Kepler
10 MW
MrDude_1 said:
No, an 80-100 wont fit. Way too big for an under bottom bracket mount. Motors are cheap though so just get the right motor for the job. The links a few posts ago are both good choices. I personally favour the 63-54.
Kepler Friction drive comes of age.
- Thread starter Kepler
- Start date
No, an 80-100 wont fit. Way too big for an under bottom bracket mount. Motors are cheap though so just get the right motor for the job. The links a few posts ago are both good choices. I personally favour the 63-54.
JTL
10 W
Kepler, so how fast would a FD go? Say compared to a BBSHD all other things being equal.
Kepler
10 MW
On my road bike I can maintain 35 kph to 40 kph on a low powered 250W setup. With a 500W setup, maintaining 50 kph on a light load bike setup would be quite possible.
1JohnFoster
100 W
subscribed
aCeMadMod
1 kW
hi i don't know if seen my pm, did you like any my bikes
and cost ti Kepler Friction drive comes of age.
revs
thank you
and cost ti Kepler Friction drive comes of age.
revs
thank you
Kepler
10 MW
Yes I have checked out your bikes. They look amazing. Your motorised road-bike will be far better off with a light weight friction drive in my opinion.
Cost of the drive mechanics is $98 USD. $15 USD postage to USA and Europe.
Cost of the drive mechanics is $98 USD. $15 USD postage to USA and Europe.
Kepler
10 MW
Here is another good choice for the drive if you like the idea of 63mm motor. This is about the cheapest motor I have found so far in the 63mm range. I have used Keda motors on friction drive a lot. Found them to be very reliable.
https://hobbyking.com/en_us/kd-53-20-brushless-outrunner-195kv.html
I am going to try and fit a 63-74 to the drive today. Stay tuned.
https://hobbyking.com/en_us/kd-53-20-brushless-outrunner-195kv.html
I am going to try and fit a 63-74 to the drive today. Stay tuned.
Kepler
10 MW
Also the 3 prototype drives offered have now all gone.
Good new is that 5 new style prototypes get laser cut next week. With a bit of luck, these will be the production items but just need to make sure I am 100% satisfied with design.
Good new is that 5 new style prototypes get laser cut next week. With a bit of luck, these will be the production items but just need to make sure I am 100% satisfied with design.
how hard you engage motor in to the tire ?
when i experimenting (it was 63 mm outer diameter motor) in few weeks motor starts working strange then i find that can with the magnets came loose in place where its connects to motor shaft and magnates start to hit stator when i engage motor in to tire (but i push 1000w-3000w in my friction drive and i need to engage motor really hard to not slip when accelerate)
solution was to use motors with skirt bearing only and 2 years no problems with the motor
you with around 300w power i think don't have this problem?
when i experimenting (it was 63 mm outer diameter motor) in few weeks motor starts working strange then i find that can with the magnets came loose in place where its connects to motor shaft and magnates start to hit stator when i engage motor in to tire (but i push 1000w-3000w in my friction drive and i need to engage motor really hard to not slip when accelerate)
solution was to use motors with skirt bearing only and 2 years no problems with the motor
you with around 300w power i think don't have this problem?
Kepler
10 MW
I set the drives to climb and push into the tire just hard enough if you hold the motor still while it is fully engaged and try turn the tire you can only just make slip with significant effort.
Never had a motor bearing fail however, you are right, I only use about 350W max. I have run up to 700W on previous drives though without any bearing problems.
1000W - 3000W is some serious power for a friction drive, something this drive is definitely not designed for.
Never had a motor bearing fail however, you are right, I only use about 350W max. I have run up to 700W on previous drives though without any bearing problems.
1000W - 3000W is some serious power for a friction drive, something this drive is definitely not designed for.
Kepler said:
i have problems with place where motor shaft press fit to the can with magnets and this press fit came lose
my letest build is 7000w motor friction drive (but can deliver only around 5000w because don't have enough powerful controller) (and its lightest e bike with such power in my country)
Kepler
10 MW
You should start a separate thread on your high powered friction drive. I am sure it would generate quite a bit of interest.
ScooterMan101
1 MW
Which motor is the 500 watt one ? I would want that at the very least , 600 + watt would be better to get me up Hills
( for me a little heaver and more visible is not a problem at all , I need plenty of power to go up hills )
Center of BB to outside of tire on my Road Bike is 70mm
Center of BB to outside of tire/road tire , on my MTB is 84mm
Could there be two options
A higher speed motor for road bike ?
and
A lowerspeed but the Highest Torque Friction Drive motor for the MTB for off road slower speed with a emphasis on hill climbing ability ?
With a 500-600 + watt version of the drive you are designing,
what would be the battery ( Hobby Lipo ) to get 6s ?
7s ? or 8 s ?
( I now see that the 63-54 motor that you prefer can operate on 22.4-44-8 volts,
So is there a difference in what speed we would get , according to the amount of cells, just like in hub motors the more volts the more speed ?)
If so I wonder what the difference would be between a 6s pack to a 7s pack to a 8s pack to two 6s packs in series ?
Or
Would a increase in cells from 6 to 7 to 8 to 12 , just not affect the speed, but rather just give us more watt hours ?
( for me a little heaver and more visible is not a problem at all , I need plenty of power to go up hills )
Center of BB to outside of tire on my Road Bike is 70mm
Center of BB to outside of tire/road tire , on my MTB is 84mm
Could there be two options
A higher speed motor for road bike ?
and
A lowerspeed but the Highest Torque Friction Drive motor for the MTB for off road slower speed with a emphasis on hill climbing ability ?
With a 500-600 + watt version of the drive you are designing,
what would be the battery ( Hobby Lipo ) to get 6s ?
7s ? or 8 s ?
( I now see that the 63-54 motor that you prefer can operate on 22.4-44-8 volts,
So is there a difference in what speed we would get , according to the amount of cells, just like in hub motors the more volts the more speed ?)
If so I wonder what the difference would be between a 6s pack to a 7s pack to a 8s pack to two 6s packs in series ?
Or
Would a increase in cells from 6 to 7 to 8 to 12 , just not affect the speed, but rather just give us more watt hours ?
Kepler
10 MW
If you want 600 Watts, the 63-53 200kv motor suits best. It will do more then 600W of course but 600W would be its max continuous (in my opinion).
the 63-54 200kv will be fast enough for both bikes In fact the speed will be same. As explained previously, wheel diameter is irrelevant to friction drives.
Battery wise go 6S LiPo or 7S 18650
You need to keep the voltage down to keep the motor RPM and subsequent speed reasonable. If you throw enough amps at the motor it will do 50kph on both bikes. 600W will give you all the speed you ever need. I get 50kph out of my road bike at 350W peak with me helping of course.
the 63-54 200kv will be fast enough for both bikes In fact the speed will be same. As explained previously, wheel diameter is irrelevant to friction drives.
Battery wise go 6S LiPo or 7S 18650
You need to keep the voltage down to keep the motor RPM and subsequent speed reasonable. If you throw enough amps at the motor it will do 50kph on both bikes. 600W will give you all the speed you ever need. I get 50kph out of my road bike at 350W peak with me helping of course.
Hyall
Im a bit of a lurker and I just wanted to post this: http://diyelectricskateboard.com/diy-electric-skateboard-kits-parts/vesc-the-best-electric-skateboard-esc/
Seems to be a opensource bldc controller that can drive a motor up to 2kw, and start one without sensors. Has regenerative braking aswell.
Maybe would setting the drive into regenerative braking be enough to drop the motor from the tire. Instead of trying to overpower it by pedaling.
Also, are there any issues with dirt and moisture on these motors? As it seems like coils are basically open.
EDIT: Should have done the research better, VESC has been mentioned like 10 times in this thread alone already... Sorry.
Im a bit of a lurker and I just wanted to post this: http://diyelectricskateboard.com/diy-electric-skateboard-kits-parts/vesc-the-best-electric-skateboard-esc/
Seems to be a opensource bldc controller that can drive a motor up to 2kw, and start one without sensors. Has regenerative braking aswell.
Maybe would setting the drive into regenerative braking be enough to drop the motor from the tire. Instead of trying to overpower it by pedaling.
Also, are there any issues with dirt and moisture on these motors? As it seems like coils are basically open.
EDIT: Should have done the research better, VESC has been mentioned like 10 times in this thread alone already... Sorry.
Kepler
10 MW
Hi Radam, thanks for chiming in. The vesc that you have linked to is a controller we are already looking at very closely at. I think it is going to be a great fit for the drive and look forward to testing one in the very near future.
In relation to dirt and moisture, you need to remember that these motors are brushless outrunners. This means they can actually run under water. Fill it full of mud. Just hose it out. That being said, The drive doesn't work in wet weather unless you add grip tape to the can because the metal surface of the drive will slip on the tire. My rational is just dont use it in the rain. Easy for me living in a dry climate but I understand that my ebike buddies living in wet climates need to be confident the drive will work in wet weather. Bottom line is that it is no problems for the motor. Its more about sealing the controller and associate electronics.
In relation to dirt and moisture, you need to remember that these motors are brushless outrunners. This means they can actually run under water. Fill it full of mud. Just hose it out. That being said, The drive doesn't work in wet weather unless you add grip tape to the can because the metal surface of the drive will slip on the tire. My rational is just dont use it in the rain. Easy for me living in a dry climate but I understand that my ebike buddies living in wet climates need to be confident the drive will work in wet weather. Bottom line is that it is no problems for the motor. Its more about sealing the controller and associate electronics.
ScooterMan101
1 MW
Great Work Kepler !
I am calculating that 2 to 3 6s batteries in Parallel would get me the milage/distance I want to go.
Perfect , just a little under 6 pounds of batteries. ( Just over 5 pounds for the batteries, and a little under 1 pound for custom made battery case / holder , made strong , that fits on the down tube )
The Road Bike I have , with the Q100c cst , Is built up as a flat bar road bike, I have been wanting to change to Drop Bar / STI Shifter/Brake ,
But
The thumb throttle fits and works fine on a flat bar, however when I look at what a few others have done to try and make the thumb throttle on
a Drop Bar, the way of zip tying it near the shifters just is not ergonomically comfortable !
I have been waiting to go to a drop bar until ... someone develops a throttle more like a pot box , like a light switch dimmer, only not round nob
rather a slide, small enough to fit right onto the brake lever.
Up motion speeds up , and Down motion slows down / to stop. that way when you grab the brake lever and pull in you are also pulling down to slow/stop the motor .
This of course would work even better when designed as a touch pad , pressing the upper pad speeds up, pressing on the lower pad further down on the brake lever slows down.
Another way possible is to use the joy stick that is on a RC Transmitter Box.
In all the different ways I see possibilities, keep in mind that the two ways should have some friction to them so that we can stop at any position to achievecruise control.
With the thin Mouse Pad idea on the brake lever this would be done electronically . in increments of 1km or a little less . Press the upper pad until the desired speed is reached then when taking off pressure the throttle stays at that position/speed.
I am calculating that 2 to 3 6s batteries in Parallel would get me the milage/distance I want to go.
Perfect , just a little under 6 pounds of batteries. ( Just over 5 pounds for the batteries, and a little under 1 pound for custom made battery case / holder , made strong , that fits on the down tube )
The Road Bike I have , with the Q100c cst , Is built up as a flat bar road bike, I have been wanting to change to Drop Bar / STI Shifter/Brake ,
But
The thumb throttle fits and works fine on a flat bar, however when I look at what a few others have done to try and make the thumb throttle on
a Drop Bar, the way of zip tying it near the shifters just is not ergonomically comfortable !
I have been waiting to go to a drop bar until ... someone develops a throttle more like a pot box , like a light switch dimmer, only not round nob
rather a slide, small enough to fit right onto the brake lever.
Up motion speeds up , and Down motion slows down / to stop. that way when you grab the brake lever and pull in you are also pulling down to slow/stop the motor .
This of course would work even better when designed as a touch pad , pressing the upper pad speeds up, pressing on the lower pad further down on the brake lever slows down.
Another way possible is to use the joy stick that is on a RC Transmitter Box.
In all the different ways I see possibilities, keep in mind that the two ways should have some friction to them so that we can stop at any position to achievecruise control.
With the thin Mouse Pad idea on the brake lever this would be done electronically . in increments of 1km or a little less . Press the upper pad until the desired speed is reached then when taking off pressure the throttle stays at that position/speed.
Kepler
10 MW
Now it is obvious that I am a fan of friction drives. I think their true potential is only now being unlocked. That being said, I think it is important that anyone contemplating a friction drive goes in with their eyes open and armed with as much information as possible.
With this in mind I have put together a video of the way my road bike performs with my friction drive using a 63-54 236kv motor, a cheap KU65 250W controller, 24V nominal, a simple throttle pushbutton interface. In regards to power, we[youtube][/youtube] are talking 350W peak and 200W nominal. Nothing exciting but if you take the time to watch the video, you may well be surprised just how useful such a small assist can be. The low assist level means small batteries and light weight. With the pack I am running I get 70 minutes full time assist. When used only when needed, this equates to massive range out of a 200 Whr battery. I regularly do 80km rides on 200Whrs and arrive home feeling fresh.
I have been very careful to preserve the true sound this friction drive makes. Its not quiet but i think some will be surprised to hear that it really isn't as bad some would make it out to be. That being said, I believe the noise level is the only true hurdle left to conquer. I am working on this and with the advent of FOC Skateboard controllers, I think we my well be very close. A reduction of 50% in noise level would be all we need to be totally under the radar.
Anyway, enough of my rant. I hope the video is of interest and assists with keeping the friction drive revolution moving forward.
[youtube]BeiiP3iHapE[/youtube]
With this in mind I have put together a video of the way my road bike performs with my friction drive using a 63-54 236kv motor, a cheap KU65 250W controller, 24V nominal, a simple throttle pushbutton interface. In regards to power, we[youtube][/youtube] are talking 350W peak and 200W nominal. Nothing exciting but if you take the time to watch the video, you may well be surprised just how useful such a small assist can be. The low assist level means small batteries and light weight. With the pack I am running I get 70 minutes full time assist. When used only when needed, this equates to massive range out of a 200 Whr battery. I regularly do 80km rides on 200Whrs and arrive home feeling fresh.
I have been very careful to preserve the true sound this friction drive makes. Its not quiet but i think some will be surprised to hear that it really isn't as bad some would make it out to be. That being said, I believe the noise level is the only true hurdle left to conquer. I am working on this and with the advent of FOC Skateboard controllers, I think we my well be very close. A reduction of 50% in noise level would be all we need to be totally under the radar.
Anyway, enough of my rant. I hope the video is of interest and assists with keeping the friction drive revolution moving forward.
[youtube]BeiiP3iHapE[/youtube]
Kepler
10 MW
Attempted to fit a 63-74 motor to drive. Unfortunately it is too wide for the lefthand crank to clear.
So that's a fail however look what just turned up on my desk. Skateboard hub motor. Should be interesting.
So that's a fail however look what just turned up on my desk. Skateboard hub motor. Should be interesting.
Kepler
10 MW
Very cool work Kepler!
The Phaserunner FOC is very quiet compared to an Infineon Trapwave.
On my MAC under 100 watts on a Recumbent its silent.
A true FOC usually takes a secondary processor. Not all Sinewave drivers are FOC. There may be others but the only true FOC I know of is the TI 83xx family with a Piccolo. I've been trying to find out which driver is in the Phaserunner (ASI) but no one wants to speak up.
In any event its bound to be very quiet with the right driver.
The Phaserunner FOC is very quiet compared to an Infineon Trapwave.
On my MAC under 100 watts on a Recumbent its silent.
A true FOC usually takes a secondary processor. Not all Sinewave drivers are FOC. There may be others but the only true FOC I know of is the TI 83xx family with a Piccolo. I've been trying to find out which driver is in the Phaserunner (ASI) but no one wants to speak up.
In any event its bound to be very quiet with the right driver.
ScooterMan101
1 MW
For many reasons,
First I do not ride either On / or Off . Also when putting pressure on any item like a spring loaded switch / thumb throttle / twist throttle , that part of the hand
( muscles and tendons ) gets sore and numb .
The more years you have on your body the more you are susceptible to things like Tendinitis, Carpal Tunnel , Sore Muscles, Sore Tendons, having to put constant pressure on a button would produce Tendinitis in a short amount of time.
Add to that
When riding with others ( cyclists that have no e-motor ) they ride try to ride at a constant speed, but sometimes they go a little harder for a little while, then back off to give themself's a bit of a rest while still pedalilng , and the slight difference can often be matched by me shifting a few gears and/or pedaling a little harder or a little less.
so having a switch ( button switch , or toggle switch ) for just On or OFF just would Not Work
Also
I learned many years ago with my first electric scooter, that even a thumb throttle , the way it is designed has a couple of
Flaws, First with a Spring Loaded Thumb Throttle you Thumb gets sore in short order. So you don't ride , or ride just
a little, Also , With a Spring Loaded Thumb Throttle when you hit a bump / go over a pot hole/ go over ruff ground,
your speed speeds up or slows down too suddenly. Not good when riding with others you will either ride right into them or the ones behind will run into you . not good in either case.
I have ridden bikes for 5 decades, and the best way to ride a electric assist bike , is to have a throttle with cruise control.
What you do is use the throttle to get to the speed you want to maintain, then use the cruise feature, then match your gears front and rear to what your legs and cardiovascular system can handle that day. You also turn off the cruise feature for short periods as well.
The amount of effort I can put into the cranks changes every day.
Add to that that I have arthritis / tendinitis in both knees, one knee chronically with allot of pain every time I ride a bike, and especially when I ride a bike without any assist,
Now you see the need for not only a throttle , a throttle with cruise control.
What I have done with my thumb throttle on the Road Bike since there is no cruise control button like on the infineon controllers.
is that I took out the spring, then put in some white athletic tape on the inside to cause just a small amount of stiction.
That way when I get to the speed I want , or need to be at , I leave the position there, and again I adjust the gears for how much assist I will be giving the motor, that way I can speed up a little by pedaling harder, or lighter to slow down a little.
So Electric Assist, just in Reverse order , Which by the way Works Much Much Better.
First I do not ride either On / or Off . Also when putting pressure on any item like a spring loaded switch / thumb throttle / twist throttle , that part of the hand
( muscles and tendons ) gets sore and numb .
The more years you have on your body the more you are susceptible to things like Tendinitis, Carpal Tunnel , Sore Muscles, Sore Tendons, having to put constant pressure on a button would produce Tendinitis in a short amount of time.
Add to that
When riding with others ( cyclists that have no e-motor ) they ride try to ride at a constant speed, but sometimes they go a little harder for a little while, then back off to give themself's a bit of a rest while still pedalilng , and the slight difference can often be matched by me shifting a few gears and/or pedaling a little harder or a little less.
so having a switch ( button switch , or toggle switch ) for just On or OFF just would Not Work
Also
I learned many years ago with my first electric scooter, that even a thumb throttle , the way it is designed has a couple of
Flaws, First with a Spring Loaded Thumb Throttle you Thumb gets sore in short order. So you don't ride , or ride just
a little, Also , With a Spring Loaded Thumb Throttle when you hit a bump / go over a pot hole/ go over ruff ground,
your speed speeds up or slows down too suddenly. Not good when riding with others you will either ride right into them or the ones behind will run into you . not good in either case.
I have ridden bikes for 5 decades, and the best way to ride a electric assist bike , is to have a throttle with cruise control.
What you do is use the throttle to get to the speed you want to maintain, then use the cruise feature, then match your gears front and rear to what your legs and cardiovascular system can handle that day. You also turn off the cruise feature for short periods as well.
The amount of effort I can put into the cranks changes every day.
Add to that that I have arthritis / tendinitis in both knees, one knee chronically with allot of pain every time I ride a bike, and especially when I ride a bike without any assist,
Now you see the need for not only a throttle , a throttle with cruise control.
What I have done with my thumb throttle on the Road Bike since there is no cruise control button like on the infineon controllers.
is that I took out the spring, then put in some white athletic tape on the inside to cause just a small amount of stiction.
That way when I get to the speed I want , or need to be at , I leave the position there, and again I adjust the gears for how much assist I will be giving the motor, that way I can speed up a little by pedaling harder, or lighter to slow down a little.
So Electric Assist, just in Reverse order , Which by the way Works Much Much Better.
Kepler said:
Pranav.ptl
1 mW
- Joined
- Jan 13, 2017
- Messages
- 11
Performance looks good! What battery pack are you using for the video based performance?
Kepler
10 MW
I am using a custom built 7S3P 18650 pack using Panasonic 35E cells.The picture below is 25R's but changed over to 35E's to improve range as current draw wasn't an issue with a 14A controller. Here is a link to the thread detailing the bike build that is featured in the video. https://endless-sphere.com/forums/viewtopic.php?f=6&t=74269
Attachments
telcosteve
10 mW
- Joined
- Dec 15, 2016
- Messages
- 20
fantastic work and video Kepler! I cant wait to get my drive installed. I am not having much luck with the whole arduino thing and will probably just do a button like you did. so cool!!!
so if I do an on/off button with my castle 90 speed control could I build that same circuit that you did with the capacitor for ramp down or would I need to change values. I love technology and circuits but am honestly not very talented at it.
on the servo tester it seems really smooth and not sure how I wire up an on off switch but cant be that hard I guess?
I think I can build a basic analog circuit following directions but not so much on the programming. sounds like that VESC will be the ticket but after watching the video I am thinking a simple on off would be fine for me.
also on my castle speed control I got a programming chip that I can modify ramp up and other features so maybe that will allow some customization.
Keep up the good work.
so if I do an on/off button with my castle 90 speed control could I build that same circuit that you did with the capacitor for ramp down or would I need to change values. I love technology and circuits but am honestly not very talented at it.
on the servo tester it seems really smooth and not sure how I wire up an on off switch but cant be that hard I guess?
I think I can build a basic analog circuit following directions but not so much on the programming. sounds like that VESC will be the ticket but after watching the video I am thinking a simple on off would be fine for me.
also on my castle speed control I got a programming chip that I can modify ramp up and other features so maybe that will allow some customization.
Keep up the good work.
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