Storm
100 W
- Joined
- Aug 27, 2007
- Messages
- 108
The E-cumbent - A project by Matt Shumaker
- Thread starter Storm
- Start date
RLT
10 kW
An actual thread title instead of a . would be useful.
But other than that, a very impressive bit of work!
I wonder how it will work out in the long run
I was struck by this statement:
HA! I have about 300 hours into my 2WD project and another hundred to go before I finish MK2, probably. Although admittedly half of the time spent has been fixing things that either W.E. or I messed up the first time.
But other than that, a very impressive bit of work!
I wonder how it will work out in the long run
I was struck by this statement:
HA! I have about 300 hours into my 2WD project and another hundred to go before I finish MK2, probably. Although admittedly half of the time spent has been fixing things that either W.E. or I messed up the first time.
EMF
100 kW
I'd like to see a picture of this 48 volt - 10 amp hour Lithium pack that weighs 70 oz. 
Sumpin' tells me there is a problem with these figures somewhere. My 80 cell 8 amp hour 66 volt A123 weighs about 15-16 pounds- Edit: Although the A123 are heavy.
I also suppose that little motor if geared correctly could drive a bike, but I am skeptical as it takes quite a bit of torque to haul 220+ pounds around, accelerate and also fight wind resisitance hills etc. Good luck with that. Maybe these new fangled airplane motors can do it, I've been out of RC for many years.
Please post some videos when you get this puppy on the tarmac.
Having said that, you are quite the machinist and I can tell you are into helis the minute I saw that motor cage. I also like the gates style timing belt rather than these chain drives. Quiet and smooth running. Good job.
Sumpin' tells me there is a problem with these figures somewhere. My 80 cell 8 amp hour 66 volt A123 weighs about 15-16 pounds- Edit: Although the A123 are heavy.I also suppose that little motor if geared correctly could drive a bike, but I am skeptical as it takes quite a bit of torque to haul 220+ pounds around, accelerate and also fight wind resisitance hills etc. Good luck with that. Maybe these new fangled airplane motors can do it, I've been out of RC for many years.
Please post some videos when you get this puppy on the tarmac.
Having said that, you are quite the machinist and I can tell you are into helis the minute I saw that motor cage. I also like the gates style timing belt rather than these chain drives. Quiet and smooth running. Good job.
Lessss
1 MW
Looks good. Alot of tech I don't understand, but it shows we are really over paying for the technology we are using now.
Ben
100 W
Dang, that's cool.
It'll be interesting to see how it turns out.
Looks like we're due for an update soon too.
It'll be interesting to see how it turns out.
Looks like we're due for an update soon too.
Malcolm
10 kW
Very impressive build. I'm really looking forward to seeing how he gets on with this motor as this is an idea that a few of us have toyed with at some stage. It just confirms to me that one of the biggest obstacles to electric vehicle development – from ebikes right the way up to cars – is suitable lightweight gearing solutions. What we need ideally are lightweight two-speed gearboxes with a reduction ratio of around 10:1
That is very nice machine work. I'll be interested in hearing more on road testing.
I bet it sort of sounds like an electric drill when it runs.
I bet it sort of sounds like an electric drill when it runs.
mvadventure
1 kW
- Joined
- May 2, 2007
- Messages
- 419
Wow, it's absolutely amazing what youth, talent, technology, drive, skill, imagination, a whole bunch of tools and desire can accomplish. I'm impressed and perhaps mostly impressed with the time frame. Am looking forward to the completed project and the results, good or bad it's gotta be great.
Mike
Mike
Dr. Shock
100 W
- Joined
- Dec 28, 2007
- Messages
- 274
Very nice work. I was intrigued by the youtube vid which everyone's seen of a bike powered by an RC motor. As these things are now available in high voltage low rpm configurations, it's about time somebody made a good ebike drive from them. I really want to see how that tiny controller stands up. Keep us posted, please!
Drunkskunk
100 GW
Nice Bike!
a year ago you couldn't have done this. the motors and controllers were too low of voltage, too high of current, too high of RPM, and needed speed to keep cool. Amazing how things change in such a short time. this being a 4000 watt system, imagine how compact he could have build a 750 watt system.
a year ago you couldn't have done this. the motors and controllers were too low of voltage, too high of current, too high of RPM, and needed speed to keep cool. Amazing how things change in such a short time. this being a 4000 watt system, imagine how compact he could have build a 750 watt system.
Drunkskunk
100 GW
Nice Bike!
a year ago you couldn't have done this. the motors and controllers were too low of voltage, too high of current, too high of RPM, and needed speed to keep cool. Amazing how things change in such a short time. this being a 4000 watt system, imagine how compact he could have build a 750 watt system.
a year ago you couldn't have done this. the motors and controllers were too low of voltage, too high of current, too high of RPM, and needed speed to keep cool. Amazing how things change in such a short time. this being a 4000 watt system, imagine how compact he could have build a 750 watt system.
Hello
Really nice job indeed, reminds me of the Lemco machining we did years ago on the Lemco bike, some very nice machine work there, a few pointers for you though having done loads of different builds, the chain wont handle 4KW of power! not a chance, it will snap very quickly or wear very quickly, the Lemco bike I did was a big version of your setup in many ways, also the BMX sprocket pawls dont last long if you really gun it, if you can i would program a shallow ramp in to the controller as I fear it wont last long with all that power we killed a lot of chain. Another problem I can see is the wheel, what gauge spokes are you running? and how is that sprocket fixed exactly? its a lot of torque to put through the base of those spokes, hub motors circumvent this as the torque is delivered higher up inside the wheel allowing shorter spokes, I broke spokes so regularly and 3 went when cornering under power it tacoed the wheel and spat me off the bike, part of the reason I dont run systems like that anymore, bike components are not made IMHO for more than 1 to 1.5KW of power more than this and you want to consider beefing things up.
I dont want that to take away from what an amazing job that you have done though simply brilliant, please let us know how you get on and what problems you come across, you will be doing very well to get 50mph though you will need 3KW, more like 4KW when you take in to account the loss of motor and gearbox efficiency at 48V thats 62A thats over 3C rating in each pack on those cells!! dont know the spec but they should be ok however it will use them up very quickly as you can see! those copter motors are noisy as well is this a problem?
Really great to see a build like this though, with your expert machining skills though you could also tweak some of the cheaper e-bike packages so they work better, thanks so much for sharing your build with us all here and please post some video of it in action.
Knoxie
Really nice job indeed, reminds me of the Lemco machining we did years ago on the Lemco bike, some very nice machine work there, a few pointers for you though having done loads of different builds, the chain wont handle 4KW of power! not a chance, it will snap very quickly or wear very quickly, the Lemco bike I did was a big version of your setup in many ways, also the BMX sprocket pawls dont last long if you really gun it, if you can i would program a shallow ramp in to the controller as I fear it wont last long with all that power we killed a lot of chain. Another problem I can see is the wheel, what gauge spokes are you running? and how is that sprocket fixed exactly? its a lot of torque to put through the base of those spokes, hub motors circumvent this as the torque is delivered higher up inside the wheel allowing shorter spokes, I broke spokes so regularly and 3 went when cornering under power it tacoed the wheel and spat me off the bike, part of the reason I dont run systems like that anymore, bike components are not made IMHO for more than 1 to 1.5KW of power more than this and you want to consider beefing things up.
I dont want that to take away from what an amazing job that you have done though simply brilliant, please let us know how you get on and what problems you come across, you will be doing very well to get 50mph though you will need 3KW, more like 4KW when you take in to account the loss of motor and gearbox efficiency at 48V thats 62A thats over 3C rating in each pack on those cells!! dont know the spec but they should be ok however it will use them up very quickly as you can see! those copter motors are noisy as well is this a problem?
Really great to see a build like this though, with your expert machining skills though you could also tweak some of the cheaper e-bike packages so they work better, thanks so much for sharing your build with us all here and please post some video of it in action.
Knoxie
Ben
100 W
Now I'm confused. Storm, is this your project?
Storm said:
Sorry, got it...
Yeah it cool. I don't know why this guy thinks that the RC market is cheaper then ebikes though. If anything, its more expensive then ebike stuff. I wasted way to much dough on RC toy airplanes and cars and transmitters. Looking back on it all now, I could have had multiple ebike kits to haul me around instead of playing with toys. 
Storm
100 W
- Joined
- Aug 27, 2007
- Messages
- 108
Matt has added some more information down the page including the adaptor for the rear sprocket.
Hopefully we'll get some ride reports soon.
http://www.wisil.recumbents.com/wisil/shumaker/default.htm
Hopefully we'll get some ride reports soon.
http://www.wisil.recumbents.com/wisil/shumaker/default.htm
vanilla ice
1 MW
That rear hub looks a little sketchy for 5hp.
recumpence
1 GW
Hey Guys!
Glad to be a part of this forum. OK, lots of questions. I will try to answer them as I can.
The motor and drive system sounds unique. the motor itself is basically silent other than the windings pulsing. The belts have a sort of quiet, muffled supercharger whine. Interesting, but not obtrusive. I have not run the bike yet. But, my CNC runs the same style motor (though smaller) with a belt drive. So I have an idea how it will sound.
These motors are super efficient. Therefore they run cool and with a HUGE amount of power per pound of weight. I have a different motor in an RC car that is 1/4 the weigh of this motor and 90% as much power. That motor (a Neu1515) is up to 97% efficient. So, I am hopeful it will be fine. If heat ever becomes an issue, AXI makes a fan that mounts to the rear of the motor and spins with the can.
I was concerned about the torque on the spokes also. I actually have an extra $500 sitting here to buy a CF Spin or Aerospoke wheel with disc brake flange for the left sprocket if I wreck this wheel. That being said, I just had to see if this wheel will hold up. My thought was this, I have a mountain bike with a 24 spoke 26 inch wheel and disc brakes. I crank on the front brake and do endoes all the time and have never had a spoke problem. So, I do not see this wheel getting more torque put to the spokes than that wheel. Of course, my logic may be fatally flawed. That is why I am holding some cash for a decent wheel if need be. :wink:
I went with a BMX chain because it was conveient. Also, you can buy super heavy duty chains that were designed for sprocket grinding on freestyle bikes. I will go that route if I need to. Also, my sprocket is 7075 aluminum it was a nightmare to machine! It should hold up. If not, hello steel sprocket!
The ESC (speed control) will have no problem at all. I have 3 of those same controllers. They run nice and cool up to 127 amps at 48 volts in one application I have. I have never had a problem with one no matter how hard I push it. I can program a soft start/throttle ramp as well (it is USB programmable). I will probably program in a delay to ease the driveline load. Also, there are a couple guys in the UK that are running similar setups (though much smaller) with great success. I just found this out a couple days ago. Funny how you think you are the first to try something.............
The cells are 10C cells. I cycled them and confirmed this. the pack will weigh 80 ounces with wiring and casing. This may seem impossibly light from E-bike standards. But, actually from an RC standpoint, there are cells that are lighter with better ratings, but they are HUGELY costly!
I appreciate the kudos on the project and the machining. I am self taught and have very basic machines (and small). I sold a spare car we had to buy it all and taught myself everything. I even program in G-code!
Please forgive my general ignorance in E-bike technology. I am knowledgeable in bike building (I had one hand made bike featured in BMX Plus when I was 20) and RC. but, not in E-bike per-se. But, I was surprised how expensive everything was. Not that it costs a fortune to setup an E-bike. But, it is alot of money for the ratings of what you can get in typical E-bike equipment. I am not trying to insult E-bikes (hub motors, etc). I am just frustrated that there is so little in the way of true technology applied to this hobby/sport by the majority of manufacturers. I had one e-recumbent designer contact me Wednesday. He is sending up a rep to see my bike (for ideas?). Weird. I haven't even run it yet. But, that tells me there is a pent up desire for better e-bike technology. Is this the future of e-bikes? I doubt it. But, it may be a step in the right direction. I just need to get it running and see!
Who knows, it may be a flop. But, I have done alot of research on this. I may have ratios a bit off or some other bugs here or there. But, the bike should perform quite well.
Then again, this may prove to be a huge waste of time!
Matt
Glad to be a part of this forum. OK, lots of questions. I will try to answer them as I can.
The motor and drive system sounds unique. the motor itself is basically silent other than the windings pulsing. The belts have a sort of quiet, muffled supercharger whine. Interesting, but not obtrusive. I have not run the bike yet. But, my CNC runs the same style motor (though smaller) with a belt drive. So I have an idea how it will sound.
These motors are super efficient. Therefore they run cool and with a HUGE amount of power per pound of weight. I have a different motor in an RC car that is 1/4 the weigh of this motor and 90% as much power. That motor (a Neu1515) is up to 97% efficient. So, I am hopeful it will be fine. If heat ever becomes an issue, AXI makes a fan that mounts to the rear of the motor and spins with the can.
I was concerned about the torque on the spokes also. I actually have an extra $500 sitting here to buy a CF Spin or Aerospoke wheel with disc brake flange for the left sprocket if I wreck this wheel. That being said, I just had to see if this wheel will hold up. My thought was this, I have a mountain bike with a 24 spoke 26 inch wheel and disc brakes. I crank on the front brake and do endoes all the time and have never had a spoke problem. So, I do not see this wheel getting more torque put to the spokes than that wheel. Of course, my logic may be fatally flawed. That is why I am holding some cash for a decent wheel if need be. :wink:
I went with a BMX chain because it was conveient. Also, you can buy super heavy duty chains that were designed for sprocket grinding on freestyle bikes. I will go that route if I need to. Also, my sprocket is 7075 aluminum it was a nightmare to machine! It should hold up. If not, hello steel sprocket!
The ESC (speed control) will have no problem at all. I have 3 of those same controllers. They run nice and cool up to 127 amps at 48 volts in one application I have. I have never had a problem with one no matter how hard I push it. I can program a soft start/throttle ramp as well (it is USB programmable). I will probably program in a delay to ease the driveline load. Also, there are a couple guys in the UK that are running similar setups (though much smaller) with great success. I just found this out a couple days ago. Funny how you think you are the first to try something.............
The cells are 10C cells. I cycled them and confirmed this. the pack will weigh 80 ounces with wiring and casing. This may seem impossibly light from E-bike standards. But, actually from an RC standpoint, there are cells that are lighter with better ratings, but they are HUGELY costly!
I appreciate the kudos on the project and the machining. I am self taught and have very basic machines (and small). I sold a spare car we had to buy it all and taught myself everything. I even program in G-code!
Please forgive my general ignorance in E-bike technology. I am knowledgeable in bike building (I had one hand made bike featured in BMX Plus when I was 20) and RC. but, not in E-bike per-se. But, I was surprised how expensive everything was. Not that it costs a fortune to setup an E-bike. But, it is alot of money for the ratings of what you can get in typical E-bike equipment. I am not trying to insult E-bikes (hub motors, etc). I am just frustrated that there is so little in the way of true technology applied to this hobby/sport by the majority of manufacturers. I had one e-recumbent designer contact me Wednesday. He is sending up a rep to see my bike (for ideas?). Weird. I haven't even run it yet. But, that tells me there is a pent up desire for better e-bike technology. Is this the future of e-bikes? I doubt it. But, it may be a step in the right direction. I just need to get it running and see!
Who knows, it may be a flop. But, I have done alot of research on this. I may have ratios a bit off or some other bugs here or there. But, the bike should perform quite well.
Then again, this may prove to be a huge waste of time!
Matt
Malcolm
10 kW
Hi Matt
Excellent first post! Totally agree with you on the lack of technology in this area, so it's really good to see someone pushing the boundaries. I'm sure I'm not the only one who's keen to hear how this works out for you before trying out something similar themselves. Good to hear your comments about noise and temperature, as these were two issues that concerned me. I've been looking around for simple off-the-shelf gearing systems for this type of motor for a while, but not come up with anything ideal. I guess from the fact that you've gone to all this trouble to build your own that you don't know of any suitable bolt-on gear reductions (planetary drives), or would they be too noisy?
Excellent first post! Totally agree with you on the lack of technology in this area, so it's really good to see someone pushing the boundaries. I'm sure I'm not the only one who's keen to hear how this works out for you before trying out something similar themselves. Good to hear your comments about noise and temperature, as these were two issues that concerned me. I've been looking around for simple off-the-shelf gearing systems for this type of motor for a while, but not come up with anything ideal. I guess from the fact that you've gone to all this trouble to build your own that you don't know of any suitable bolt-on gear reductions (planetary drives), or would they be too noisy?
safe
1 GW
- Joined
- Dec 22, 2006
- Messages
- 5,681
recumpence said:
Hey that's interesting... now that should make you about middle forties now right?I've been into this bicycle road racing idea all this time and I'm trying to make my best attempt at bringing the idea to life.
Look for the "Safe's Ancient History Thread"... you will have some fun with it. I had an article in "Bicycles and Dirt" magazine, which changed names a few times and then died out at about the same time.
lawsonuw
1 kW
recumpence said:
Huh, I've always found the harder grades of aluminum easier to machine. The softer grades of aluminum gum up on parts and tool bits causing all kinds of problems. Though, the smallest milling machine I've ever used is a Bridgeport 1 knockoff manual mill
Also Machinery's Handbook, this book is on my short list of reference books to buy. As far as keeping the belt/chain alive, I think that will be a matter of avoiding drive line shock (throttle ramps) and keeping the motor current limited to some safe value. Looking at your latest pictures I think your hub-sprocket adapter is plenty strong. I'd guess that the tire will spin on the rim, or spokes will break first. Probably the best thing that can be done to make a gear-box tough is to add a friction-overload clutch. I learned this the hard way making gearboxes for my battlebots
. Marty
lazarus2405
10 kW
I'm not sure where you looked to gain your understanding of the state of ebike technology, but I'll agree that it is certainly underdeveloped. By RC standards, most of the parts are hugely heavy for their rated power, and inefficient, and with some notable exceptions crappy kits are sold at outrageous prices. However, there is plenty of good kit mixed in there, if you just know where to look. Ebike motors aren't wound anything like quality RC motors, controllers generally improve because of quality issues that shouldn't have been issues in the first place, and each company has its own color/connector/measuring standards. The bright spot is battery technology, off which ebike tech can simply piggyback.
Of course, part of the problem is regulatory. Most hub motors are vastly underrated in their power output, able to handle continuously perhaps twice their rated power and three times or more in bursts. But when a company sells a conversion kit with a 2.5kw motor in a regulatory climate that considers above 750w to be illegal on an unregistered bike, they face quite the liability. (This is where you get some of the odd power output math, like "48v 40a 750w"). But, a large part of it is technical.
The problem just boils down to hub motors, and price tradeoffs. Direct drive forces them to operate at low RPMs, where power per unit weight and efficiency are just pure crap compared to good RC motors. The geared systems have their own sets of problems, particularly the added price. Chain drives are even more expensive to get right. So, the heavy hub motors are a trade-off of that. In most cases, it's simply more economical to invest in more battery capacity than increased motor efficiency. Because bikes are far less sensitive to weight than RC applications, this is not an issue (ebike components, unlike RC parts, are never measured in ounces or grams).
I don't mean to criticize your build when I say this, but what you're doing is, technically speaking, outrageously expensive. The custom work is great (beautiful, really), but it simply doesn't make sense for the vast majority of ebike applications. Almost always it is a better compromise, because of cost or a lack of machine skills or other factors, to trade efficiency and weight for lower material, labor, and manufacturing costs.
Anyway, specific to your build:
I really like how the RC components are very very compact. Keeping everything under the seat will be very stealthy. Kudos on that, it'll be gorgeous.
I think you'd better carefully consider your desired top speed. You'll have the aerodynamics to do over 50mph on 2kw, but if you gear for a 50mph top speed, you'll rarely be riding in the motor's peak efficiency range. Not to mention the pure comfort issues of going that fast with no suspension. I'd suggest gearing for more like a 30-35mph top speed, which will let you ride around town with 5%-15% better efficiency and give you more thrust for acceleration and hills.
I figure that you'll only use the full 4kw of the motor in bursts for acceleration (incredibly fun, btw), since 4kw at 80% efficiency will heat up that little motor pretty darn fast. You won't need it to go fast on a midrider bent. You can maximize that hotrod feeling by gearing for as low of a top speed as you can be happy with. Then let that motor loose to burn rubber as necessary.
Of course, part of the problem is regulatory. Most hub motors are vastly underrated in their power output, able to handle continuously perhaps twice their rated power and three times or more in bursts. But when a company sells a conversion kit with a 2.5kw motor in a regulatory climate that considers above 750w to be illegal on an unregistered bike, they face quite the liability. (This is where you get some of the odd power output math, like "48v 40a 750w"). But, a large part of it is technical.
The problem just boils down to hub motors, and price tradeoffs. Direct drive forces them to operate at low RPMs, where power per unit weight and efficiency are just pure crap compared to good RC motors. The geared systems have their own sets of problems, particularly the added price. Chain drives are even more expensive to get right. So, the heavy hub motors are a trade-off of that. In most cases, it's simply more economical to invest in more battery capacity than increased motor efficiency. Because bikes are far less sensitive to weight than RC applications, this is not an issue (ebike components, unlike RC parts, are never measured in ounces or grams).
I don't mean to criticize your build when I say this, but what you're doing is, technically speaking, outrageously expensive. The custom work is great (beautiful, really), but it simply doesn't make sense for the vast majority of ebike applications. Almost always it is a better compromise, because of cost or a lack of machine skills or other factors, to trade efficiency and weight for lower material, labor, and manufacturing costs.
Anyway, specific to your build:
I really like how the RC components are very very compact. Keeping everything under the seat will be very stealthy. Kudos on that, it'll be gorgeous.
I think you'd better carefully consider your desired top speed. You'll have the aerodynamics to do over 50mph on 2kw, but if you gear for a 50mph top speed, you'll rarely be riding in the motor's peak efficiency range. Not to mention the pure comfort issues of going that fast with no suspension. I'd suggest gearing for more like a 30-35mph top speed, which will let you ride around town with 5%-15% better efficiency and give you more thrust for acceleration and hills.
I figure that you'll only use the full 4kw of the motor in bursts for acceleration (incredibly fun, btw), since 4kw at 80% efficiency will heat up that little motor pretty darn fast. You won't need it to go fast on a midrider bent. You can maximize that hotrod feeling by gearing for as low of a top speed as you can be happy with. Then let that motor loose to burn rubber as necessary.
recumpence
1 GW
Great replys!
Thanks alot, guys. I feel very welcome here (much more so than the Yahoo groups I am a member of).
I agree my setup is not a very good example of something easily repeatable. Also, yes my setup is not innexpensive. But, I figured if I am going to blow alot of money on E-bike stuff, I may as do what I really want to do no matter how much time it takes to do the machining. This is a one-off, high end project bike. If I had to make multiple bikes, I would do it in a much simpler way. But, hey, this if fun!
If you look at the web page, I decided to go with lower geearing to begin with. This s very easy to chaneg as I get it sorted out. I have the power for high speed, but, yes, if I put around at 20 mph while geared for 50 or 55, it will be wasting energy as heat.
I am hoping for the stealth look. But, admittedly, I like the bling factor too. Maybe some removeable carbon fiber side guards to hid teh shiney drive components would be good?!
Also, yes, I looked into planetary reductions. They are noisey and make the motor too long.
I love the hub motor concept. But, I wanted to try this.
Oh, I know a guy in one of my RC forums, that pulls 2,600 watts through his hub motored bike on 70 volts. It bent his forks while spinnign the front tire. Very cool! So, yes, I am sure the hub motors are under rated.
Oh, I am 36 years old. If you want to look up the BMX Plus artical, it was in the 1991 issue. The artical is titled "Project Home made" I ran across it recently doing som on-line searching. I believe it was the October issue. Oh, I had a car featured in Auto Sounds and Security magazine too (5 page feature) for my SPL car. That is the car I sold to buy my machining equipment.
I have had that "15 minutes in the sun" twice, you could say. :wink:
I tend to do weird/unique stuff. It generates exposure. Hmm, does that feed my ego? Not a chance!
It any rate, I appreciate the input and advice. I agree with pretty much everything you guys have said. Like I mentioned before, I am not very familiar with E-bike standard equipment nearly to the degree I am familiar with RC and bicycles.
Thanks for the kind welcome.
Matt
Thanks alot, guys. I feel very welcome here (much more so than the Yahoo groups I am a member of).
I agree my setup is not a very good example of something easily repeatable. Also, yes my setup is not innexpensive. But, I figured if I am going to blow alot of money on E-bike stuff, I may as do what I really want to do no matter how much time it takes to do the machining. This is a one-off, high end project bike. If I had to make multiple bikes, I would do it in a much simpler way. But, hey, this if fun!
If you look at the web page, I decided to go with lower geearing to begin with. This s very easy to chaneg as I get it sorted out. I have the power for high speed, but, yes, if I put around at 20 mph while geared for 50 or 55, it will be wasting energy as heat.
I am hoping for the stealth look. But, admittedly, I like the bling factor too. Maybe some removeable carbon fiber side guards to hid teh shiney drive components would be good?!
Also, yes, I looked into planetary reductions. They are noisey and make the motor too long.
I love the hub motor concept. But, I wanted to try this.
Oh, I know a guy in one of my RC forums, that pulls 2,600 watts through his hub motored bike on 70 volts. It bent his forks while spinnign the front tire. Very cool! So, yes, I am sure the hub motors are under rated.
Oh, I am 36 years old. If you want to look up the BMX Plus artical, it was in the 1991 issue. The artical is titled "Project Home made" I ran across it recently doing som on-line searching. I believe it was the October issue. Oh, I had a car featured in Auto Sounds and Security magazine too (5 page feature) for my SPL car. That is the car I sold to buy my machining equipment.
I have had that "15 minutes in the sun" twice, you could say. :wink:
I tend to do weird/unique stuff. It generates exposure. Hmm, does that feed my ego? Not a chance!
It any rate, I appreciate the input and advice. I agree with pretty much everything you guys have said. Like I mentioned before, I am not very familiar with E-bike standard equipment nearly to the degree I am familiar with RC and bicycles.
Thanks for the kind welcome.
Matt
recumpence
1 GW
http://www.23mag.com/mags/bpl/bpl92.htm
Here's one link.
Matt
Here's one link.
Matt
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