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Electric Bicycle Road Racer (R&D)
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safe
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RC Brushless Motor
I've been delaying this decision as long as I could, but while I plan to give my best attempt to get my old bike up and going with a brushed motor I've come to the realization that for something like an Electric Bicycle Road Racer it makes sense to go that extra step and switch to brushless because they are (of course) better motors overall and having no commutator to break they are less likely to fail.
For one thing you can select from a variety of RC motors that have different rpm/volt numbers so the need for custom rewinding goes away because it comes down to shopping for the right configuration. It's far easier to shop than to build yourself.
The only glitch in the RC motors is that the throttle is a little funky to get right. There's a guy that is selling custom throttle kits for about $100 and another guy that is also selling them that has now been forced to drop his prices to $100. From what I can tell the circuit is about as hard as my old Armature Current Limiting circuit, so I might just build one of my own.
On my own circuit I'll preset the current limit so that the combined value of the voltage and current is close to the 1000 Watt limit I want for a racing class. Most of the failures of the RC motors appear to be because the stock ESC's don't limit the current very well.
So far I'm looking at:
Motor - $53.19
ESC (controller) - $43.95
Servor Tester Circuit - $5.74
...and many of the circuit parts I already have laying around and they only cost a few dollars anyway. So the total will be about $100 and the motor will be able to handle the "regulation legal" power of 1000W input with ease. (the motor is rated as 2100W)
The nasty and tricky part is going to be the integration of the RC motor with my MY1016Z3 geardown unit. I think that a custom motor spindle would do the trick... but I'm far from solving that at this point. It's always those tricky details that can set you back days or weeks.
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I've been working on the fiberglass the last few days... it should improve the aerodynamics a great deal...
I've been delaying this decision as long as I could, but while I plan to give my best attempt to get my old bike up and going with a brushed motor I've come to the realization that for something like an Electric Bicycle Road Racer it makes sense to go that extra step and switch to brushless because they are (of course) better motors overall and having no commutator to break they are less likely to fail.
For one thing you can select from a variety of RC motors that have different rpm/volt numbers so the need for custom rewinding goes away because it comes down to shopping for the right configuration. It's far easier to shop than to build yourself.
The only glitch in the RC motors is that the throttle is a little funky to get right. There's a guy that is selling custom throttle kits for about $100 and another guy that is also selling them that has now been forced to drop his prices to $100. From what I can tell the circuit is about as hard as my old Armature Current Limiting circuit, so I might just build one of my own.
On my own circuit I'll preset the current limit so that the combined value of the voltage and current is close to the 1000 Watt limit I want for a racing class. Most of the failures of the RC motors appear to be because the stock ESC's don't limit the current very well.
So far I'm looking at:
Motor - $53.19
ESC (controller) - $43.95
Servor Tester Circuit - $5.74
...and many of the circuit parts I already have laying around and they only cost a few dollars anyway. So the total will be about $100 and the motor will be able to handle the "regulation legal" power of 1000W input with ease. (the motor is rated as 2100W)
The nasty and tricky part is going to be the integration of the RC motor with my MY1016Z3 geardown unit. I think that a custom motor spindle would do the trick... but I'm far from solving that at this point. It's always those tricky details that can set you back days or weeks.
--------------------------
I've been working on the fiberglass the last few days... it should improve the aerodynamics a great deal...
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safe
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Front Fender -> Aerodynamic Airplug
I started this front fender project two weeks ago and it's been one of those incredibly complex parts to make. My goal was to keep the weight down, so I did it with paper thin amounts of fiberglass. It has many very tricky things to get right and I really didn't know what it would be until I actually built it. (it evolved along the way)
The central concept is that since my EBRR (Electric Bicycle Road Racer) does not use a radiator there is no reason to allow airflow between the forks. Also, without suspension I can plug the hole up completely. This should (in theory) reduce my effective frontal area by about 100 square centimeters or so. The air now reroutes around the front wheel and goes out to the sides and the fender will also reduce the backwards flowing air that you get from the tire itself. I'm expecting some good results... whenever I get the bike running.
I started this front fender project two weeks ago and it's been one of those incredibly complex parts to make. My goal was to keep the weight down, so I did it with paper thin amounts of fiberglass. It has many very tricky things to get right and I really didn't know what it would be until I actually built it. (it evolved along the way)
The central concept is that since my EBRR (Electric Bicycle Road Racer) does not use a radiator there is no reason to allow airflow between the forks. Also, without suspension I can plug the hole up completely. This should (in theory) reduce my effective frontal area by about 100 square centimeters or so. The air now reroutes around the front wheel and goes out to the sides and the fender will also reduce the backwards flowing air that you get from the tire itself. I'm expecting some good results... whenever I get the bike running.
safe
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Looks like I'm going to have to take some time off from this hobby and spend some time working on house related maintenance for a few weeks. Owning a big house seemed like a good idea once, but after about a decade it's now in need of some serious work.
Bummer...
Eventually I'll get back to this project...
johnrobholmes
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bodywork looks great.
The cheaper sensorless ESCs have trouble keeping sync under varying load. Don't get discouraged if this happens you you.
The cheaper sensorless ESCs have trouble keeping sync under varying load. Don't get discouraged if this happens you you.
safe
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My house repairs mean that I'm not going to be able to do anything for some time. I had been letting things pile up for years and now it's just to the point where I have to get all the problems fixed. (there are many) The one I'm dealing with now is a dishwasher that was leaking water and that water got into a bunch of sheet rock which means it all needs replacing to prevent mold.
Hopefully the "bleeding edge" of RC motors or other motors will evolve so that next season I can have a better shot at getting it all together. Adapting the RC motor to my ebike is not going to be easy and just getting the gearing to work will be tough. I'd like to play with the existing brushed motor for a while. (the existing motor does work on the new bike)
This year started off well... got the new bike running... but then I destroyed the Sturmey Archer 8-Speed rear hub (almost immediately) and then on my old bike I've struggled with motors becoming unglued and falling apart. The only new record I made for the old bike was to pull 60 mph for a short time downhill. That compares with 58 mph on the same hill the year before. (2 mph difference and that was it)
It's looking like practical reality is forcing me to look towards next season already.
Ever since about May of this year I've been working constantly on the ebikes... so that's May, June, July... now it's August and I just can't devote any more time to it this year until get the house fixed up.
The great thing about hobbies is that "there is always next year". (no deadlines)
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Note: The little riding time I did get on this new Road Racer bike was excellent. The handling is perfect and even before the front fender the aerodynamics were already super slick. When it's finally completed it's going to be a great bike. Most people focus all their energies into one isolated component like the motor or the transmission, but I'm trying to accomplish something that is so unique and operates as a unit so that it's really in "it's own reality". The bike "feels" right... so one day...
One day... one day... :dozey:
Hopefully the "bleeding edge" of RC motors or other motors will evolve so that next season I can have a better shot at getting it all together. Adapting the RC motor to my ebike is not going to be easy and just getting the gearing to work will be tough. I'd like to play with the existing brushed motor for a while. (the existing motor does work on the new bike)
This year started off well... got the new bike running... but then I destroyed the Sturmey Archer 8-Speed rear hub (almost immediately) and then on my old bike I've struggled with motors becoming unglued and falling apart. The only new record I made for the old bike was to pull 60 mph for a short time downhill. That compares with 58 mph on the same hill the year before. (2 mph difference and that was it)
It's looking like practical reality is forcing me to look towards next season already.
Ever since about May of this year I've been working constantly on the ebikes... so that's May, June, July... now it's August and I just can't devote any more time to it this year until get the house fixed up.
The great thing about hobbies is that "there is always next year". (no deadlines)
----------------------
Note: The little riding time I did get on this new Road Racer bike was excellent. The handling is perfect and even before the front fender the aerodynamics were already super slick. When it's finally completed it's going to be a great bike. Most people focus all their energies into one isolated component like the motor or the transmission, but I'm trying to accomplish something that is so unique and operates as a unit so that it's really in "it's own reality". The bike "feels" right... so one day...
One day... one day... :dozey:
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safe
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Conversion
My plan is to convert this bike from something with gears and geardowns to the lightweight and efficient Halbach Disc Motor. In order to prepare for the conversion I needed to alter the frame.
This is the cleaned up area that was once a motor mount and has now been ground smooth and resupported:
...this is the new motor mount for the Halbach Disc Motor.
My plan is to convert this bike from something with gears and geardowns to the lightweight and efficient Halbach Disc Motor. In order to prepare for the conversion I needed to alter the frame.
This is the cleaned up area that was once a motor mount and has now been ground smooth and resupported:
...this is the new motor mount for the Halbach Disc Motor.
You have to be careful when shifting under load, or any time there is much torque. You really shouldn't be shifting under any torque.
When I'm cycling on my road bike, I instinctively know exactly when and for how long to ease on the pedals when I shift. Since I am the motor there, I can precisely bring chain tension to near 0, shift completely, then go back into full throttle (sprinting or whatever) - all within about .3 seconds.
Now, when it comes to shifting my ebike - that's another story. It's hard to begin with since I still have the shifter and throttle on the right - need to fix that. But I also had a problem last week when I shifted with the chain spinning at about 120rpms. It tends to slap sideways a bit when shifted at high speed, so that time it hit the motor drivetrain to the left, and caught on it. Then it got jammed between the two. I'm going to remount my front derailer just to act as a chain guard.
But back to your case - it is widely known that you shouldn't shift under load. It will vastly increase your chances of breaking the chain. That reminds me - last night I did a real hard sprint up a hill last night on my road bike. The gear wasn't sitting perfectly and it jumped I think - broke my chain. It's probably the only the 2nd time I've broken a chain in 60,000 pedal miles. And I sprint like a madman all the time. The only reason it broke was because it jumped. I was lucky, 3 other cyclists saw me and stopped to help, and I was lucky to have my master link on me.
When I'm cycling on my road bike, I instinctively know exactly when and for how long to ease on the pedals when I shift. Since I am the motor there, I can precisely bring chain tension to near 0, shift completely, then go back into full throttle (sprinting or whatever) - all within about .3 seconds.
Now, when it comes to shifting my ebike - that's another story. It's hard to begin with since I still have the shifter and throttle on the right - need to fix that. But I also had a problem last week when I shifted with the chain spinning at about 120rpms. It tends to slap sideways a bit when shifted at high speed, so that time it hit the motor drivetrain to the left, and caught on it. Then it got jammed between the two. I'm going to remount my front derailer just to act as a chain guard.
But back to your case - it is widely known that you shouldn't shift under load. It will vastly increase your chances of breaking the chain. That reminds me - last night I did a real hard sprint up a hill last night on my road bike. The gear wasn't sitting perfectly and it jumped I think - broke my chain. It's probably the only the 2nd time I've broken a chain in 60,000 pedal miles. And I sprint like a madman all the time. The only reason it broke was because it jumped. I was lucky, 3 other cyclists saw me and stopped to help, and I was lucky to have my master link on me.
safe
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I haven't been very good about updating this thread... but I'm going to try to spend more time on it as the bike comes together.
I've dropped the idea of multispeed gears for now in favor of the Halbach Disc Motor idea, so all the problems related to gears are for the time being not a current concern.
Maybe I could have posted on my Halbach Disc Motor thread instead, but this is the actual bike it's going on and the recent work was on it's frame.
Sorry for any confusion.
I've dropped the idea of multispeed gears for now in favor of the Halbach Disc Motor idea, so all the problems related to gears are for the time being not a current concern.
Maybe I could have posted on my Halbach Disc Motor thread instead, but this is the actual bike it's going on and the recent work was on it's frame.
Sorry for any confusion.
happycheapskate
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Shimano makes a group with a 9 tooth high gear on a cassette and dedicated hub. Its made for 20" wheels and recumbents or folding bikes.
Are those real pictures of your bike or a digital mockup? It looks like an electric Pocketbike. I like it.
Are those real pictures of your bike or a digital mockup? It looks like an electric Pocketbike. I like it.
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