GoldenMotor.com Forum
General Category => Magic Pie & Smart Pie Discussions => Topic started by: Andrew on December 02, 2010, 09:06:46 PM
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swapping Magic Pie motor with internal controller and 48v battery for a 48v GM 1000w HBS motor
What parts in total would be needed to do this?
1. external controller
2. HBS motor and wheel
3?
4?
What new cables would be needed? and would it be a straight forward swap over
Andrew :)
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1- 48v1000w motor and wheel
1- external controller
That sounds about right. All the plugs from your current controls will just plug directly into the wiring harness of the external controller. Sounds simple enough.
Now my question is why?
Gary
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Why? Always a good question!
Well the first thing I should ask is what are the main performance differences between the two motors?
I'm happy with the PIE, but i'm curious about the 1000w HBS. Such as,
1. will the HBS wind quicker?
2. have quicker take-off?
3. Will it have similar top speed?
4. Will it be quieter?
5. Lighter?
6. Will range be more,less or the same? (GM 48v/12ah)
7. Hill climbing?
8. Will I lose any functions that are on the PIE?
ideally i'd like a quieter, more discreet motor, that has quicker take-off than my PIE.
Andrew :)
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Hey Andrew
You should get a front pie instead and some earmuffs :D
hehe
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i'm not sure i'd have the balls to ride two pies, sounds like an accident waiting to happen :D
I PIED to work today and the temperature was about -8c. I ride pretty hard, take no prisoners and get in every cars way :). ..........But two Pies? No way - HARDCORE!! :D
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Hi Andrew.
Take offs are somewhat limited by your choice of wheel size and or 6 fets controllers.
Source out a 12 or 18 fets job and you may see a difference on both HBS and MP.
I need to do more inductance testing on a removed stator of the Pie. Something is weird about it. This weirdness has great potential to exploit or to take away some performance. when I get this 12 fet controller up and running on the Pie I will let you know if my suspicions as to the weirdness are correct.
I havent tried that cap mod on the release pulse to cruise control as I just figured it should work and took the week off. SOZ
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no worries les, i'm about to add a larger front outer chainring(48 tooth) and a 7 speed freewheel with an 11 tooth cog which has been as hard to find as rocking horse sh;t. This will help me keep up with the PIE when it's at full speed. I plan on fitting hydraulic brakes very soon, but there will be a fair bit of cable relocation on the bike. I've also got rid of the front de-railer and gear shifter and am planning on putting a left hand twist shifter to operate the rear gears on the freewheel as I find it hard to change gear on the right side when controlling the throttle at the same time.
As for regen, I will have it relocated to a button and I will see how I get on
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Why? Always a good question!
Well the first thing I should ask is what are the main performance differences between the two motors?
I'm happy with the PIE, but i'm curious about the 1000w HBS. Such as,
1. will the HBS wind quicker?
2. have quicker take-off?
3. Will it have similar top speed?
4. Will it be quieter?
5. Lighter?
6. Will range be more,less or the same? (GM 48v/12ah)
7. Hill climbing?
8. Will I lose any functions that are on the PIE?
ideally i'd like a quieter, more discreet motor, that has quicker take-off than my PIE.
Andrew :)
Sheesh so many questions.. I'll go with..
No
Yes
faster
yes
yes
less
worse
No
Gary :D
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I've also got rid of the front de-railer and gear shifter and am planning on putting a left hand twist shifter to operate the rear gears on the freewheel as I find it hard to change gear on the right side when controlling the throttle at the same time.
Or you could do as I did. My bike is only a six speed with no front derailor. I moved the thumb throttle to the left side. It took a very short time to get used to and I didnt have to buy anything else to accomidate the twist shift on the right.
Gary
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Hey Andrew
You should get a front pie instead and some earmuffs :D
hehe
lol...
Very funny, but true! A second pie solved any issues I was having, now its all WooHoo and YeeHaw!
Gary
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Hey true that Gary
Increase in take off, accelerates on hill climbs and increase in range who cares what it sounds like!!
I don't think I could go back... Plus the weight distribution is so much better. The kits should come in a pair standard lol
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I've also got rid of the front de-railer and gear shifter and am planning on putting a left hand twist shifter to operate the rear gears on the freewheel as I find it hard to change gear on the right side when controlling the throttle at the same time.
Or you could do as I did. My bike is only a six speed with no front derailor. I moved the thumb throttle to the left side. It took a very short time to get used to and I didnt have to buy anything else to accomidate the twist shift on the right.
Gary
Gary, thanks for answering my questions above. As for the twist shift, I will put it on the left side (upside down) i'll just have to twist 'up' to go up a gear. That's the plan away., but knowing me i've forgotten something obvious.
Monkey,.... my pie slows right down on hills and eventually dies :-\
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The initial current during take off for the Pie with the MC seems to be limited.
Like if I pull the throttle on hard I read the CA and Im lucky to pull 5 amps holding the bike at a stand still.
When testing the inductance of the Pie it came short of the HBS.
Side by side comparison MP to HBS is once the MP gets a little RPM happening the current shoots up very high into the good hill climbing ability category.
If you want the Pie to take off like a rocket, a small wheel diameter allows the RPM to go higher at the initial take offs.
Another fast solutions is to get 12 fet controller mod it to do 60 amps max and double the MAX amps by using two packs.
Some of those infineon controllers can easily do 40 amps at 72v 2880 watts, at 48v 60 amps is still 288o watts so this works well.
A big fat C rate pack and current into the 60 amp mark will certainly get the bike going off the mark.
The efficiency could possible be regained with a lower continuous setting.
At ES they are suggesting a 2.5 phase current to 1 pack current ratio is good. 60A max 24A cont.
The MC can do 50 amps max without a hitch if you open up the shunt path and good cooling.
A lot of heat can get up over the controller shunt and feed it to the fets, again, I think the meager 20 amp shunt is evil. The software is fine to manage the currents so to control more current into the controller.
Problem we are having is the GM controller is designed for the GM BMS. When we add another shunt with a CA standalone even though its a 100 amp max shunt. it still adds ohms to a circuit.
Othe BMS's may have a shunt in them too.
By the time the current gets to you motor its been through three resistors. Software management starts to lose its accuracy when all these shunts are already doing the AMP limitation.
Ha Im almost tempted to bridge my shunt full closed and just use the Ping BMS shunt and use the software to control the whole thing.
The software does work if you give the controller something to work with.
That daid if you want a pocket rocket go for a P string of cells or better still a dual pack.
Choice Dual Pack vs Dual Pie. I would go for the second pack in a heart beat.
You can get the second Pie after you get the second pack up and running.
The dual Pie I see now why it is good. It will double the torque in this take off moment the MP is at its weakest. You don't need the second pack just a second Pie.
However the second pack gets you better range and better life span if you desire to Push your motor/s to the max.
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Monkey,.... my pie slows right down on hills and eventually dies :-\
Something is wrong wrong wrong. My 26" belts up the hills. Vooom.
I must do a video of a 26" MP ride at its serious best. 50 amps and off road..
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Some hills near me are quite steep, but I have also felt the motor struggling on very slow slightly ascending inclines. I tought above all else that the PIE's main benefit would be hill climbing. top speed was not important to me.
I suppose that's why I'm curious to try a 1000w HBS
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I would go out now and video the pie's performance but the streets by me are covered in black ice, it's like a skating rink. If it thaws out, I will try later. I have a mini dv thumb size camera I can cable tie to the handle bars ;D
it's a bit like this near me at present..... http://www.youtube.com/watch?v=zMzeiMJQrvk
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OMG. Its like watching destruction derby in slomo, glad no one was hurt.
Wouldnt you think they would give the car a miss and find some tire chains.
Warm your pack up wif some 15 min on off balance charging before you ride if you think its too cold. Just a theory of mine that a normal temp batt works better than a cold battery and balance charging can get the temperature up inside the cell faster.
And leave the charger on over very cold nights and have the pack inside..
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Some hills near me are quite steep, but I have also felt the motor struggling on very slow slightly ascending inclines. I tought above all else that the PIE's main benefit would be hill climbing. top speed was not important to me.
I suppose that's why I'm curious to try a 1000w HBS
I feel your pain Andrew - my pie is slow up hills too
To the point that it will slow down until it comes to a complete stop.
I got a watt meter from here http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=10777
$29 USD (and it's in Germany which means no tax for you)
Just to see for myself how powerful this thing is.
My instinct says that the controller is just sh!t and it doesn't do the pie any justice.
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hi Magzy ;D. glad you've finally got your pie on the road. I'm happy with my pie as it still allows me to use my bike as a bike (just), but I am a little dismayed by the performance purely because what is advertised by GM. As you say, the pie dies on hills even though it was designed as a larger 'torquier' motor to supersede the 1000w HBS. So why restrict it so much with the magic controller and why put on programmable adjustable paramenters when they obviously cannot be used and make no difference. It is as if the whole product once manufactured did not deliver what it was meant to and GM was stuck with a big bill and lots of pies with dodgy controllers and gimic software that just didn't work as it was designed to do. why hasn't there been a torque figure put out on the pie in comparison to the HBS motors as here......
http://www.goldenmotor.com/magicpie/compare.html (http://www.goldenmotor.com/magicpie/compare.html)
I may get a 1000w HBS with external magic controller and do a back to back test ;D
This is not really a moan, but just speculation and comments on my experience on the performance of the pie, and with all this said, the GM pie kit is still a lot cheaper than equivalent kits out there.
Andrew :)
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Personally, with the Magic pie, I was longing for an e-bike with great acceleration and stealthy noise. but I've got a children's toy that makes a lot of noise.
I agree I so wish I'd spent my money on something else now.
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Hey dudes
lol not poking any sticks guys! I'm a curious Monkey :D
Andrew - what's going on with the software? When you say it makes no difference at all, what kind of things is it doing/not doing? When you make the 24v setting, have you left it and gone for a ride? :D I'm surprised to hear that theres no difference. You must be an unhappy chappy.. I'm curious what's going on there.
Magzy - hey man did you get some readings on the Turnigy? Forgive my rudeness hehe, but how much does you + your bike weigh? And about acceleration, if you really want some juice on take off you need to get some more amps into the controller by modding it, or getting an infineon or something. Or check all of your power cables to see if they are minimum 12AWG (10AWG is ideal) you could get a noticeable difference there alone.
My GM battery has 12AWG going to the BMS, then 14AWG to the case Anderson connector. The first 2 GM power cables I have was 10AWG, and was DIY solder. The second 2 GM power cables I have were pre-soldered and 16AWG.... tisk tisk.... Haha I put that down to people complaining about the cables not pre-soldered lol
Using the 10AWG cable is far better, and since I have replaced the power cable inside the GM pack with 10AWG and also fitted a rear anderson connector hehe, All the cables are 10AWG now to minimise voltage drop.
I really don't know how quiet you want something to be, but anything over 500W is going to be loud - in your ears I think... I have a pedal scooter that is near silent, only a teeny tiny groan on take off, but only 32km/h top speed. It's 48v 500W, decent acceleration and will accelerate uphil to near 25km/h. Fun to ride but not for tracks...
The bigger wheel you go, the less torque + more load you are going to have for a given power level.
My best and easiest mod so far I'm most happy with, is adding the front MP. Just slap the front wheel on, couple of wires and shazaam you're away meep meep
Anywho I hope something comes up that solves your worries... peace out
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Monkey, I'm not unhappy with the pie, infact if it was any faster or more powerful it would completely eliminate the light exercise that I actually want from my e-bike. I just feel a bit done over by claims made by GM and other distributors on the pies performance as well as the magic controllers limitations compared to what's claimed, makes you wonder if the battery itself is what it should be.
As for changes in voltage with programming, i've tried riding at 48v for a few days, then 24 for a few, and then back again, and there is no difference - Honestly! I know the software works as I have changed regen power and can feel big differences in the motor braking.
I probably should not expect too much from an electric motor, and i'm happy with 22 -24 mph on flat road. But feeling the motor dieing/losing momentum on slight inclines is a little disappointing as speed reduces quickly and before you know it you are doing 6 mph
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hmmm I can see your frustration... and don't know what to say lol
Going up those hills must feel like the battery is dying... Do you think you could try a thicker battery cable to your wheel? Both of my newer wheels came with pretty slim gauge and I only noticed the biggest difference changing it with dual drive. If you have a multimeter see if you can check the voltage drop when you put the wheel under load, if it is significant and your battery is full charge then I would look to increase the battery to wheel wire thickness, or look at monitoring the output of the battery you are using. It may not be the wheel at all if the battery cannot pump out the juice..
If you do have a few hills, or the hills are big/long then I would still look at getting a front motor because you would most likely get better range too plus never having to worry about going 6mph uphill hehe