Just a bit of feedback. Since doing the chain mod, other than changing the secondary chain to a halflink one (thanks rp3) I've had to do nothing to the drivetrain other than charge and ride. It works. Works great. Highly recommend doing it, especially if you use your bike for XC or Offroading.
GNG 450 brushless Mid Drive - Primary Drive Modifications
- Thread starter Cyclebutt
- Start date
jateureka
10 kW
t0me,
is your chain conversion still holding up ok?
is your chain conversion still holding up ok?
Secret1511
100 W
Hello,
Question how i get the adapter out of the big pulley?
Like to do the chain mod. I have a freewheel sprocket 65t
Question how i get the adapter out of the big pulley?
Like to do the chain mod. I have a freewheel sprocket 65t
Denisesewa
100 W
Unscrew it , mine was tight as hell though.Secret1511 said:
Denisesewa
100 W
Denisesewa said:
Here is a pic of what mine looked like apart >>
http://s1191.photobucket.com/user/Denisesewa/media/001-16.jpg.html?sort=3&o=23#/user/Denisesewa/media/001-16.jpg.html?sort=3&o=23&_suid=1375800984492045186691957480235
meelis11
100 W
Hi,
has anybody measured amperage/wattage before and after primary drive modifications - how much motor is consuming in full speed and no load (back wheel off the ground)
All are saying that stock belt tensioner is robbing lots of energy - exactly how much?
I actually doubt that removing secondary tensioner gives you much efficiency gains - If it does then how much?
* I am currently running it in stock configuration and tensioners are needed, because that big belt wheel and small freewheeling sprocket are wobbling a bit - tensioner keeps chain tight.
has anybody measured amperage/wattage before and after primary drive modifications - how much motor is consuming in full speed and no load (back wheel off the ground)
All are saying that stock belt tensioner is robbing lots of energy - exactly how much?
I actually doubt that removing secondary tensioner gives you much efficiency gains - If it does then how much?
* I am currently running it in stock configuration and tensioners are needed, because that big belt wheel and small freewheeling sprocket are wobbling a bit - tensioner keeps chain tight.
meelis11
100 W
Cannot believe that you can drop load by 100W just by removing tensioner - my test was showing about 50W difference: belt-on with stock tensioner vs belt-off.
That big belt sprocket was hard to turn when I first time took belt off so I had to fix it (took freewheeling sprocket off and filed that tube-shaped spacer shorter about 0.5-1mm what is behind freewheel sprocket - that removed tension/resistance in that shaft)
Maybe I can make new test with photos to show difference between belt-on and belt-off. Now my motor consumes about 130W when in full speed and is driving belt but chain is off. When it drives off-the-ground bike wheel, it is about 150W
Meelis
That big belt sprocket was hard to turn when I first time took belt off so I had to fix it (took freewheeling sprocket off and filed that tube-shaped spacer shorter about 0.5-1mm what is behind freewheel sprocket - that removed tension/resistance in that shaft)
Maybe I can make new test with photos to show difference between belt-on and belt-off. Now my motor consumes about 130W when in full speed and is driving belt but chain is off. When it drives off-the-ground bike wheel, it is about 150W
Meelis
speedmd
10 MW
Jack shaft has issues at least on the one I got. Bearing spacing was too tight causing compression of the outer races onto the balls. Shaft stack length (bearing shoulder to opposite side shoulder) was shorter than the support stack distances. When shaft / hub retainer nuts were tightened down, the shaft bound up and was overly stiff. Basic engineering tolerance error having the inner support spacers .1-.2mm too long and fighting this with ball compression. When I corrected this it spun like a bike wheel. The new solid support structure should be much better at holding tolerance. The way mine was, it would have been most likely been over a 50 watt loss just in the shaft.
Just a quick update on my primary chain mod.
I changed my secondary driven sprocket to a 48 and now I've broken the primary chain twice. Seems the 04b 6mm chain isn't up to it anymore.
Also, its difficult to get in Australia. #25 chain however seems to be available though and is 30% stronger from what I've found spec's wise. So I'll be re-modifying to take that chain (and try to up the ratio a little on the primary).
Just need to find a #25 10mm bore 11t sprocket. TNT don't have them in stock and I haven't had any luck finding one locally yet.
The drive sprockets I've seen use a through pin. Has anyone just modified one like that (tapped those holes) to use grub screws instead? Theoretically I think that'd work? I'd rather not drill through my output shaft if I can avoid it.
I changed my secondary driven sprocket to a 48 and now I've broken the primary chain twice. Seems the 04b 6mm chain isn't up to it anymore.
Also, its difficult to get in Australia. #25 chain however seems to be available though and is 30% stronger from what I've found spec's wise. So I'll be re-modifying to take that chain (and try to up the ratio a little on the primary).
Just need to find a #25 10mm bore 11t sprocket. TNT don't have them in stock and I haven't had any luck finding one locally yet.
The drive sprockets I've seen use a through pin. Has anyone just modified one like that (tapped those holes) to use grub screws instead? Theoretically I think that'd work? I'd rather not drill through my output shaft if I can avoid it.
Denisesewa
100 W
Yep, I drilled and tapped the drive sprocket, filed flats on the shaft for the screws to sit against and have had no problems, Try to source "Diamond" #25 chain , best specs of any #25 I could find, If I remember right its availible through combat robot sites.t0me said:
Nice one thankyou.
Ran into some problems today after fitting some new 04b chain (till the new 25 chain and sprockets arrive).
My controller died...
I'll post in the main GNG thread about it, some weird stuff happening with the "spare" controller I had.
Ran into some problems today after fitting some new 04b chain (till the new 25 chain and sprockets arrive).
My controller died...
I'll post in the main GNG thread about it, some weird stuff happening with the "spare" controller I had.
Denisesewa
100 W
I used two 8 x 32 , one each side
Dear Forum members,
Apologies for tagging on to a previous post, maybe somebody can point me to a different location. I bought a 450w 48V mid drive kit from Hong kong. I am very happy with it and I mounted it and initially ran it without any problems on my hard tail mountain bike.
Unfortunately I didn't mount the cables in the yellow motor to controller box. The cables were not tightened together and before I had noticed the problem the motor stopped working. After analysis I saw that the yellow cable was severely melted and inside the yellow box there was plenty of burning & the screws were corroded.
I have re-stripped the wires and reconnected them via a normal screw in electrical connector. All is connected up properly but the motor will not run. I am concerned that I have somehow damaged the controller, otherwise I do not know what is wrong.
Could somebody offer some advice, is there way that I can proof the controller and motor to see if they are ok. I have heard about hall sensors on the kit could I have damage one of them also ?
Many thanks in Advance
E-Vince
Apologies for tagging on to a previous post, maybe somebody can point me to a different location. I bought a 450w 48V mid drive kit from Hong kong. I am very happy with it and I mounted it and initially ran it without any problems on my hard tail mountain bike.
Unfortunately I didn't mount the cables in the yellow motor to controller box. The cables were not tightened together and before I had noticed the problem the motor stopped working. After analysis I saw that the yellow cable was severely melted and inside the yellow box there was plenty of burning & the screws were corroded.
I have re-stripped the wires and reconnected them via a normal screw in electrical connector. All is connected up properly but the motor will not run. I am concerned that I have somehow damaged the controller, otherwise I do not know what is wrong.
Could somebody offer some advice, is there way that I can proof the controller and motor to see if they are ok. I have heard about hall sensors on the kit could I have damage one of them also ?
Many thanks in Advance
E-Vince
Attachments
Hi guys
Does anyone know of bolt on tensioners or rollers etc. for the primary drive? Im using #25 chain and its loose on the 65T and 13T sprockets
There are a few possible mounting holes already on the stock GNG chain reduction motor (where the protective guard bolts onto)
Perhaps I could use those to mount.
However, I dont have access to a garage o anything to do homemade modifications, so Im looking for a bolt on solution
Does anyone know of bolt on tensioners or rollers etc. for the primary drive? Im using #25 chain and its loose on the 65T and 13T sprockets
There are a few possible mounting holes already on the stock GNG chain reduction motor (where the protective guard bolts onto)
Perhaps I could use those to mount.
However, I dont have access to a garage o anything to do homemade modifications, so Im looking for a bolt on solution
Overclocker
10 kW
chain conversion done. 80T and 11T #25 sprockets from electricscooterparts.com
hacked the belt cog into a "spider"
#25-HD KMC chain
Overclocker
10 kW
LR upper sheets
Cyclebutt
100 W
Good work! I put my GNG on the back burner while you guys figured out how to correct the inherent problems associated with this kit. I LOVE the design but hate the execution. With my LightenRods sheets and a little "mod" work I may have this project back in the running before too long. Please keep those efforts published here so we all don't have to reinvent the wheel. Thanks to all! Oh, and photos! Please share your photos! Cheers!
meelis11
100 W
Here is my stock belt drive modification - only new part you need is new shorter belt (460mm length instead of 475mm)
http://endless-sphere.com/forums/viewtopic.php?f=6&t=68488#p1032663
http://endless-sphere.com/forums/viewtopic.php?f=6&t=68488#p1032663
Overclocker
10 kW
so meelis hows the reduced tooth engagement working out for you?
