Anyone have any experience with the new Magic Pie 4?

[Ghausler]

Hi all

I am a new member and new to the ebike scene.  I have been researching g for several months and I believe that, despite the many problems reported in earlier years, golden motors has the best value for the buck and seems to have improved their quality control.  I would like to do my first build using their new Magic Pie 4 conversion kit, but don't want to be on the "bleeding edge" all alone.  So my question is, has anyone had experiece good or bad with this kit?

[Bikemad]

I am currently using an MP4 kit on my home-made chopper bike (A.K.A. the wheelie machine):



The MP4 is a very good motor and the new vector controller makes it incredibly quiet to use.
The motor is not 100% silent, but it isn't any noisier than riding with the battery turned off!

The MPIII becomes quite noisy under heavy load due to the "pinging" noise produced by the stator. The vector controller does not cause the pinging noise so the motor makes the same noise relative to wheel speed on full throttle as it does with the throttle released. If you pedal enough to prevent the freewheel from clicking, the total lack of additional motor noise when the throttle is applied is quite impressive.

The torque on the MP4 is very impressive too, so much so that I had to reduce the acceleration setting to allow the front wheel to remain in contact with the ground every time I pull away from a standstill (especially on an up-hill incline). On my front mounted Smart Pie 4, I also had to reduce the acceleration setting, but that was to stop the front wheel from spinning while pulling away on loose gravel and wet road surfaces.

I also have the BAC-601 Smart Display and pedelec sensor unit fitted to the wheelie machine and they both seem to work extremely well with the MP4:





The pedal assistance is automatically turned off when level "0" is selected, but when needed, you can select an assistance level of anywhere between 1 and 5 by simply pressing the up or down buttons. Although with my current power settings as high as they are, the wheelie machine can be quite dangerous to use at slow speed on setting 3 and above. If I start to pedal a little bit too hard, the front wheel lifts up very quickly. Although I instinctively stop pedalling immediately, the slight delay in the pedelec power cut off means that the wheel just keeps on lifting, and if I don't grab the brake levers quick enough it will actually flip me over backwards. But to be fair, this would not happen on a more conventional bike:



I tried lifting the rear wheel off the ground and gave it full throttle, and I was surprised to find out exactly how high the unloaded speed of the motor is on a 48V battery pack:



So, if you were hurtling down a steep hill at full throttle, it would just be the wind resistance holding you back, as the motor itself would not produce any drag until you began to exceed 35mph. 

The only negative experience I had with the MP4 was trying to figure out how to program the controller, but having discovered the correct procedure for connecting to the software it is now very straightforward.

I have six GM motors, and apart from the offset rim and badly fitted spokes on the first Magic Pie, and blowing up a couple of modified internal controllers, I can honestly say that I am very happy with all the GM products that I have used, and especially the MP4.

Alan
 

[GM Canada]

I'm a little late to the party on this post, but after over 1000 miles on the MP4 I can honestly say it has surpassed all my expectations. Lots of silent smooth power. Without revealing any numbers I can say I have sold a lot of these kits. The reliability has also surpassed my expectations. Issues are rare. If any issues arise it is usually something odd has happened to create a problem. Out of the box these kits just work great!



Gary

[Kauaikit]

Yes…I'll have to agree with both Gary and Alan, especially with the ease of installment and the lower cost for my first complete GM MP4 "kit" installed. These latest MP4 hub/kits work as designed. I'm too sold on the sine wave controller being used on the MP4.

My personal goal is to see a MP4 match the performance and silence of my Tidalforce ebikes, which is 31.5mph/50.4kph (195lbs) on level ground. The specs for the TF is a peak 1950 watts/58.8amps.

So Gary or Alan, any info, for increase speed/performance, on a maybe MP5 upgrade from Golden Motor in the works?   

[Marsbar]

I just got the MP4 but I think there is something wrong with it.

How long does it take before you give "full power" on the throttle before then engine kicks in?

After breaking mine takes 7-10 seconds before it kicks in.

Do you know if there is any difference on running the software on Windows 8 instead of Windows 7?

[Supchrgamx]

mine does the same thing with a fully charged 48v battery and my regen is turned up to high
almost like the regen has nowhere to go and screws up the controller for a bit
for me I ride for 5-10 min and then it stops doing it , so I don't break hard for the first bit and then it becomes better than mp3
just my thoughts

Laurence

[Bikemad]

How long does it take before you give "full power" on the throttle before then engine kicks in?

When the acceleration is set at 100% it should be almost instant, but if you use the wrong software and reprogram the controller the acceleration setting will not go above 5% (even if 100% has been entered and accepted) because you cannot increase the acceleration setting above 5% using old vector software on a newer vector controller.

The old software only allowed 5 different values of 1, 2, 3, 4 or 5 to be stored as the acceleration parameter and these equate to 20%, 40%, 60%, 80% and 100%.
The later controller and software allows 101 values of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, etc. right up to 100 (or presumably the hexadecimal equivalent) to be stored as the acceleration parameter and these directly equate to 0 - 100%.
If you use the old software, it stores 100% as a value of 5, but the later controllers will interpret a value of 5 to be 5% not 100%.

Do you know if there is any difference on running the software on Windows 8 instead of Windows 7?

It might be worth trying to run the software in compatibility mode using an earlier version of windows if Windows 8 will allow it.
Try right clicking on the program icon and see what compatibility options are available.

mine does the same thing with a fully charged 48v battery and my regen is turned up to high
almost like the regen has nowhere to go and screws up the controller for a bit
for me I ride for 5-10 min and then it stops doing it , so I don't break hard for the first bit and then it becomes better than mp3

Laurence, do you know if your overvoltage protection value is set to 62V on your controller?

Alan
 

[Marsbar]

Well, sorry to say but sending back the MP4 tomorrow. I have no way of fault finding. I had enough trouble with my MP2 before I discovered a pin was faulty on the USB cable. I hope they will send me a MP III as replacement. Have asked for MP2 rear internal controller, but I am afraid this is out of production.

For the electrical braking, this worked well actually and saves the brakes. Unfortunately the motor would sleep for 10 secounds before it would kick in again and assist me after each braking.

On the positive side, MP4 was strong once it got going, no sound at all. Also, rim this time was accurate and well done, no issues there.

I think Golden Motor was on the right track with MP2 internal controller. Programming software works, nice cable system also with exposed wires at the end so you could use a multimetre to measure signals or cable. Controller was protected inside, and wires soldered directly on the board. Plug was nice ans solid.

In my opinion all plugs should be avoided and cables connected in a JB, that also can contain the key switch for on/off. Plugs will sooner or later be broken and there will be water ingress. (I use whit vaseline inside all plugs to avoid corrosion and water ingress)

When I turned the throttle on my MP2 there was no delay and I knew exactly what I got. With MP4 the delay causes me to have the throttle either on or off with no regulation.

The saying "keep it simple stupid" greatly applies. So, hoping GM will give a refund or send a MP III soon.

Have to survive using my old bike meanwhile...

[Supchrgamx]

it was set at 62 changed it to 65
to me it felt like the back side of regen ramp is a bit sluggish
the longer that you hold the brake the  longer you wait
got around it by doing short break pulses
that got annoying
so I disconnected rear brake regen and ran it on front brake only
that was my work around solution

Laurence

[Marsbar]

Same as I experienced. Counted 7 seconds before the motor would respond after a brake. 7 seconds is a long time in the cycling world.

Drove me nuts, because if you want to get around you brake and accelerate continuously. Often I start to press the brake in slightly because I know I am going to brake. So the electrical brake is not for me, but I could wire it so that the brake handles shuts off the motor.

Still I had the programming issue.

Oh well, a new product allways take time to remove errors. No wonder I have a 30 year old car with carburettor 

[Supchrgamx]

the other solution maybe is and I have not tried this, is to reduce the regen  amount
I did not have time to try it before 2 feet of snow arrived 
if the regen current is less maybe the ramp time would be less
all I know is the wife was bitching that her mp3  could not do the stuff I was doing on the vector
they will sort it out im sure

Laurence

[Haggan]

Bikermad. What kind of Light are you having on the wheelie machine
And the extra Light and horn switches is that GM standard or where can I get one of them?

[Bikemad]

The "Wheelie Machine" is basically a work in progress fun bike which is currently being used for testing the pedelec function of the MP4 controlled by the BAC-601 Smart Display unit.



The front light in the above photo is a 240V 10W led floodlight, although it seems to run very well off a 48V battery.
Unfortunately, the very widespread light means it can only be used as a main beam or headlamp flash for road use as it would be extremely hazardous to oncoming traffic in the dark.

I plan on installing a DC-DC converter to provide a 12V supply directly to the LED from an eight cell 29.6V LiPo battery pack which I mainly use more often than the bigger 48V pack.

The additional switch is available from Gary (GM Canada):



But I will be replacing the existing on/off rocker switch for a three position rocker switch to operate the indicators:



Alan
 

[Haggan]

Hej
Aha cool. So it is to bright so it will blind car driver?

How did you connect the three button switch? Soldering on the cables. Or is there any GM spare contacts you can buy to create custom ones?

I have hydralic brakes on my bike so I got a Manget switch. And I destroyed the brake I got with the kit. and solderd the wires. A better solution would to create a new end with GM brake contact. But I have not seen any spares.

cheers

[Bikemad]

I could probably get away with using it as a daylight running light during the day as it is not focused enough to blind car drivers, but it would definitely be too bright to use with oncoming traffic at night, but if the drivers don't dip their headlamps on unlit roads, I would be very tempted to try it out!

The wires need to be soldered, but I do not have this switch connected to the Pie's harness.
The light switch and the horn button are connected in parallel to allow the front light to be turned on and off, or I can just use the horn button to intermittently flash the headlamp for signalling if required.

I also have a well focused 3W LED light bolted to the frame (with a built in inverter accepting 12-80V input voltage):



I have it angled downwards so as not to dazzle oncoming traffic and originally connected it to the lighting feed and ground wires on the MP4 wiring harness. Unfortunately the 85mA current draw from the LED was sufficient to cause a significant voltage drop on the thin wires supplying the battery feed to the LED battery gauge (causing the three LEDs to dim slightly) as well as a corresponding voltage rise on the thin ground wire, this unfortunately caused the motor to run without touching the throttle when the light was turned on.

Until I get chance to wire everything up properly, I have simply disconnected the LED light and just use this bike during the day when it is still light enough to not require lights.

Alan