Anybody else go from a rear hub motor to mid drive?

teskow

Member
I guess there is a time and a place where certain drive systems shine over others. I suppose if one rides a bike like one would race an automobile a mid-engine is better balanced but that isn't an issue to me. I don't race anything anymore, especially my bicycle. Systems seem to be a matter of opinion and or maybe it is just what one owns at the time. Some electric autos are direct drive others have transmissions. I happen to ride a Juiced RC with a 750 W hub motor. It sports cadence, torque sensing, a hand throttle, multiple PAS settings plus 9 gears. I can ride very slowly as I do so alongside of walkers. I use the torque system so I can move the pedals without power being fed the motor all I want without the power kicking in as long as not much peddle pressure is inputed. If little pressure is inputed no assistance will come on. A little more though and it kicks in very gently sometimes not even feeling it but I can see it on the watts being fed the motor. It starts on the torque setting at 35W all the way up 500 plus as one pedals very hard. Very much like an auto accelerator, gas pedal.
The machine is fast off the line in any gear especially when also using the throttle. I haven't encountered a hill I can't climb with ease. If I break something in my chaining system my throttle will get me home.
Of course like any rider we always dream of something better but I just can't think of anything that would serve me better so am sticking with what I have.
No I do not work for Juiced Bikes.
 

AHicks

Well-Known Member
That's me, dreaming of something better. I likely own one of the ultimate hub drives, the MAC 12t (1000+ watts). Many will tell you it's about the most torque you can buy in a hub. That's coupled with an aftermarket 35a KT controller, which over the last couple of years is dialed in about perfectly. Lest you think this bike must use a gob of power, I can figure on about a 35 mile range safely.

I LOVE this bike, but looking forward to a fatty. This 70 year old butt is getting tender, and the fatty's are supposed to be the ultimate when it comes to ride. The fact I'm used to the the power this bike has, and would not want to take a step backward, led me directly to the Ultra motor...
 

legsofbeer

Active Member
That's me, dreaming of something better. I likely own one of the ultimate hub drives, the MAC 12t (1000+ watts). Many will tell you it's about the most torque you can buy in a hub.

I'm looking forward to hearing how this goes. I decided against replacing the geared hub with a lower torque direct drive that would give more top speed at the expense of acceleration, because of all the stops in my urban commuting.
 

Stefan Mikes

Well-Known Member
Whereas the Turbo Vado class 3 does not like it. It’s has more torque and although it’s possible to do stops and starts it’s just not much fun. The best description is like trying to drive a Corvette sports car in stop and go rush hour, not much fun.
@Marci jo, that's because of reasons known to you and me -- you cannot tune your Vado. Okay, you own the "Corvette" and like fast riding! :)
 

Kayakguy

Member
I have had the juiced bikes fat tire Ripcurrent S with bafang 750w rear hub motor for 1.5 yrs and now I decided I wanted a mid drive so I got the Biktrix ultra eagle with bafang mid drive ultra motor (1500w Peak).

Has anybody else came here from a rear hub bike and switch to a mid drive? I feel like it's going to take me a bit to get used to. The main thing is how the motor drops rpms and you feel that slight pause when you change gears. It's kind of annnoying but I am just now learning this is a safety feature for mid drives. With my rear hub motor there's no kind of delay or pause or nothing between changing gears. I can go from a stop and speed up quickly and "click, click, click" all the way up to 9th gear right away.

With the mid drive when I want to take off fast from a stop and I want to change gears in the same way Im used to with the rip current it's like "click" "pause" "click" "pause". So it's annoying when you want to pedal hard and speed up quickly and then you get these pauses even though when the torque kicks in I am going way freaking faster on the ultra eagle than my Ripcurrent but it's just kind of weird I guess it doesn't feel "natural". The torque is pretty crazy but I just seem to get annoyed with the pause between changing gears because I'm used to changing fast.

Also with the rear hub if I was approaching a steep hill (lots of hills in Colorado) and forgot to get into low gear until the last second it didn't matter I can quickly change into the lowest gear right away and go up the hill just fine. However with the mid drive you have to change gears way before otherwise if you forget and try to change into the lowest gear at the last second while you're on the hill you will get stuck because the motor pauses between gear changes and you lose all assist and now you're trying to support this heavy bike midway on the hill. My entire power actually shut off on me at that moment when that happened.

I don't want to give up on it (the midrive cost me $4k) like I said maybe I just need to get used to it or find a different style of changing gears for the mid drive. I do notice during a gear change on the mid drive after the pause it picks up way more speed/torque all of a sudden which is pretty fun feeling. It doesn't really feel "natural" though like it does on the rear hub it feels more natural to me like riding a bike but with just a lot of assist with the mid drive you definately know it's the motor when it kicks in all of a sudden I guess the power doesn't feel as smooth from slow to fast because of the pauses.

I just got it a few days ago so like I said getting used to it but another thing I noticed again not sure if it's just in my head but I feel like when I stop pedaling on the mid drive it's like my speed starts dropping much more quicker than on the rear hub which feels like when I stop pedaling I can keep coasting for longer. I don't know if it's because the Ripcurrent is 4" fat tires or maybe it's the 52t chainring? The mid drive is 44t. Not sure if that has anything to do with it. Or just the fact the rear hub being in the rear tire it kind of "pushes" you so you are coasting on momentum? Does that make sense?

Or does it sound like I am just not going to be happy with mid drive? Maybe I can still return it I believe I have 14 days. If there's no real "getting used to it" then maybe I should just think about returning it and getting another rear hub motor? If it sounds like I prefer that type of riding style? I really want to like it it looks awesome I am having fun with it but like I said the pauses between the gears is getting on my nerves.
Maybe if you approach hills as if you were on a non-powered bike. You'd probably get back into the habit of gearing down pretty quickly.
 

Ebiker33

Well-Known Member
Here is what one vendor said about it



Gearshift Sensor

Cuts off motor power momentarily when shifting gears. The motor will shut off for less than 3 milliseconds when shifting gears to protect the drive train. As the motor is quite powerful, this feature is necessary for the smooth shifting of gears.

I don't see how 0.003 second delay could really effect anything.
 

AHicks

Well-Known Member
Here is what one vendor said about it



Gearshift Sensor

Cuts off motor power momentarily when shifting gears. The motor will shut off for less than 3 milliseconds when shifting gears to protect the drive train. As the motor is quite powerful, this feature is necessary for the smooth shifting of gears.

I don't see how 0.003 second delay could really effect anything.

Seems pretty reasonable here as well - but I haven't ridden one just yet. That will be changing soon as the new bike is equipped with one.
 

Thomas Jaszewski

Well-Known Member
I did the beta testing and distributed gear sensor samples to posters on endless_sphere. In my personal opinion, it's an unnecessary add on. Tapping a brake lever cuts the motor for clean shifting. The GS is a bit quicker and is very popular with kit builders. I have a few left if anyone wants to mess with one.
 

Delta

Member
I have an Addmotor P7 550 rear hub (750W) and a m2s Ultra Fat mid drive. I got the rear hub bike first and the mid drive about seven months later in Sept. of 2018. Both bikes have the gear shift motor cut-off switch and throttles. I like the rear hub bike much better than the mid drive. The rear hub bike is much peppier and just feels like it is more fun to drive. In the two years I have had the bikes I still find the mid drive the lesser bike. Both bikes have 4 inch fat tires. Also, the torque sensor went out on the mid drive last month and as of this writing is not available as a replacement part, so that particular motor is useless.
 

AHicks

Well-Known Member
Short trail ride on the new bike with the built in shift sensor (stock on Bafang Ultra) and to me it's a barely noticeable non event. I suppose that impression could change, but it's not a place I'm going to be looking for trouble right away...
 

AHicks

Well-Known Member
HOLY COW....
Transitioning from a really powerful hub drive w/very nicely done cadence sensing, to an even more powerful mid drive with both torque and cadence sensing combined (and questionable programming!), I find I'm learning how to ride the new e-bike a whole different ball game. Though I'd like to start making changes regarding differences in the controller programming, I'm going to try to avoid knee jerk (over) reactions by riding the bike for a bit as it was delivered - while trying to maintain an open mind - as much as possible anyway.

Regarding that shift sensor delay, I managed to nearly completely stall the bike on a second ride while shifting from 3rd to 2nd a little late. The bike fell flat on it's face with a pause in power way way beyond 0.003 of a second. By time the power came back on the bike had nearly stopped. This vs. pauses that you don't even notice or notice just slightly. The difference? I'm going to say it's cadence speed. At very low cadence, my bet right now is you can plan on a pregnant pauses with a low cadence/late shift scenario. Tune-able issue? Dunno.

The other thing I've run into is false starts (bike lurches ahead) while climbing aboard in PAS 1. I have absolutely no idea how or what I'm doing to cause this. I've been caught completely by surprise each time it's happened. I do know for sure I am NOT touching the throttle. It's happened 3 times now, in the first 10 miles. My cadence based hub drive bike, which is set to turn the power on almost immediately as the crank is turned, has had maybe 3 false starts since I started riding it 3 years ago. I can deal with that kind of frequency. So that's an issue that's got my attention. Fat tires, heavy bike, gob's of power, likely not quite having your balance = unpleasant experience. I KNOW there's a setup function that will fix this issue. That's a mod that will likely happen soon - but I'd like to know for sure that the crank movement is the source of my evil first.

Not trying to sound like I'm complaining. This is a really nice bike - I just need to get used to it! -Al
 

Ebiker33

Well-Known Member
HOLY COW....
Transitioning from a really powerful hub drive w/very nicely done cadence sensing, to an even more powerful mid drive with both torque and cadence sensing combined (and questionable programming!), I find I'm learning how to ride the new e-bike a whole different ball game. Though I'd like to start making changes regarding differences in the controller programming, I'm going to try to avoid knee jerk (over) reactions by riding the bike for a bit as it was delivered - while trying to maintain an open mind - as much as possible anyway.

Regarding that shift sensor delay, I managed to nearly completely stall the bike on a second ride while shifting from 3rd to 2nd a little late. The bike fell flat on it's face with a pause in power way way beyond 0.003 of a second. By time the power came back on the bike had nearly stopped. This vs. pauses that you don't even notice or notice just slightly. The difference? I'm going to say it's cadence speed. At very low cadence, my bet right now is you can plan on a pregnant pauses with a low cadence/late shift scenario. Tune-able issue? Dunno.

The other thing I've run into is false starts (bike lurches ahead) while climbing aboard in PAS 1. I have absolutely no idea how or what I'm doing to cause this. I've been caught completely by surprise each time it's happened. I do know for sure I am NOT touching the throttle. It's happened 3 times now, in the first 10 miles. My cadence based hub drive bike, which is set to turn the power on almost immediately as the crank is turned, has had maybe 3 false starts since I started riding it 3 years ago. I can deal with that kind of frequency. So that's an issue that's got my attention. Fat tires, heavy bike, gob's of power, likely not quite having your balance = unpleasant experience. I KNOW there's a setup function that will fix this issue. That's a mod that will likely happen soon - but I'd like to know for sure that the crank movement is the source of my evil first.

Not trying to sound like I'm complaining. This is a really nice bike - I just need to get used to it! -Al

You should talk to Roshan/Biktrix, that doesn't sound like a normal delay time.
 

ElevenAD

Well-Known Member
HOLY COW....
Transitioning from a really powerful hub drive w/very nicely done cadence sensing, to an even more powerful mid drive with both torque and cadence sensing combined (and questionable programming!), I find I'm learning how to ride the new e-bike a whole different ball game. Though I'd like to start making changes regarding differences in the controller programming, I'm going to try to avoid knee jerk (over) reactions by riding the bike for a bit as it was delivered - while trying to maintain an open mind - as much as possible anyway.

Regarding that shift sensor delay, I managed to nearly completely stall the bike on a second ride while shifting from 3rd to 2nd a little late. The bike fell flat on it's face with a pause in power way way beyond 0.003 of a second. By time the power came back on the bike had nearly stopped. This vs. pauses that you don't even notice or notice just slightly. The difference? I'm going to say it's cadence speed. At very low cadence, my bet right now is you can plan on a pregnant pauses with a low cadence/late shift scenario. Tune-able issue? Dunno.

The other thing I've run into is false starts (bike lurches ahead) while climbing aboard in PAS 1. I have absolutely no idea how or what I'm doing to cause this. I've been caught completely by surprise each time it's happened. I do know for sure I am NOT touching the throttle. It's happened 3 times now, in the first 10 miles. My cadence based hub drive bike, which is set to turn the power on almost immediately as the crank is turned, has had maybe 3 false starts since I started riding it 3 years ago. I can deal with that kind of frequency. So that's an issue that's got my attention. Fat tires, heavy bike, gob's of power, likely not quite having your balance = unpleasant experience. I KNOW there's a setup function that will fix this issue. That's a mod that will likely happen soon - but I'd like to know for sure that the crank movement is the source of my evil first.

Not trying to sound like I'm complaining. This is a really nice bike - I just need to get used to it! -Al
never hop on a bike with a torque sensor without grabbing the brake first or make sure you dont touch the pedals when hopping on, any pedal pressure can and will cause the bike to go!
 
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AHicks

Well-Known Member
i have the same bike as AHicks and i barely notice the sensor, its very fast,only stalls my bike long enough to shift?
That was my first impression. See post # 31. That changed when I found a situation where it's not so quick, as described above. This was on a trail at a fairly low speed. I rounded a corner and seeing a hill right there I went from 3rd to 2nd at maybe 5mph while climbing. A late shift, pure and simple.

Try it. Slow way down in PAS1 to a speed you might be running on a tight single track trail, or maybe even while climbing. Point the bike at a hill so there will be no momentum to carry you through the shift, and see what happens....
 
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AHicks

Well-Known Member
never hop on a bike with a torque sensor without grabbing the brake first or make sure you dont touch the pedals when hopping on, any pedal pressure can and will cause the bike to go!

I'm thinking there's a very good chance that's exactly what's happening, me putting pressure on a pedal, but that pedal is SUPPOSED to move through so much travel BEFORE the power is applied. If I am actually touching that pedal to cause this, that pedal should have to move a couple of inches, far enough for a magnet to pass the sensor at least, prior to anything happening. That's no different than a cadence based system.

The torque sensor will sense the weight of my foot no doubt, but that event alone should NOT power up the bike while at a stand still. Not if I'm reading/understanding the configuration parameters correctly anyway.

STILL, I was thinking the same thing. For right now at least, I WILL be making sure I have a handful of brake while mounting. Not something I've been doing prior to this bike, its going to be be part of the learning curve. -Al
 
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D

Deleted member 4210

Guest
I have had the juiced bikes fat tire Ripcurrent S with bafang 750w rear hub motor for 1.5 yrs and now I decided I wanted a mid drive so I got the Biktrix ultra eagle with bafang mid drive ultra motor (1500w Peak).

Has anybody else came here from a rear hub bike and switch to a mid drive? I feel like it's going to take me a bit to get used to. The main thing is how the motor drops rpms and you feel that slight pause when you change gears. It's kind of annnoying but I am just now learning this is a safety feature for mid drives. With my rear hub motor there's no kind of delay or pause or nothing between changing gears. I can go from a stop and speed up quickly and "click, click, click" all the way up to 9th gear right away.

With the mid drive when I want to take off fast from a stop and I want to change gears in the same way Im used to with the rip current it's like "click" "pause" "click" "pause". So it's annoying when you want to pedal hard and speed up quickly and then you get these pauses even though when the torque kicks in I am going way freaking faster on the ultra eagle than my Ripcurrent but it's just kind of weird I guess it doesn't feel "natural". The torque is pretty crazy but I just seem to get annoyed with the pause between changing gears because I'm used to changing fast.

Also with the rear hub if I was approaching a steep hill (lots of hills in Colorado) and forgot to get into low gear until the last second it didn't matter I can quickly change into the lowest gear right away and go up the hill just fine. However with the mid drive you have to change gears way before otherwise if you forget and try to change into the lowest gear at the last second while you're on the hill you will get stuck because the motor pauses between gear changes and you lose all assist and now you're trying to support this heavy bike midway on the hill. My entire power actually shut off on me at that moment when that happened.

I don't want to give up on it (the midrive cost me $4k) like I said maybe I just need to get used to it or find a different style of changing gears for the mid drive. I do notice during a gear change on the mid drive after the pause it picks up way more speed/torque all of a sudden which is pretty fun feeling. It doesn't really feel "natural" though like it does on the rear hub it feels more natural to me like riding a bike but with just a lot of assist with the mid drive you definately know it's the motor when it kicks in all of a sudden I guess the power doesn't feel as smooth from slow to fast because of the pauses.

I just got it a few days ago so like I said getting used to it but another thing I noticed again not sure if it's just in my head but I feel like when I stop pedaling on the mid drive it's like my speed starts dropping much more quicker than on the rear hub which feels like when I stop pedaling I can keep coasting for longer. I don't know if it's because the Ripcurrent is 4" fat tires or maybe it's the 52t chainring? The mid drive is 44t. Not sure if that has anything to do with it. Or just the fact the rear hub being in the rear tire it kind of "pushes" you so you are coasting on momentum? Does that make sense?

Or does it sound like I am just not going to be happy with mid drive? Maybe I can still return it I believe I have 14 days. If there's no real "getting used to it" then maybe I should just think about returning it and getting another rear hub motor? If it sounds like I prefer that type of riding style? I really want to like it it looks awesome I am having fun with it but like I said the pauses between the gears is getting on my nerves.
That's not a typical mid drive on the Biktrix. You won't feel any pausing or dropping of RPM's with a real mid drive motor, like those made by Yamaha, Bosch, Brose, or Shimano. Entirely different and better sensing mechanisms along with very refined internal gearing. Bafang isn't building anything even remotely close to what these premier mid drive manufacturers are building.
 

ElevenAD

Well-Known Member
I'm thinking there's a very good chance that's exactly what's happening, me putting pressure on a pedal, but that pedal is SUPPOSED to move through so much travel BEFORE the power is applied. If I am actually touching that pedal to cause this, that pedal should have to move a couple of inches, far enough for a magnet to pass the sensor at least, prior to anything happening. That's no different than a cadence based system.

The torque sensor will sense the weight of my foot no doubt, but that event alone should NOT power up the bike while at a stand still. Not if I'm reading/understanding the configuration parameters correctly anyway.

STILL, I was thinking the same thing. For right now at least, I WILL be making sure I have a handful of brake while mounting. Not something I've been doing prior to this bike, its going to be be part of the learning curve. -Al
some torque sensors are sensitive and jumpy, the torque sensor on my hub motor cruiser is even more touchy,it jumps forward just from the weight of my leg on the pedal,resting my foot on the pedal at a stoplight will often cause the bike to jump forward if i dont keep my hands on the brake lol, my Ultra is a little less sensitive. with a Cadence bike this is not a concern!
 
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AHicks

Well-Known Member
We'll be keeping an eye on it for sure. When we hook up the computer, we'll make a change here to see if there isn't some sort of compromise we can make that won't kill/ham string the desired sensitivity (sounds like we both like a lot). There's a setting under one of the tabs, forget which exactly, where you can specify how many magnets pass the sensor prior to power being available. We'll add 1 to that number, whatever it is, and see if that creates the desired effect. Learning process for sure. Plenty of patience available here for that kind of tuning.... -Al