woahdae
1 mW
I’ve been researching ebikes for a long time, and have been unable to pull the trigger on a new build so far. I did get a basic 250w front hub kit for my current bike, but that was always a stopgap. I would love a sanity check on my current direction, maybe it’d give be the confidence to drop the cash!
What I’ve landed on so far is a sport touring frame with a Falco (direct drive) 500w rear hub motor for a clean PAS experience, plus a geared 250w front hub motor like this one on a simple throttle for extra torque.
The requirements:
* #1, pull myself (~180lbs) and potentially 50lbs of stuff (kid, commuting junk, etc) up a mile long 7-9% grade at 15mph with a mild contribution on my part.
* 20mph cutoff is OK, don’t need/want to go much over 25 anyways.
* Lightweight, entire bike must be <55lbs to legally go on bus rack. It’s OK to remove the battery for this, but nice if I don’t have to.
Nice to have
* Street legal, i.e. 20mph & 750w. This is because I already want a light, torquey system that seems achievable with 750w, so why not. I’m always advocating ebikes among friends, co-commuters, etc, and if I’m not street legal I’ll get called out on it.
* Clean installation, minimal wiring. I don’t even need a display, necessarily.
* Regen for the long, rainy descent down said 7-9% mile-long hill to check my speed while carrying the kiddo without wearing on the brakes.
* Regen for charging ebike lights to provide a means to get home in the dark if my battery is dead.
Non factors
* Range. More is better, all things equal, but not a deciding factor.
* Top speed. I’m happy at 20mph, maybe 25. Actually once up to speed on a flat, the effort to stay at speed is the right amount of exercise for me.
* Cost. I don’t have a car, so in other words the money I would spend on insurance and depreciation can go to a bike!
So, torque is mostly what I need, and both the 500w and 750w falco motors claim 60nm of torque, which seems like just barely enough. The new Bafang 250w motors claim 42nm of torque, and only weigh just over 3lbs, so adding that gives 102nm total torque for a nominal weight increase.
I think I could get the 500w Falco system, and perhaps this controller and these cables and splice the 250w motor into the battery? Is it that easy?
So...
Does this make sense as per my requirements? Is there a better way to do the wiring? Also, 36v or 48v? Seems like 36v is the path of least resistance because the small front motors are 36v. I’d only care if it affected my ability to haul cargo at 10-15mph up 7-15% grades (usually max 9%). I’ve read lots of pages about max torque vs peak power, voltage, and such, but I’m going a little cross eyed now and can’t make sense of how it would affect my trip up a hill at relatively low speeds.
Thanks for any feedback. This forum has been extremely helpful so far, and apologies if something is obvious but I think I’m saturated at this point. Hopefully some advice can get me over the line.
What I’ve landed on so far is a sport touring frame with a Falco (direct drive) 500w rear hub motor for a clean PAS experience, plus a geared 250w front hub motor like this one on a simple throttle for extra torque.
The requirements:
* #1, pull myself (~180lbs) and potentially 50lbs of stuff (kid, commuting junk, etc) up a mile long 7-9% grade at 15mph with a mild contribution on my part.
* 20mph cutoff is OK, don’t need/want to go much over 25 anyways.
* Lightweight, entire bike must be <55lbs to legally go on bus rack. It’s OK to remove the battery for this, but nice if I don’t have to.
Nice to have
* Street legal, i.e. 20mph & 750w. This is because I already want a light, torquey system that seems achievable with 750w, so why not. I’m always advocating ebikes among friends, co-commuters, etc, and if I’m not street legal I’ll get called out on it.
* Clean installation, minimal wiring. I don’t even need a display, necessarily.
* Regen for the long, rainy descent down said 7-9% mile-long hill to check my speed while carrying the kiddo without wearing on the brakes.
* Regen for charging ebike lights to provide a means to get home in the dark if my battery is dead.
Non factors
* Range. More is better, all things equal, but not a deciding factor.
* Top speed. I’m happy at 20mph, maybe 25. Actually once up to speed on a flat, the effort to stay at speed is the right amount of exercise for me.
* Cost. I don’t have a car, so in other words the money I would spend on insurance and depreciation can go to a bike!
So, torque is mostly what I need, and both the 500w and 750w falco motors claim 60nm of torque, which seems like just barely enough. The new Bafang 250w motors claim 42nm of torque, and only weigh just over 3lbs, so adding that gives 102nm total torque for a nominal weight increase.
I think I could get the 500w Falco system, and perhaps this controller and these cables and splice the 250w motor into the battery? Is it that easy?
So...
Does this make sense as per my requirements? Is there a better way to do the wiring? Also, 36v or 48v? Seems like 36v is the path of least resistance because the small front motors are 36v. I’d only care if it affected my ability to haul cargo at 10-15mph up 7-15% grades (usually max 9%). I’ve read lots of pages about max torque vs peak power, voltage, and such, but I’m going a little cross eyed now and can’t make sense of how it would affect my trip up a hill at relatively low speeds.
Thanks for any feedback. This forum has been extremely helpful so far, and apologies if something is obvious but I think I’m saturated at this point. Hopefully some advice can get me over the line.