GNG Drive Gen2
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lantice13
100 W
it's a very cheap mid drive kit...... so yep...... you want cheap/bang for the buck build, nothing can beat a direct drive hub motor in value. also the kit is rated for 450w-600w so should be ok if you stayed close to those figures. that's what I did with my 2015 gng gen 1. no breakdowns so far. knock on wood.....gman1971 said:
gman1971
10 kW
- Joined
- Oct 17, 2015
- Messages
- 976
Lantice, yep, this kit sucks more every day, so I might just get a dd rear hub and be done with it; but not sure what hub I can get that won't break the bank...
Amazingly, Jon is sending me a Gen1 freewheel, at no cost; which is shocking, well, maybe not considering I did put a good stink on PayPal.
And to make things better, the repaired 6mm end of the motor shaft broke off today, again, on my way to work; and I already ordered a 12mm hardened steel rod and a 12x15x10mm cage roller bearing: this motor is getting a solid hardened steel 12mm shaft across and it should be indestructible for the rated 22 amp, 48 volt; still amazed other people's motor don't snap in half, the construction is terrible.
This is the bearing that will go on the stator end of the motor:
http://www.bocabearings.com/bearing-inventory/Needle-Roller-Cage-Type/20779/12x15x10-K12X15X10
The original bearings are two 6x15x5mm; how can someone design a system with a 6mm shaft to hold a motor with insane torque is just beyond me...
G.
Amazingly, Jon is sending me a Gen1 freewheel, at no cost; which is shocking, well, maybe not considering I did put a good stink on PayPal.
And to make things better, the repaired 6mm end of the motor shaft broke off today, again, on my way to work; and I already ordered a 12mm hardened steel rod and a 12x15x10mm cage roller bearing: this motor is getting a solid hardened steel 12mm shaft across and it should be indestructible for the rated 22 amp, 48 volt; still amazed other people's motor don't snap in half, the construction is terrible.
This is the bearing that will go on the stator end of the motor:
http://www.bocabearings.com/bearing-inventory/Needle-Roller-Cage-Type/20779/12x15x10-K12X15X10
The original bearings are two 6x15x5mm; how can someone design a system with a 6mm shaft to hold a motor with insane torque is just beyond me...
G.
gman1971
10 kW
- Joined
- Oct 17, 2015
- Messages
- 976
And this is how you try fixing a shaft...
Thats a 40mm grade 12.9, 10mm socket bolt threaded to yield and loctited by the machine shop.
Since I found out that the 12mm cage bearing was out of stock, I settled for a 10mm solution, I know, its not as cool as a hefty 12mm but it should be a lot stronger than the crapo 6mm it replaces. Looks like someone in China doesn't know anything about how to design outrunner motors properly. Lateral deflection just doesn't magically disappear...
I will be installing three 10x15x4mm ball bearings on the back of the can (as opposed to just two), that should add a bit of extra rigidity for the lateral loads. With that said, ideally I would've liked to have the 12mm roller pin bearing and run a solid 12mm shaft end to end, but I think this might be a better solution for now... for now...
This kit is going to work, no matter how many crap parts I have to replace, re-machine or smash with a hammer... I am already too invested on this turd so I am going to make it so strong that the weakest link on the whole setup should be the mountain bike chain...
More updates as they happen... but for those who are thinking about purchasing a GNG? JUST DON'T!!!... move along, those are not the droids you're looking for...
G.
Thats a 40mm grade 12.9, 10mm socket bolt threaded to yield and loctited by the machine shop.
Since I found out that the 12mm cage bearing was out of stock, I settled for a 10mm solution, I know, its not as cool as a hefty 12mm but it should be a lot stronger than the crapo 6mm it replaces. Looks like someone in China doesn't know anything about how to design outrunner motors properly. Lateral deflection just doesn't magically disappear...
I will be installing three 10x15x4mm ball bearings on the back of the can (as opposed to just two), that should add a bit of extra rigidity for the lateral loads. With that said, ideally I would've liked to have the 12mm roller pin bearing and run a solid 12mm shaft end to end, but I think this might be a better solution for now... for now...
This kit is going to work, no matter how many crap parts I have to replace, re-machine or smash with a hammer... I am already too invested on this turd so I am going to make it so strong that the weakest link on the whole setup should be the mountain bike chain...
More updates as they happen... but for those who are thinking about purchasing a GNG? JUST DON'T!!!... move along, those are not the droids you're looking for...
G.
gman1971
10 kW
- Joined
- Oct 17, 2015
- Messages
- 976
Bike is back together; and working really well. The shaft with new bearings made the motor super-quiet; so I suspect the can was wobbling with the 6mm end.
Pics of the motor apart...
Those are 10x15 high quality bearings, the original ones were gritty as heck and they wobbled quite a bit. In order to do this I had to remove the indentation on the motor backplate to allow for four bearings (otherwise you're stuck with just two)
Overall it was worth it... motor is much quieter (even non oil-cooled) so it is promising and I suspect this will never break under normal use again...
Still with a busted freewheel, but that should be fixed soon since I ordered the Cyclone three chainring one... we'll see... not a huge need since I rarely pedal the bike when I commute covered in layers of clothes and a full face scooter helmet...
G.
Pics of the motor apart...
Those are 10x15 high quality bearings, the original ones were gritty as heck and they wobbled quite a bit. In order to do this I had to remove the indentation on the motor backplate to allow for four bearings (otherwise you're stuck with just two)
Overall it was worth it... motor is much quieter (even non oil-cooled) so it is promising and I suspect this will never break under normal use again...
Still with a busted freewheel, but that should be fixed soon since I ordered the Cyclone three chainring one... we'll see... not a huge need since I rarely pedal the bike when I commute covered in layers of clothes and a full face scooter helmet...
G.
gman1971
10 kW
- Joined
- Oct 17, 2015
- Messages
- 976
I got the Cyclone 3 chainring crankset/freewheel, and the quality is night and day vs the cheap GNG stuff. I should be able to hook this guy up tonight; so I am excited about it.
Bike has been working well with the new shaft and haven't had any of the warning sounds of the motor shaft going to snap... we shall see how it holds.
G.
Bike has been working well with the new shaft and haven't had any of the warning sounds of the motor shaft going to snap... we shall see how it holds.
G.
Joe T.
100 W
Joe T. said:
I figured I would reply to my own question. I recently pulled the trigger on a Gen2 for a customers bike. I am happy to say that it is just as fast as my belt reduction from 2013. It was about as bolt on as I could imagine. The only issue I have with the freewheel is it is based on a 64mm bolt circle in stead of the 104 which I feel would be better. I was about to build an adapter but after testing it out I saw no need to waste the time. It has great torque and is very quiet. Not silent but nice. I have had no chain slippage which was one of my fears. Top speed is 27 MPH depending on the charge. As before I simply used the parts that come in the kit with no controller tricks or mods. The only thing I made myself was a small spacer to get the chain tensioner to line up better. I installed the tensioner "wrong" IE pushing the chain down in stead of up under the drive sprocket because it didn't fit well the "correct" position. I road it that way and had no issues.
Since then I have built 4 other bikes using the same Gen2.
