Rear hub and mid drive motor working at the same time. what is the the outcome?

What do think about this mid drive system?
My bet is, when you are all done messing with a setup like this, you could have purchased a mid drive capable of doing what you want to do - with warranty.
 
Lighteningrod <——- click



What do think about this mid drive system?

noisy and high maintenance.
 
This bike needs more power as I am not able to climb steep hills or steep dirt roads. Also I would like to pull a bike trailer like the Burley flat bed. I am not in it to go fast or to tearing down public roads but more torque. More off road capability.
Gordian9. To get more climbing power/torque you should change out your rear cassette. If you change to an 11-42T+ or or 11-46T cassette, this will make it considerably easier to climb because your pedaling will become more efficient, and your motor assist more effective. It will not change the output of your motor, just make your human input more effective. Looks like you may have a 12-32T rear cassette, I cannot tell. If you change your cassette to 42T+ you will probably need to change out your derailleur, or at least get a derailleur hanger extension. You can further increase your climbing power by additionally changing your front chainring to a ring with less teeth. I installed a 30T chainring coupled with an 11-42T cassette (1400W/30amp mid-drive motor). My front end started popping wheelies on steep hills, I could hardly keep it on the ground. I ended up ditching the 30T chainring for a 40T. Still pulls wheelies on steep hills, but not as much. Total cost, $100? $150 if you change out the shifter too. BTW, if your motor is a threaded "screw-on" freewheel you won't be able do the above. It will only work if your hub motor is a Shimano type freewheel cassette

That change will give you more climbing power, albeit from muscle exertion, not motor power/torque. If you reduce the teeth in your front chainring you will sacrifice some top end speed on the flats

The next, more expensive, and more complicated way to get more power from your motor (and exhaust your battery quicker) is to change your motor controller to increase your controller amps (25-30-40 amps?) output. I'm taking a wild guest that your controller puts out 17-22 amps. This will probably necessitate that you change your display too. They need to be compatible. I think your motor is a Shengyi or AKM, you can check that. Read up on that and beware that too many amps, under too much of a load can overheat your motor quickly and break it or the controller. You can get configurable controllers that will monitor the heat of the controller and motor and reduce power accordingly. You can get a lot of info on that stuff here: www.ebikes.ca. They are probably the best when it comes to rear hub cargo hauling bike configurations. They don't do, nor believe in mid-drives at all. You should read a lot about this and get advice before you DIY.

Take a look at their front wheel hub motors that you could add. You'd need more battery, and another controller, but their Cycle Analyst display can operate with two motors and two controllers.

If you pump extra amps into your motor(s), you will run your battery down quicker so you will need to upgrade your battery to more than your current 14Ah battery, or carry a secondary battery with you in a backpack, rear/front rack, or cargo wagon. I run with two 20Ah batteries on my mid-drive and I never run out of juice.

Don't go for "cheap" on the controller/display configuration. The Grin Technologies stuff will cost you $500-$575? to add a controller and display. A battery from Walkie is $430. So figure an easy $1,000, after you change out your transmission.

You might ask, what about changing the motor? There are rear motors with more torque, but they will need more power/amps too so you would need a new controller, display, and extra battery. I would just start with upgrading your controller first.

Lastly, if you intend to climb hills and tow a trailer, and this current bike does not work for you, I recommend that you take your first loss now. Sell your current ride and get a mid-drive bike with considerably more power after doing a good amount of research.

My Dad used to always tell me "your first loss, is your best loss".
 
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I put a 2000w hub on the front along with a 2000w rear hub motor..tons of fun 👍👍


Who weights more: you or the ebike😉 ? i'm guessing 135 pounds for the ebike...

Can u share some info about the 2 controllers you used and wht AH battery ? 220mm rotors ?
 
Who weights more: you or the ebike😉 ? i'm guessing 135 pounds for the ebike...
Can u share some info about the 2 controllers you used and wht AH battery ? 220mm rotors ?
203mm F/R

Not going to lie, it's a heavy bugger but still scoots to ~40mph

My rear motor battery is a 72v 20AH & front is 48v 20AH

The rear is controlled with a left hand thumb throttle/sabovoton controller & front controlled by a 48v twist throttle controller

Added lighting, horn and F/R turn signals and was able to use it as a work commuter all last summer. Use motorcycle helmet and jacket while commuting. Looking forward to riding it to work again as soon as it warms up a little more.

Some additional pics (203s not pictured)
 

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Would an electric trail bike be the best answer? If you are trying to build a better mousetrap, good luck. I love electric, nowadays I have been giving some thought to an ICE powered thingy burning a low emission fuel( alcohol) Perhaps a Hybrid has some merit with a small Genset and reasonable battery size.If you really want electric power look at some of the trial bikes, pulling 100# up a grade on a trailer is starting to encroach on real vehicle territory. Of course do as you wish, I tossed the middrive rear hub combo around as a mental exercise I think the disadvantages out weigh the merits.
Just for an instant start thinking about Tadpole trikes, I came into this world as innocent and idealistic as could be, reality soon reared its ugly head, these light machines are not very safe at speed, I believe you said 40 mph?( somebody did) take a deep breath and think, you hit a large deer or run off the trail at 40 mph, you had better have good cell coverage.
Just a thought, the "Wiz's" and "Mage's" hereabouts are truly worth a listen.
Remember one thing, this tech and art gets better all the time. eventually you will be able to buy a turnkey device that checks most of your boxes and the advice about the "cargo" style ebike maynot be as farfetched as one may think.
 
This bike needs more power as I am not able to climb steep hills or steep dirt roads. Also I would like to pull a bike trailer like the Burley flat bed. I am not in it to go fast or to tearing down public roads but more torque. More off road capability.

The problem right off the bat is you have a hub motor and hub motors are great for flat bottom riding, going to the grocery story and tooling around town; not climbing hills like you want to do. Wrong bike for the wrong application, sorry. Climb hills long enough with the hub motor and you will be cooking the internals inside that hub in short order until it's done for.

What is required to do what you want to do in a consistently reliable manner is either a purpose built factory Mid Drive emtb, be it 27.5 or 29 inch tired emtb or a 26 inch fat tired emtb, mid drive. Those bikes would be sold under the brands like Quiet Kat, Trek, Specialized, Giant, Yamaha, Haibike or a dozen plus other higher end brands. They do come at a cost. There are also lightly used ones at a lower cost at your usual Craigslist or Falsebook Marketplace. Like going off roading in your 4x4: the further back or further up you want to go on that trail means more dollars are spent getting to that destination.

Or you could go the home made route using a mid drive Bafang attached to a premium, used MTB from the above noted brands Trek, Giant, or Specialized. Think Pie Plate sized rear cassettes with that super low gearing to climb them hills, attached to an appropriately sized front chain ring made specifically for mountain e-biking.

Look up what member @K PierreR has done with his fatbike and that is exactly what you need to go climbing hills, pulling trailers with.
 
Would an electric trail bike be the best answer? If you are trying to build a better mousetrap, good luck. I love electric, nowadays I have been giving some thought to an ICE powered thingy burning a low emission fuel( alcohol) Perhaps a Hybrid has some merit with a small Genset and reasonable battery size.If you really want electric power look at some of the trial bikes, pulling 100# up a grade on a trailer is starting to encroach on real vehicle territory. Of course do as you wish, I tossed the middrive rear hub combo around as a mental exercise I think the disadvantages out weigh the merits.
Just for an instant start thinking about Tadpole trikes, I came into this world as innocent and idealistic as could be, reality soon reared its ugly head, these light machines are not very safe at speed, I believe you said 40 mph?( somebody did) take a deep breath and think, you hit a large deer or run off the trail at 40 mph, you had better have good cell coverage.
Just a thought, the "Wiz's" and "Mage's" hereabouts are truly worth a listen.
Remember one thing, this tech and art gets better all the time. eventually you will be able to buy a turnkey device that checks most of your boxes and the advice about the "cargo" style ebike maynot be as farfetched as one may think.
My thought is there are already endless options available. Check out the number of people shopping for their first bike for months! I don't see that changing any time soon. We're going to have electric solutions to fill every niche.
 
The problem right off the bat is you have a hub motor and hub motors are great for flat bottom riding, going to the grocery story and tooling around town; not climbing hills like you want to do. Wrong bike for the wrong application, sorry. Climb hills long enough with the hub motor and you will be cooking the internals inside that hub in short order until it's done for.

What is required to do what you want to do in a consistently reliable manner is either a purpose built factory Mid Drive emtb, be it 27.5 or 29 inch tired emtb or a 26 inch fat tired emtb, mid drive. Those bikes would be sold under the brands like Quiet Kat, Trek, Specialized, Giant, Yamaha, Haibike or a dozen plus other higher end brands. They do come at a cost. There are also lightly used ones at a lower cost at your usual Craigslist or Falsebook Marketplace. Like going off roading in your 4x4: the further back or further up you want to go on that trail means more dollars are spent getting to that destination.

Or you could go the home made route using a mid drive Bafang attached to a premium, used MTB from the above noted brands Trek, Giant, or Specialized. Think Pie Plate sized rear cassettes with that super low gearing to climb them hills, attached to an appropriately sized front chain ring made specifically for mountain e-biking.

Look up what member @K PierreR has done with his fatbike and that is exactly what you need to go climbing hills, pulling trailers with.
My thinking is that if I have both systems. A rear hub motor and mid drive with only throttle option. I would start with peddle assist with the hub motor then when I start struggle on a steep climb, I would kick on the mid drive for that extra power. Any thoughts?
 
My thinking is that if I have both systems. A rear hub motor and mid drive with only throttle option. I would start with peddle assist with the hub motor then when I start struggle on a steep climb, I would kick on the mid drive for that extra power. Any thoughts?
Too much complication, too much weight, too much cost maintaining and feeding two separate systems. There is a reason why manufacturers haven't come out with a similar set up, no?

In regards to these steep climbs you have in mind; you have yet to articulate where exactly you want to ride. It's quite possible somebody here on an e-mtb have done it or completed something very similar to conditions you want to ride in. So let us know. This is a very willing and helpful crowd who wants to share their own real-life experiences.

Even a high powered enduro gas engine motorcycle has it's limits as to how steep it can climb before gearing, tires, horsepower and traction let go. A lighter weight e-mtb has it's own restrictive limits before that rear tire runs out of traction.
 
I think @m@Robertson runs this dual setup for a fat bike fast commuter bike and likes the setup. He claims its very hard to get the integration set up properly and requires a thoughrough understanding of best use pattern. Without a thoughrough understanding your range would likely be limited and your maintenance high. The setup is a tinkerers dream and expensive. Not what I would build for long distance off grid travel due to handling and weight carrying capacity.
 
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