Universal AWD mid/front hub bike

[Aloles]

I am planning to implement a bicycle project with two-wheel drive AWD:
1. I have a 29" MTB and TSDZ2B 48V 500W OSF, 14AH battery and I would like to support it with a front drive, for example AKM-100H 48V350W, I intend to use two of the same controllers, one integrated with TSDZ, the other purchased for AKM)
Both controllers connected to the VLCD5 display
2. The AWD drive will increase stability in the wet and in corners and increase off-road efficiency.
3. Relieving the engines can reduce energy consumption and increase range, especially in undulating and mountainous terrain.
4. Lightened engines wear less and their resistance to failure increases.
5. Operating costs will decrease because the wear of the cassette/freewheel, chain, spokes and rims will decrease.
6. The cost will decrease because the equipment will be more universal. One bike can replace road, mountain, gravel, MTB.
Currently, the prices of good gravel, mountain and MTB bikes are very high due to the technologies used in them.
Currently, I would like to focus on the mid/hub front drive and consider how to connect the battery, motor controllers and tenso sensors. To ensure smooth distribution of power and torque to the front or rear, depending on road conditions and needs.
I need help in this subject.

 

[2Phast2Delirious]

A couple of my ebikes have dual motors/2WD. The largest benefit, in my opinion, is the peak speed increase. My maximum speed is roughly 22 mph with a single motor 48v/350w and 1000w controller (I'm 215lbs).
With dual motors (2000w), I can get up to 35 mph, but 40 mph is achievable with a +750w motor or lighter rider.

AWD = All wheels run simultaneously, 1 controller

 

[nicobie]

I am planning to implement a bicycle project with two-wheel drive AWD:
1. I have a 29" MTB and TSDZ2B 48V 500W OSF, 14AH battery and I would like to support it with a front drive, for example AKM-100H 48V350W, I intend to use two of the same controllers, one integrated with TSDZ, the other purchased for AKM)
Both controllers connected to the VLCD5 display
2. The AWD drive will increase stability in the wet and in corners and increase off-road efficiency.
3. Relieving the engines can reduce energy consumption and increase range, especially in undulating and mountainous terrain.
4. Lightened engines wear less and their resistance to failure increases.
5. Operating costs will decrease because the wear of the cassette/freewheel, chain, spokes and rims will decrease.
6. The cost will decrease because the equipment will be more universal. One bike can replace road, mountain, gravel, MTB.
Currently, the prices of good gravel, mountain and MTB bikes are very high due to the technologies used in them.
Currently, I would like to focus on the mid/hub front drive and consider how to connect the battery, motor controllers and tenso sensors. To ensure smooth distribution of power and torque to the front or rear, depending on road conditions and needs.
I need help in this subject.

I think you are wrong, but let us know how it works out.

 

[Roviil]

Hi Aloles!

Your AWD e-bike project sounds ambitious! Distributing power between front and rear motors will definitely help with traction and efficiency. Have you considered using something like a kw to hp conversion calculator to determine the combined power output? Proper integration of controllers, sensors, and battery will be key for smooth operation. I'd recommend doing thorough research on wiring configurations and programming to optimize torque distribution based on conditions. It's a complex undertaking but could result in a versatile, capable e-bike if executed well!

 

[Aloles]

Hi Aloles!

Your AWD e-bike project sounds ambitious! Distributing power between front and rear motors will definitely help with traction and efficiency. Have you considered using something like a kw to hp conversion calculator to determine the combined power output? Proper integration of controllers, sensors, and battery will be key for smooth operation. I'd recommend doing thorough research on wiring configurations and programming to optimize torque distribution based on conditions. It's a complex undertaking but could result in a versatile, capable e-bike if executed well!

Hi Roviil!
Thank you for your answer and support. As you can see, there is little interest in the project and it is incomprehensible to me. Either I'm thinking wrong, or people don't realize the benefits that the AWD drive offers. Of course it doesn't discourage me and the project will be created. Determining the output power does not matter because thanks to OSF I can protect the motor and battery by specifying the maximum current in the motors. In order not to complicate the design and perform tests that confirm (or not) my assumptions, each engine will retain a sensor, controller and display. The test should demonstrate the behavior of the bicycle in turns, uphill and downhill slopes, on dry and wet sandy and rocky trails, and on uphill and downhill slopes on hard roads. At the same time, the range for central drive and AWD will be measured and compared. This will be the first phase of the project. The next phase is unification, i.e. one strain gauge, one controller, one display or indicator, two engines and a battery. The next phase is to add a planetary gear in the rear hub and replace the chain with a Gates belt. This will create cheap, easy-to-use and reliable equipment that will outclass very expensive "branded" toys.

 

[Aloles]

A couple of my ebikes have dual motors/2WD. The largest benefit, in my opinion, is the peak speed increase. My maximum speed is roughly 22 mph with a single motor 48v/350w and 1000w controller (I'm 215lbs).
With dual motors (2000w), I can go up to 35 mph, but 40 mph is achievable with a lighter rider.

AWD = All wheels run simultaneously, 1 controller

Hi 2Phast2Delirious!
Thank you for your answer, I'm glad you had a positive experience with AWD. 2xHUB AWD designs are very strong and quite popular. However, most often they are based on a cadence sensor and do not provide the feeling of cycling. Additionally, they often have a throttle to maintain speed. My project is to make a bicycle for people who are not athletes. They often have age, health and fitness limitations and want to safely explore tourist trails in the mountains or ride on roads with many uphill sections, also in cities. This is what electric bikes are for and that's why their popularity is growing. In my project, the mid drive + hub is an evolution of this equipment and its task is to maintain the pleasure of riding but reduce the wear of the bicycle's structural elements and the drive, reduce service costs, increase efficiency in the field and stability on the road. Just like in AWD cars.

 

[99t4]

its task is to maintain the pleasure of riding but reduce the wear of the bicycle's structural elements and the drive, reduce service costs, increase efficiency in the field and stability on the road. Just like in AWD cars.

Those claims are open to debate. I have owned AWD cars. NO WAY does AWD reduce service costs. In fact, AWD increases service costs by far because of the more complex drivetrain. Also, AWD is much less efficient (many more moving parts, extra weight, etc.). Stability on the road? Maybe in certain circumstances like snow, mud, sand, etc., otherwise no. Looks like it is easy to become swayed by attractive marketing hype.

OTOH, don't let my argument against your claims dissuade you from continuing with your project. Hoping you contribute a welcome paradigm shift in the world of ebike technology progress!

 

[scianiac]

One thing you should keep in mind though is the power balance between the two motors, on my 2WD bike I can easily spin the front wheel in low/mid traction conditions because the front will always have less traction than the rear (unless you're going down a real steep hill or the conditions under each tire are different). When this happens the bike becomes very unstable similar to locking up the front brake. This is only a problem if the front motor has more power than traction available. So low traction and/or high power. Since I have matching front and rear hub motors I solved it by just enabling the traction control function on the VESCs driving. With the small front motor you are planning it probably won't be an issue but is something to think about.

 

[Aloles]

Those claims are open to debate. I have owned AWD cars. NO WAY does AWD reduce service costs. In fact, AWD increases service costs by far because of the more complex drivetrain. Also, AWD is much less efficient (many more moving parts, extra weight, etc.). Stability on the road? Maybe in certain circumstances like snow, mud, sand, etc., otherwise no. Looks like it is easy to become swayed by attractive marketing hype.

OTOH, don't let my argument against your claims dissuade you from continuing with your project. Hoping you contribute a welcome paradigm shift in the world of ebike technology progress!

I gave the example of an AWD drive in a car because most sports models have an AWD drive to improve stability and transfer high power. Such a car is harder to skid and easier to control. However, such structures are actually expensive, heavy and complicate the construction. In a bicycle, adding a front hub does not complicate the construction, there are no gears, driveshafts, shafts, bridges, and other elements that cause power losses. The 350W front hub weighs 2 kg and is not a heavy burden. However, on steep climbs, even a small amount of torque on the front wheel can greatly reduce the load on the rear wheel drive.

 

[Aloles]

One thing you should keep in mind though is the power balance between the two motors, on my 2WD bike I can easily spin the front wheel in low/mid traction conditions because the front will always have less traction than the rear (unless you're going down a real steep hill or the conditions under each tire are different). When this happens the bike becomes very unstable similar to locking up the front brake. This is only a problem if the front motor has more power than traction available. So low traction and/or high power. Since I have matching front and rear hub motors I solved it by just enabling the traction control function on the VESCs driving. With the small front motor you are planning it probably won't be an issue but is something to think about.

Thank you very much for your valuable attention. Losing traction on the front wheel is very dangerous and unacceptable. Therefore, tests should be carried out and the front hub support levels should be selected in such a way that there is no risk. Interesting idea with the ASR (Acceleration Slip Regulation) traction control. However, it is an ABS-based system and the whole thing looks expensive and complicated. I think that the amount of support force on the front wheel must be associated with the terrain inclination sensor.

 

[scianiac]

With only a 350w motor in the front it probably won't be an issue in normal riding conditions, in my case it's a fat bike designed to ride in deep snow and ice so traction is always at a premium and with large Bafang G062 motors driven as hard as I dare. In my case I specifically picked matching motors and a dual vesc so all I had to do to turn on the traction control is press 1 button but it is a rather rudimentary system in that all it does is reduce power to a motor if it starts spinning faster than the other which is normally fast enough in deep snow and ice but probably would be scary at high speeds.

You can also of course make sure the weight distribution is ideal by placing the battery as low as possible and farther forward, within limits of course. Your idea of adjusting the front wheel torque based on incline is interesting though, probably could be done with a lisp script on a vesc since the system to connect the gyro and accelerometer is already there. I've been considering someday building a hyperlight front wheel drive system that could be used for slow speed rock crawling and I think the control of it would be the key to making it work, that and making it light enough with the needed very high gear reduction.

 

[offGridDownUnder]

increase efficiency in the field and stability on the road

This helps as it provides some idea of the sort of riding you want to design for, although it also seems to say "everything". That's not quite true - it doesn't suggest extreme off-road or high-speed on road.

Are you thinking of regenerative braking in this design? I've converted a 20" wheel road bike to front hub Grin All-Axle motor, and a 26" Cruzbike to rear drive using a (front hub) Grin All-Axle motor, with pedal powered front wheel (they're built backwards - search for pictures). Now I'm riding a Greenspeed Magnum Big Wheel tadpole with a rear hub motor mounted as a mid-drive (which permits me to vary the 'gearing' reduction between the motor and the 26" rear wheel).

I could slip the front wheel on the road bike going up hill, but for braking force, the front wheel was optimal.
The rear drive on the Cruzbike was very good for going up hills. My weight meant the rear wheel also worked for regenerative braking - it did not slip.

I've tried two motors so far on the trike - a GMAC and now a Shengyi SX2. Both (with gearing) can propel me up 12% (measured) grades, but the Shengyi does not provide the full regenerative braking that the GMAC can. It is much quieter.

Apart from the Shengyi, the motors could bring me to a stop with all of these conversions without engaging the mechanical brakes even on a steep hill - albeit over a slightly longer distance. The Shengyi will stop me on level or modest down slopes - but the difference is notable. The mechanical brakes stop the soonest for panic stops, but the regenerative braking was always within sensible distances when riding on the road.

This suggests to me that you weight your choice of front motor towards something that provides adequate regeneration but perhaps less torque for up-hill, and focus the rear motor more on the heavy lifting for up-hill. I don't know about the motors you mention (and you may have already purchased them). From my limited experience (outlined above) I would put a Grin All-Axle on the front as it should have a much longer life than the GMAC (and weigh less) while providing excellent braking and being suitable for level speed work.

For my different criteria, I would put a hub motor on the back - either a GMAC, or perhaps another All-Axle. I hesitate on the All-Axle as I'd want to analyze the loads and torques and speeds to be certain it would be adequate. The GMAC will definitely lift a heavy bike + rider so I would use that as a rear drive motor - but analyze to confirm your own criteria.

 

[neptronix]

I'd consider a pair of small geared motors for this application.

Here's the current efficiency champion of geared hub motors climbing a 10% grade, no sweat. Might overheat in 10 minutes of this, but, it could handle lesser grades for long periods of time.. if your terrain is not too steep, this might be a better setup.



If you had a pair of controllers you could run the rear motor a little hotter than the front ( considering the front wheel has less traction ), and also delay the time the front motor gets started, then i believe it would be possible to control both by linking the throttle ( ask grin - i think it's possible ).

This would give you nice single throttle AWD.

As far as getting torque vectoring, ABS, or any other fancy features, i don't know of any controllers capable of supporting that. I think that an arduino module could be built that could read wheel speeds and modulate both throttles, and the logic to help support that wouldn't be too complex. I don't think i've seen anyone on the forum go that far though.

 

[Aloles]

This helps as it provides some idea of the sort of riding you want to design for, although it also seems to say "everything". That's not quite true - it doesn't suggest extreme off-road or high-speed on road.

Are you thinking of regenerative braking in this design? I've converted a 20" wheel road bike to front hub Grin All-Axle motor, and a 26" Cruzbike to rear drive using a (front hub) Grin All-Axle motor, with pedal powered front wheel (they're built backwards - search for pictures). Now I'm riding a Greenspeed Magnum Big Wheel tadpole with a rear hub motor mounted as a mid-drive (which permits me to vary the 'gearing' reduction between the motor and the 26" rear wheel).

I could slip the front wheel on the road bike going up hill, but for braking force, the front wheel was optimal.
The rear drive on the Cruzbike was very good for going up hills. My weight meant the rear wheel also worked for regenerative braking - it did not slip.

I've tried two motors so far on the trike - a GMAC and now a Shengyi SX2. Both (with gearing) can propel me up 12% (measured) grades, but the Shengyi does not provide the full regenerative braking that the GMAC can. It is much quieter.

Apart from the Shengyi, the motors could bring me to a stop with all of these conversions without engaging the mechanical brakes even on a steep hill - albeit over a slightly longer distance. The Shengyi will stop me on level or modest down slopes - but the difference is notable. The mechanical brakes stop the soonest for panic stops, but the regenerative braking was always within sensible distances when riding on the road.

This suggests to me that you weight your choice of front motor towards something that provides adequate regeneration but perhaps less torque for up-hill, and focus the rear motor more on the heavy lifting for up-hill. I don't know about the motors you mention (and you may have already purchased them). From my limited experience (outlined above) I would put a Grin All-Axle on the front as it should have a much longer life than the GMAC (and weigh less) while providing excellent braking and being suitable for level speed work.

For my different criteria, I would put a hub motor on the back - either a GMAC, or perhaps another All-Axle. I hesitate on the All-Axle as I'd want to analyze the loads and torques and speeds to be certain it would be adequate. The GMAC will definitely lift a heavy bike + rider so I would use that as a rear drive motor - but analyze to confirm your own criteria.

This helps as it provides some idea of the sort of riding you want to design for, although it also seems to say "everything". That's not quite true - it doesn't suggest extreme off-road or high-speed on road.

Are you thinking of regenerative braking in this design? I've converted a 20" wheel road bike to front hub Grin All-Axle motor, and a 26" Cruzbike to rear drive using a (front hub) Grin All-Axle motor, with pedal powered front wheel (they're built backwards - search for pictures). Now I'm riding a Greenspeed Magnum Big Wheel tadpole with a rear hub motor mounted as a mid-drive (which permits me to vary the 'gearing' reduction between the motor and the 26" rear wheel).

I could slip the front wheel on the road bike going up hill, but for braking force, the front wheel was optimal.
The rear drive on the Cruzbike was very good for going up hills. My weight meant the rear wheel also worked for regenerative braking - it did not slip.

I've tried two motors so far on the trike - a GMAC and now a Shengyi SX2. Both (with gearing) can propel me up 12% (measured) grades, but the Shengyi does not provide the full regenerative braking that the GMAC can. It is much quieter.

Apart from the Shengyi, the motors could bring me to a stop with all of these conversions without engaging the mechanical brakes even on a steep hill - albeit over a slightly longer distance. The Shengyi will stop me on level or modest down slopes - but the difference is notable. The mechanical brakes stop the soonest for panic stops, but the regenerative braking was always within sensible distances when riding on the road.

This suggests to me that you weight your choice of front motor towards something that provides adequate regeneration but perhaps less torque for up-hill, and focus the rear motor more on the heavy lifting for up-hill. I don't know about the motors you mention (and you may have already purchased them). From my limited experience (outlined above) I would put a Grin All-Axle on the front as it should have a much longer life than the GMAC (and weigh less) while providing excellent braking and being suitable for level speed work.

For my different criteria, I would put a hub motor on the back - either a GMAC, or perhaps another All-Axle. I hesitate on the All-Axle as I'd want to analyze the loads and torques and speeds to be certain it would be adequate. The GMAC will definitely lift a heavy bike + rider so I would use that as a rear drive motor - but analyze to confirm your own criteria.

This helps as it provides some idea of the sort of riding you want to design for, although it also seems to say "everything". That's not quite true - it doesn't suggest extreme off-road or high-speed on road.

Are you thinking of regenerative braking in this design? I've converted a 20" wheel road bike to front hub Grin All-Axle motor, and a 26" Cruzbike to rear drive using a (front hub) Grin All-Axle motor, with pedal powered front wheel (they're built backwards - search for pictures). Now I'm riding a Greenspeed Magnum Big Wheel tadpole with a rear hub motor mounted as a mid-drive (which permits me to vary the 'gearing' reduction between the motor and the 26" rear wheel).

I could slip the front wheel on the road bike going up hill, but for braking force, the front wheel was optimal.
The rear drive on the Cruzbike was very good for going up hills. My weight meant the rear wheel also worked for regenerative braking - it did not slip.

I've tried two motors so far on the trike - a GMAC and now a Shengyi SX2. Both (with gearing) can propel me up 12% (measured) grades, but the Shengyi does not provide the full regenerative braking that the GMAC can. It is much quieter.

Apart from the Shengyi, the motors could bring me to a stop with all of these conversions without engaging the mechanical brakes even on a steep hill - albeit over a slightly longer distance. The Shengyi will stop me on level or modest down slopes - but the difference is notable. The mechanical brakes stop the soonest for panic stops, but the regenerative braking was always within sensible distances when riding on the road.

This suggests to me that you weight your choice of front motor towards something that provides adequate regeneration but perhaps less torque for up-hill, and focus the rear motor more on the heavy lifting for up-hill. I don't know about the motors you mention (and you may have already purchased them). From my limited experience (outlined above) I would put a Grin All-Axle on the front as it should have a much longer life than the GMAC (and weigh less) while providing excellent braking and being suitable for level speed work.

For my different criteria, I would put a hub motor on the back - either a GMAC, or perhaps another All-Axle. I hesitate on the All-Axle as I'd want to analyze the loads and torques and speeds to be certain it would be adequate. The GMAC will definitely lift a heavy bike + rider so I would use that as a rear drive motor - but analyze to confirm your own criteria.

This design is by no means intended for extreme riding. I just wanted to demonstrate that the AWD drive is not only used in off-road vehicles. It is often used in family station wagons and VANs to maintain safety in more difficult conditions often encountered on roads, snow, people, rain. The motor I am considering for the front hub is AKM-100H 48V 350W (I mentioned it in the first post). Hasn't been purchased yet. First, a lot of thinking, designing, carefully listening to advice on what and how to do it, and then shopping, assembly and testing. I do not plan on recuperation because the engines I intend to use do not provide such a possibility. The bike that will be converted to 2WD is MTB UNIBIKE FUSION, 19" frame, 29" wheel, SCHWALBE SMART SAM / 29X2.25 tire. Currently, I have installed a TSDZ2B 500W 48V+OSF engine, a 48V 15Ah battery, a range of +120 km in easy terrain.
I deliberately chose cheap but good equipment to prove that a good bike, even for riding in difficult conditions, does not have to cost $3-5-10k. The vast majority of users do not drive acrobatically or racing. However, the trend resulting from the climate is that skis and snowboards are increasingly being replaced with e-bikes.

 

[Aloles]

I'd consider a pair of small geared motors for this application.

Here's the current efficiency champion of geared hub motors climbing a 10% grade, no sweat. Might overheat in 10 minutes of this, but, it could handle lesser grades for long periods of time.. if your terrain is not too steep, this might be a better setup.

View attachment 352247

If you had a pair of controllers you could run the rear motor a little hotter than the front ( considering the front wheel has less traction ), and also delay the time the front motor gets started, then i believe it would be possible to control both by linking the throttle ( ask grin - i think it's possible ).

This would give you nice single throttle AWD.

As far as getting torque vectoring, ABS, or any other fancy features, i don't know of any controllers capable of supporting that. I think that an arduino module could be built that could read wheel speeds and modulate both throttles, and the logic to help support that wouldn't be too complex. I don't think i've seen anyone on the forum go that far though.

Thank you for your suggestion. However, I have to stick with the mid drive. I really like the TSDZ + OSF support and it gives me great driving pleasure. I believe that the journey is not the one to overcome, but that it is the goal. Currently, I use the bike on normal terrain, but I am going to the mountains and long steep climbs on the trails may be a problem for the TSDZ. The problem of using a bicycle in such conditions concerns not only the TDSZ engine and its temperature. Cassettes, chains, bottom brackets and pins in the moving elements of the rear suspension wear out quickly. Therefore, I believe that 2WD should significantly reduce problems. I have a few questions about this. Will one 48V 15 Ah max 30A battery handle both engines (TSDZ and AKM) without any problems? Is simple branching enough? Will the TSDZ controller work with the AKM engine? The idea is to use the same driver for AKM as for TSDZ. Then one VLCD 5 display and one strain gauge are enough to operate both engines.

 

[neptronix]

Allright.

You will end up with two controllers and have to design something to link them to provide AWD or orchestrate that if you want. A big problem though is that the mid drive's torque per mph is highly variable but the geared motor's is not, you can imply a lot from the throttle position.

Yes the downside of mid drive is that the drive is always more expensive than a hub and it also tends to wear out bike parts, adding to the expense. The mid drive also has lots of wear items in it too and a cheap one will need replacement parts over it's lifetime.

Yes, you can offset some of this wear using a front hub motor.

 

[99t4]

Will one 48V 15 Ah max 30A battery handle both engines (TSDZ and AKM) without any problems?

Depends. What is the max amperage draw of both controllers combined?