Crank Drives! (again)

£2.49

Pedelecer
Jan 3, 2013
31
0
I ride a heavy 3 speed cargo bike and carry about 15-25kg on the front.I would also like to haul about 50-60kg behind the bike on a trailer every now and then and I would have to go up some reasonable size hills on my travels.
I weigh about 95kg so all in all what ever I fit needs to have some bite!
My question to all you experts out there is...... If you were riding my bike which crank drive would you choose?
And yes I know I need to lose some weight :eek:

Oh and the reason I want a Crank Drive system is because my bike has front roller brakes and a rear back pedal break.
Forgot to say I'm not looking to go fast just want to get up them hills!
 
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jackhandy

Esteemed Pedelecer
May 20, 2012
1,820
323
the Cornish Alps
I can only offer a reasonably informed opinion on the GnG 250w crank drive kit, as that's the only one I've fitted & ride:

It's not powerful enough for what you want, it's quite noisy & is a bit of a Watt-Hog.

It's great fun to play with though :rolleyes:
 
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Deleted member 4366

Guest
There's a very limited choice of crank-drive kits. The cheapest and easiest to fit, whilst having sufficient power for what you want is the GNG Gen1.
mid 450W (brushless)
There's a guy selling them in the UK for about £280. Perhaps someone can provide the link.
 

£2.49

Pedelecer
Jan 3, 2013
31
0
There's a very limited choice of crank-drive kits. The cheapest and easiest to fit, whilst having sufficient power for what you want is the GNG Gen1.
mid 450W (brushless)
There's a guy selling them in the UK for about £280. Perhaps someone can provide the link.
That sounds very interesting at a pretty good price!
 
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Deleted member 4366

Guest
Yes, but better with 36v. You can get one of those 20aH 36v Shrinktube batteries from BMBBattery for about £250. 48v will spin the crank too fast - it's fast enough at 36v. Also, 36v gives a bit less power, which is better for belt life. It'll still be enough for what you want. Even at 36v, it's got noticeably more power than a Bosch motor. The standard controller's 22 amps, so that's about 1000w from the battery.
 

£2.49

Pedelecer
Jan 3, 2013
31
0
Yes, but better with 36v. You can get one of those 20aH 36v Shrinktube batteries from BMBBattery for about £250. 48v will spin the crank too fast - it's fast enough at 36v. Also, 36v gives a bit less power, which is better for belt life. It'll still be enough for what you want. Even at 36v, it's got noticeably more power than a Bosch motor. The standard controller's 22 amps, so that's about 1000w from the battery.
So would this be the one for me ?
New product 36V 250W electric bike kit crank drive mid mount can change gears
 
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Deleted member 4366

Guest
No. That one won't be powerful enough. The price direct from GNG is about £270. There was a guy on Ebay selling them from the UK at about the same price. I think this is the seller, so you could e-mail him. New 36V 36 volt 250W electric bike kit crank drive mid mount can change gears | eBay
You should contact that guy in your link and ask him if he's got a 36v 450w brushless one without battery.
It was very quick to get it direct from GNG - about a week - so if you can't get one from the UK, go direct.
 

£2.49

Pedelecer
Jan 3, 2013
31
0
No. That one won't be powerful enough. The price direct from GNG is about £270. There was a guy on Ebay selling them from the UK at about the same price. I think this is the seller, so you could e-mail him. New 36V 36 volt 250W electric bike kit crank drive mid mount can change gears | eBay
You should contact that guy in your link and ask him if he's got a 36v 450w brushless one without battery.
It was very quick to get it direct from GNG - about a week - so if you can't get one from the UK, go direct.
I've just sent him a email. Really appreciate your help.
 
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£2.49

Pedelecer
Jan 3, 2013
31
0
That was quick he's just got back to me and says Yes we do sell 450w brushless motor kit and its 48v not 36v but can be used with 36v battery if you have a 36v controller. Kits will be available from monday.
Would this be any good ?
 

Old_Dave

Esteemed Pedelecer
Sep 15, 2012
1,211
2
Dumfries & Galloway
Beware of the crank size, it may be smaller than the one you have... So it may mean having to fit a smaller freewheel to be able to peddle fast enough


Sent from my iPhone using Tapatalk
 
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Deleted member 4366

Guest
That was quick he's just got back to me and says Yes we do sell 450w brushless motor kit and its 48v not 36v but can be used with 36v battery if you have a 36v controller. Kits will be available from monday.
Would this be any good ?
If you've got to get a controller from somewhere, you might just as well get the whole kit from GNG. Alternatively, you could get his kit and pay the extra £12 for a KU93 controller from BMSBattery if you get the battery from there. The GNG motor can be quite power hungry because maximum power is always on tap by changing gear. It takes a lot of discipline to be gentle on the throttle. It's really good fun, free-wheeling down a steep hill at over 30mph, and then giving it full throttle in top gear for about 800w additional power. You therefore need a 20aH battery.
 

£2.49

Pedelecer
Jan 3, 2013
31
0
It takes a lot of discipline to be gentle on the throttle. It's really good fun, free-wheeling down a steep hill at over 30mph, and then giving it full throttle in top gear for about 800w additional power. You therefore need a 20aH battery.
Me doing 30mph with my brakes and all that weight, It would be like something out of Runaway Train :eek:
Still upsetting Taxi Drivers down here might be fun! :D

Taxi drivers lose fight against 20mph speed limit as Brighton becomes latest city to introduce restrictions - Home News - UK - The Independent
 
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Deleted member 4366

Guest
With this one, you control your speed with the gears rather than the throttle. You'll see what I mean if you get one.
 

jackhandy

Esteemed Pedelecer
May 20, 2012
1,820
323
the Cornish Alps
In your situation, with crappy brakes & up to 75kg plus you & a hefty bike all shoving, I'd feel inclined to investigate the practicality of fitting a drogue.
 

£2.49

Pedelecer
Jan 3, 2013
31
0
Joking apart I am drawn back to my original plan of using the Sunstar ibike S03 system. I just think it would allow me to ride my bike at more controllable speeds but give me the push I need to tackle the steep hills, and I'm not sure if I want a throttle on my bike as I still want it to feel very much like a push bike.