new eZip motor

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It is for submarines and weighs 4.4 tons. However that is a 2007 article. lord only knows what is being invented today. All I know is heat is a major factor in DC electric motor power output. I learned that when I burned up the Currie motor and almost fried the controller.

DA. You are correct about air cooling being the norm. at this point in time! However as the demands for extremely high output DC motors for race car applications like over 1 million watts I am sure that liquid cooling will become the new norm. in the research and development area. Thanks.

LC out.
 
DrkAngel said:
Well ... you seem to be progressing.

Starting with simple dreams of power and speed ... without proper consideration of safety or survivability ...
Now you present ludicrous musings of unattainable and unusable(!) power ... by ridiculous methods.

Try some reality!
Take your 20incher, add a speedometer and throw 100lb of lead into the baskets.
Go to the top of the steepest hill you can find and let gravity give you a taste of your desired 50 mph.

Please have someone ahead of you filming! HD camera that captures your facial expression when you realize what an awful mistake you are making, desired.
Slo-mo for the probable outcome ... please.
Please provide cameraman with your ES account info, so the movie can be posted up, in case you become ... permanently unavailable.

Not fast or unsafe enough ... ?
Roller blades and a rocket strapped to your butt is the next logical step?
Come on DA we both said the same thing in different words. We post our concern but you know he's gonna do what he's gonna do anyway!

GOOD LUCK LC it's been fun following you progress?!

Dan
 
latecurtis said:
http://global-sei.com/sn/2007/361/4.html

Don't laugh too hard DA Here is a 365 kilowatt motor cooled by liquid nitrogen. I looked it up.
Wow ... ?
"<HTS Motor Specifications>
Output: 365 kW, Motor rotation speed:
250 rpm,
Dimensions: 1.2 m (diameter) x 0.8 m (length),
Weight: 4.4 tons "

489 HP from 8800 lb motor ... about the size of a hottub ...
And that doesn't include the coolant system ... almost as large again and a few thousand lb more?

file.php


Try sticking that under your hood!

.
 
If you want to build a monster electric car ...
Check out The White Zombie = "the World's Fastest Street Legal Car" - 1/4 mile trap speed.
0-60 in ~ 1.8 seconds, 1/8 mile ET 6.443 @ 108.63 mph!

file.php
 

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Frying the Currie was due to running hard at inefficient speed.
Guessing ...
You went 36V (675w output) for 27mph
(36V 28A controller)
But took it up a hill at 7.5 mph 25% efficient range ... without helping by pedaling!:
1000w input with 250w motor output for 4 minutes = 750w heat for 4 minutes = 3000w heat
Even modest pedaling might have kept motor speed in 50%+ efficient range (15 mph):
1000w input with 500w motor output for 2 minutes = 500w heat for 2 minutes = 1000w heat
See - Attack them Hills!

Motors should be additionally rated with an "effective heat dissipation" rating

E.G. Unite MY1018z 450w motor 24V 35A controller
500w electricity into 450w motor @ 80% efficiency = 400w physical power and 100w heat output (20 mph) at peak efficiency
840w electricity into 450w motor @ 50% efficiency = 420w physical power and 420w heat output (10mph)
840w electricity into 450w motor @ 25% efficiency = 210w physical power and 630w heat output (5mph)
Reasonable "effective heat dissipation" might be 100w and maximum might be 200w (sustainable)

Catastrophic failure likely occurred because you were exceeding 500w heat output for several minutes, creating cumulative heat, resulting in a melt down-burn up.

Gearing for top speed destroys low speed power and efficiency!
Pedal assisting, especially at lower speeds can be extremely effective!
See - Attack them Hills!
 
View attachment mandown.mp4


sorry LCs in bad shape. we rescued his camera to convert it . he gave me the log on a while back. i told him to wait till he got brakes. He don't listen to me. Its too bad.. The other guys really banged up too.. ill find something out by tomorrow If LC makes it?
later
LCs bike buddy
 
Well ... he was having fun!
 
What an idiot!
Riding against traffic:
1. is illegal
2. gives vehicles and you <1/2 the time to react properly
3. turns a 30 - 20 = 10mph rear impact into a 30 + 20 = 50mph frontal impact
4. pedestrians have no logical-legal reason to look to their right before stepping off the curb

LC was warned on multiple counts, so he got what he deserved
Poor-no brakes
Unreasonable speed
Riding against traffic


Sad about the pedestrian, not sure if he can sue LC for the majority of his disability checks?
Doesn't seem to have a great amount of personal property to sue for?
 
LC's buddy is a dumbbell too for posting the video. It'll be good evidence against LC in civil court.
 
Well it finally happened. Wonder if he had loaded up his bike with rocks and went to the top of the hill and tried riding down with no brakes. Hummm I believe he was told that he should have brakes on his bike while riding.

But, I am sorry to hear that he had an accident and on top of that hurt someone else. Poor guy.

I would say that maybe he learned something, but I doubt it. He seems to be pretty headstrong on doing things his way. And his way isn't always the best.

Guess we'll find out soon. And I bet he blames the other guy for being in his way LOL
 
As the Hub Motor Turns and the Lipo Fire Burns. 8/6 - 8/7

I am waiting at least a day to post this to see if I got anybody. I certainly hope so. How many of you guys watched it a second time? Doug installed rear brakes about an hour later. I got the new wheel from Doug. I had to install the 36V controller and throttle also as the 24V throttle is still in the mail.

I took the 80 tooth sprocket off the bent wheel with a hammer and chisel and bolted it on a new freewheel myself. I did not have to remove the new freewheel. I had to butcher the fork with a hacksaw and files to keep it from rubbing though. I did everything except for the brakes. Doug did that. I am progressing.

I see now for myself the poor performance of using a smaller sprocket than is required for the rpm of the motor. I thought at first it was because I was running two motors. I was wrong. I unhooked the back motor and took it around the block. The bike slowed down and the motor got really hot on the flat. I almost burned it out. I had to hook both of them up to get back to Dougs.

I still am not sure if I damaged the motor or not. When it cooled down somewhat I went about a mile after that and barley made it back home. I think the SLAs were low because the motors were warm but not hot. I charged them over night and am taking it for a spin now to see.

The motors seem ok but the front motor gets hotter than the back one. It may be damaged. When the 24V 4 wire throttle comes in I will hook the 24V controller back up and see what difference it will make. If it works than I can run the LIPOs. All I need is some gater clips and I can run the packs in parallel. I am thru with 36V as the SLAs are on their way out. I may never order more SLAs.

I am hoping to get a new MY1020 motor this month. The same motor I had that got broke. 1,000W@48V and 3,000rpm. It will go on the front to replace the current set up. The 20" bike project will then be finished. I will need a 48V controller and a smaller wheel sprocket or larger motor sprocket. I am looking for 30mph.

The Currie will also happen and will be my first gear reduction project. I hope you guys will stay with me. I don’t plan on going anywhere. I may never stop building electric bikes. I want to install a jackshaft below the motor and above the wheel sprocket. It will mount like the MY1020 motor did on the rear rack.

I was told that brushless motors are 5 to 10% faster than a brushed motor of the same power rating due to the better peak efficiency. Based on DAs power graph 1,500W = 35mph. The 1,500 watt 5600rpm brushless motor Skalabala posted should go about 38mph vs the 1,580W AmpFlow motor at 36mph. I don’t want a 36V motor anyway as I can’t run it off my Lipo packs.

I will need a variable 48 - 72V brushless controller for 66.6V or three 6s bricks in series. I can run them for racing and the 44.4V packs I got now for normal usage. Also I was told a brushless motor will perform better than a brushed motor when overvolting it. If that is the case than 40mph could be possible with 66.6V. A 48V brushed motor would most likely burn out. We will find out as I will get a speedometer for all three bikes then.

I have a question about my current motor setup. Both motors are in parallel and hooked to the 36V controller. What would happen if they were in series instead? I know with speakers a parallel connection draws twice the current as a series connection. I don’t know what motors would do though.

Would it help? The current setup does not run well. Motor failure will happen soon if I don’t change something. They seem to be getting too much power and won’t even take half throttle before they stop accelerating. If I hold the wheel off the ground I can engage full throttle and the wheel keeps spinning faster. I know 4200rpm@36V requires a 110 tooth sprocket.

If the answer is yes. Series would help. Then how would they hook up so both motor sprockets spin in the same direction? Please let me know. I may have to run these two motors awhile until I can get another MY1020 motor. Also if the 24V throttle I ordered don’t work with the 24Vcontroller then I can’t run 24V. If it does work how would I wire them at 24V. Parallel or series? Thanks.

LC out.
 
I just noticed that the post DA made right after mandown changed since last night. I read it at Dougs house and it is not the same. I did not know you could change a post after it is posted. Thanks DA. I got a bunch of you guys. :lol: :lol:
 
I am going to go research dual motors in series or parallel now. I still did not get the 24V throttle. Thanks

LC out
 
[quote
Originally posted by goldguy
Parallel..Full volts and 1/2 of the battery capacity to each motor

Series...1/2 the volts and full capacity of the batery to each motor
Sorry goldguy, you got it wrong. It is not possible to get full battery capacity to multiple motors no matter how they are connected. What you meant to say is series is 1/2 voltage to each motor and 1 motor's current requirement. Parallel is same voltage to both motors and twice a motor's required current.


whanderson is offline Find More Posts by whanderson


][/quote]

Thanks dude check out the other videos. If you are still on. I am trying to figure out this series thing. When I lay down to go to sleep last night it came into my head. Will each motor see 18V instead of 36V. I want to go home and try it. I don't really want to unhook the chain though so need to wire the motors so the sprockets are the same the first time or it wont be good at all. Do you have an answer?
 
Seemed fake, so I did a frame by frame.

file.php
 
Sorry dumun ...
You're a day late and a dollar short!

You really should learn to read and figure out what's going on before blurbing in.
Or ... are you vying for the position of LC's comic relief sidekick?
 
latecurtis said:
I took the 80 tooth sprocket off the bent wheel with a hammer and chisel and bolted it on a new freewheel myself. I did not have to remove the new freewheel. I had to butcher the fork with a hacksaw and files to keep it from rubbing though. I did everything except for the brakes. Doug did that. I am progressing.
Good job! - Take a grossly overtaxed component and make it weaker!
latecurtis said:
The motors seem ok but the front motor gets hotter than the back one. It may be damaged. When the 24V 4 wire throttle comes in I will hook the 24V controller back up and see what difference it will make. If it works than I can run the LIPOs. All I need is some gater clips and I can run the packs in parallel. I am thru with 36V as the SLAs are on their way out. I may never order more SLAs.
You want variable speed controller and throttle - single speed controller-contactor will not work with variable speed throttle, might damage it!

Might as well use SLA.
Your typical misuse can destroy Lipo ... same as you are destroying SLA, cheaper to destroy SLA ... till you finally start using as recommended.
latecurtis said:
I was told that brushless motors are 5 to 10% faster than a brushed motor of the same power rating due to the better peak efficiency. Based on DAs power graph 1,500W = 35mph. The 1,500 watt 5600rpm brushless motor Skalabala posted should go about 38mph vs the 1,580W AmpFlow motor at 36mph. I don’t want a 36V motor anyway as I can’t run it off my Lipo packs.
Motors are rated by output watts!
Same watt output = same performance.
Brushless is a few percentage points more efficient, using less the input watts ... but, same watt rating, rpm, gearing etc. = same speed.

36V motor should run just fine at 44.4V ... :?:
latecurtis said:
I have a question about my current motor setup. Both motors are in parallel and hooked to the 36V controller. What would happen if they were in series instead? I know with speakers a parallel connection draws twice the current as a series connection. I don’t know what motors would do though.
~18V to each motor.
Reasonable-moderate speed and much greater efficiency. (usable gearing & less damaging heat)
latecurtis said:
Would it help? The current setup does not run well. Motor failure will happen soon if I don’t change something. They seem to be getting too much power and won’t even take half throttle before they stop accelerating. If I hold the wheel off the ground I can engage full throttle and the wheel keeps spinning faster. I know 4200rpm@36V requires a 110 tooth sprocket.
LC out.
Gearing for high speed greatly amplifies the wasteful damaging heat at less than top speed!
Gearing too high, higher than capable ... reduces speed and performance!
Also kills low speed performance, efficiency, acceleration, motor and batteries!
 
As the Hub Motor Turns and the Lipo Fire Burns.

The series connection works much better. The motors are 2800rpm at 24V. 18V = 2100rpm. With the 80 tooth sprocket they are geared for just under 16mph according to the sprocket calculator on page 71.. I had to reinstall the motors as the sprockets were not lined up properly. It runs better today but is still not perfect. 10mph is about the most it can go without the chain popping off or the front motor getting hot. I will post a video on it as it is the best I can get it now. The back brakes leave much to be desired also. It could be much better.

I don't know if I will be able to afford the 48V MY1020 motor this month. I will need a much better working rear brake when I do get the motor though. Two motors hooked to one sprocket is not as easy as it looks. All three sprockets have to line up perfect. I am close enough now that it will run ok however do not want to take it too far from my house yet. I charged the LIPOs last night and will use the Schwinn for when I need to go farther than 1 mile from home.

Also the good news is if I get a 13 tooth motor sprocket to go with the MY1020 motor at 48V and 1,000W the 80 tooth wheel sprocket will roll the bike at exactly 29mph according to the sprocket calculator. A 15 tooth gears it for 32.5mph which is too much. I will order the 13 tooth when I upgrade to 48V. I will leave the 11 tooth on the motor at 36V. It will go 18mph and should work good up hills. I may not be able to afford anything more this month and when I get the motor wont be able to afford the 48V controller or 13 tooth sprocket until the following month.

I still don't get a government check. I am mostly broke. Temporary assistance gives $225 directly to the landlady and $75 to the electric company. All I get is $44 every two weeks. It may be awhile before I get a $800 government check. When I do though I plan on ordering that brushless motor for the Currie and moving to a first floor apartment or house so I don't have to lug any bikes upstairs. Starting tomorrow I want to research a simple jackshaft gear reduction system for the Currie.

I am going to need a jackshaft gear reduction wheel. Post any links available for the parts if you guys can. I am ready to move on to gear reduction now as that is the next logical step in my progression. I hope you guys will stick around. I know that gear reduction will not be easy. Thanks. Post when you can.

LC out.
 
Rear brake alone gives you about 30% the stopping power of front and rear brakes together.
If precisely done, front brakes alone can be almost as effective as front and rear.
 
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