this one : http://products.matexgears.com/item/all-categories/planetary-gears-torque-range-301-11-478-in--lbs-/5mef
it's input can have adapter to the 12mm shaft, and you could create a plate to be bolted to motor.the other problem is finding a shaft and a housing the will hod the shaft via bearing,
all of them together may place the motor at the same thickness of the cyclone.

 

[gman1971]

I wouldn't bother with GNG at all... thats to put it right there. The quality of their kits is arguably poor at best.... but their customer service? Let me tell you, their customer service is UTTER SH*T for anything, and warranty claim? well, its effectively non-existant; best of all is that when you get their attention they will still nickel and dime you every step of the way; with little sad stories like "my poor roomate pays for his own food and rent and the air fare comes from his pocket, but hey he packed everything real well for you.. could please pay the shipping to help this poor roommate...etc etc" Give me a break!!!
My "brand new" GNG Gen2 kit broke a motor shaft ater 140 miles running on the stock 22amp controller at 48V, while commuting to work; I wasn't even offroading or doing anything stupid; yet they wanted me to pay for the air freight for the shaft... which should've never broke at the stock controller power on a daily commute to work. Then the freewheel on the crank failed too, had to get paypal involved with a serious dispute so they would send me a better crank freewheel.... then the chain tensioner snapped and the chain turned the whole drivetrain into a pretzel... then the one-way clutch failed, throttle stopped working... seriously, Bafang or Cyclone seem have a far better reputation than GNG... plus you can buy replacement and upgrade parts for these kits from US distributors directly... Look at Youtube and compare the number of successful Bafang videos vs. the number of GNG videos... that should end the argument right there.

G.

 

[emaayan]

well personally i bought the 2015 kit because of the motor itself, i agree that the shaft breaking is a red line but i half expected the rest to brake ,but i knew looking at the motor itself i had hopes to replace them with something better.
And since i live in israel i pretty much have to rely on myself and not support from anyone

the bafang 750w i heard about had some major faults on it's own, mainly blown mofsets and penut butter nylon gears. and the fact you had to get a proprietary chain ring. so it's main selling point is stealth and quiet

I view gng as maker's baseline.

 

[gman1971]

The motor of the Gen1 has good reviews, but that is not a GNG motor: GNG didn't build the motor they simply packaged it as GNG with their substandard kit... but why bother with just the motor when you can have a complete kit that works very well? This is my point on Cyclone... okay, their kits are not the pretty mid drive as the Bafang, but 3000 watts out of the box in a reliable package for ~340 dollars is a deal... the trick is to not have to mess with this every day... all I do now is clean stuff and recharge batteries... and ride my bike.

The BBS02 has issues, agreed; but the plastic gear is a replaceable item that you can readily buy; and when BBS02 is run at stock power level from what I've learn they rarely failed. If you try to "hot rod" the thing sure, then the BBS02 would fall apart... at stock power it was fairly reliable. The GNG was ran at stock power, yet it failed.

G.

well personally i bought the 2015 kit because of the motor itself, i agree that the shaft breaking is a red line but i half expected the rest to brake ,but i knew looking at the motor itself i had hopes to replace them with something better.
And since i live in israel i pretty much have to rely on myself and not support from anyone

the bafang 750w i heard about had some major faults on it's own, mainly blown mofsets and penut butter nylon gears. and the fact you had to get a proprietary chain ring. so it's main selling point is stealth and quiet

I view gng as maker's baseline.

 

[Sean9002]

well personally i bought the 2015 kit because of the motor itself, i agree that the shaft breaking is a red line but i half expected the rest to brake ,but i knew looking at the motor itself i had hopes to replace them with something better.
And since i live in israel i pretty much have to rely on myself and not support from anyone.

I thought Revolt motors are made in Israel?

 

[emaayan]

Revolt motors?

 

[goa604]

http://www.revolt.org.il/

 

[olivier38]

Hello to Endless community!

Some people are asking some feedback on the new GNG 2500W kit. I just bought this kit and tested it for 2 trips.
Well, compared to the GNG chain reduction kit (installed on my "week bike") the quality is excellent. No chain slip, no wobbling effect of cranck, chain tension is perfect.
For instance the BB mounting and upper mounting are strong: no movement of motor when starting.
Moreover, the controller provides high RPM fitting the big reduction ratio => with pedal assist, top speed is about 50km/h.
The torque is enormous too, (For comparison, it's better than gear reducted hub motor as I can select the good bicycle bracket speed). I'm living near mountains and i can say that climbing ability is excellent. On flat road, when throttle is turned to the max, the bike tends to make rear wheel (sorry for my poor english level ).
the belt is very wide (25mm), well tighten and seems to be very strong. But It needs to be confirmed with time.
I use a Lifepo4 battery 16s 10Ah+BMS 60A/150A, in a backpack, the range is good: it easily allows a trip of 25km with hills and with electrical assistance.
Now, about the aesthetic criteria, the orange and alu color are pretty well and gives very look to the bike.
at the end, GNG provides an excellent and affordable mid drive kit!

 

[robocam]

Thanks for posting. Could you show us pictures of your bike?

Hello to Endless community!

Some people are asking some feedback on the new GNG 2500W kit. I just bought this kit and tested it for 2 trips.
Well, compared to the GNG chain reduction kit (installed on my "week bike") the quality is excellent. No chain slip, no wobbling effect of cranck, chain tension is perfect.
For instance the BB mounting and upper mounting are strong: no movement of motor when starting.
Moreover, the controller provides high RPM fitting the big reduction ratio => with pedal assist, top speed is about 50km/h.
The torque is enormous too, (For comparison, it's better than gear reducted hub motor as I can select the good bicycle bracket speed). I'm living near mountains and i can say that climbing ability is excellent. On flat road, when throttle is turned to the max, the bike tends to make rear wheel (sorry for my poor english level ).
the belt is very wide (25mm), well tighten and seems to be very strong. But It needs to be confirmed with time.
I use a Lifepo4 battery 16s 10Ah+BMS 60A/150A, in a backpack, the range is good: it easily allows a trip of 25km with hills and with electrical assistance.
Now, about the aesthetic criteria, the orange and alu color are pretty well and gives very look to the bike.
at the end, GNG provides an excellent and affordable mid drive kit!

 

[emaayan]

ok, can you do a weekly drip and get back after 2 weeks?