MalcolmG
1 mW
Hi all,
We've had a Bakfiets long cargo bike for a few years now, and use it for carting some kids around (1 and 3) and the odd bit of grocery shopping. My wife and I are fairly fit and manage well without any e-assistance, but I think we'd use the bike more if it were electric. In a 5km radius of our house everything is relatively flat, but if I go much further things get a bit steeper. I could envisage doing 20-30km trips with the kids if I had e-assistance. I don't like to go too fast on this bike with the kids in it, and as I'm mostly looking for assistance for getting up hills I think a max assisted speed of 20km/h would be ok (but up to 30km/h wouldn't hurt)
So anyway, I'm thinking of adding a front hub motor (rear wheel has a nice 8 speed Nexus hub which I'd like to keep); the front wheel is 20" and although it currently uses roller brakes, there are mounting tabs on the fork for a disk brake so I will be converting.
At present this is what I'm thinking - I'd be interested in any feedback and/or recommendations for alternatives
Motor - Bafang G311 from Grin Technologies - standard speed windings, which will give better torque at low speeds than the high speed wind Grin recommend for a 20" wheel (I'm happy to sacrifice top speed).
Controller - em3ev 25A (anyone used these and have any feedback?)
Battery - I plan to make my own pack - I have access to a decent number of A123 LiFePO4 26650 cells, probably enough to do a 12s4p configuration, so 39.6V nominal and around 396W/hr.
Thumb throttle, CA2.4.
I'd be interested to hear opinions on this - I have very little experience with e-bikes (my wife bought one a couple of weeks ago, but that was the first time I've ridden one), but I am fairly technically proficient (mech engineer that does electrical engineering for a job, and I have a bevy of bikes and have worked on them for years)
We've had a Bakfiets long cargo bike for a few years now, and use it for carting some kids around (1 and 3) and the odd bit of grocery shopping. My wife and I are fairly fit and manage well without any e-assistance, but I think we'd use the bike more if it were electric. In a 5km radius of our house everything is relatively flat, but if I go much further things get a bit steeper. I could envisage doing 20-30km trips with the kids if I had e-assistance. I don't like to go too fast on this bike with the kids in it, and as I'm mostly looking for assistance for getting up hills I think a max assisted speed of 20km/h would be ok (but up to 30km/h wouldn't hurt)
So anyway, I'm thinking of adding a front hub motor (rear wheel has a nice 8 speed Nexus hub which I'd like to keep); the front wheel is 20" and although it currently uses roller brakes, there are mounting tabs on the fork for a disk brake so I will be converting.
At present this is what I'm thinking - I'd be interested in any feedback and/or recommendations for alternatives
Motor - Bafang G311 from Grin Technologies - standard speed windings, which will give better torque at low speeds than the high speed wind Grin recommend for a 20" wheel (I'm happy to sacrifice top speed).
Controller - em3ev 25A (anyone used these and have any feedback?)
Battery - I plan to make my own pack - I have access to a decent number of A123 LiFePO4 26650 cells, probably enough to do a 12s4p configuration, so 39.6V nominal and around 396W/hr.
Thumb throttle, CA2.4.
I'd be interested to hear opinions on this - I have very little experience with e-bikes (my wife bought one a couple of weeks ago, but that was the first time I've ridden one), but I am fairly technically proficient (mech engineer that does electrical engineering for a job, and I have a bevy of bikes and have worked on them for years)