GoldenMotor MP3 install on KHS mountain bike.

jojothedog

1 mW
Joined
Apr 21, 2012
Messages
15
Hi,

This is my first E-bike. I needed something to go to work and back because gas prices are getting ridiculous where I live in Ottawa, Canada. I started to research conversion kits and eventually settled on Golden Motor's Magic Pie 3 from Gary at Goldenmotor.ca. Gary has a reputation of being one of the better ebike dealers as I discovered in my research and I have to agree 100%. He was great to deal with, answered my emails within a day and shipped everything out and I got it within 3 days. I was concerned with torque and hill climbing ability because I have knee issues and should not be peddling and the MP3 was supposed to have good torque for a non-geared hub motor.

Got my kit in and installed it. Spent a night doing it. Takes some effort getting everything just right on the handle bars because of the thumb/finger actuated gear changers I have but I got it all to fit. Had to trim my grips down about an inch but still plenty wide. Everything seems to be of decent quality... time will tell but it all seems solid. The rear wheel was trued really well and fit into my mountain bike frame nicely. It's a very strong robust feeling rim. The wiring loom is all connectors and it made for a clean and easy install as far as wiring goes. A supplied washer and each side of the motor with the 6-speed freewheel I ordered and it all slipped right in and was centered. I had to grind the flanged part of one of the axle nuts because my rear derailleur is so close to the axle. I only have to take it down about 2 millimeters though. Luckily I have a bench grinder that made this easy.

The bolts from my disk brake were too long and touched the aluminum backing of the internal controller and bound the wheel from moving. All I have to do is find shorter ones or grind mine down a few millimeters but I didn't bother and will install it at a later date. I found the regen braking combined with the front brakes felt good anyway but I will definitely install the rear disk at a later point. I am not certain why but the brake lever that was supposed to be the rear brake doesnt engage regen. It might be a controller setting but I can not get the software from their site to install. It's a problem with their install package they are aware of as I have seen other posts about it but they have not corrected the problem. I'll continue to try and get it to install. If anyone knows if getting both levers to start regen is a controller setting let me know please.

I ordered the panier rack that allows the batt pack to slide in and lock on to to prevent theft but I ended up using a rectangular tackle bag I found at Canadian Tire to house the battery. It's perfect for me because the less it looks like an e-bike the better. I don't want to attract unwanted attention and I prefer the stealthy look anyway. At some point I will buy some saddle bags to hang on either side to hide some of the motor as it really catches people's attention. The GM 48v10ah batt pack fits into it easily and there is plenty more room inside for a rain suit and lunch ect. There are zippered pockets on all 4 sides as well. I just tightly bungee it to the rack and it's mounted solidly enough that way. It has a shoulder strap as well which is important because I need to be able to carry this into the office for a charge without everyone seeing a massive battery and charger. So many ignorant people who love to complain about anything and everything.

The cruise control is really nice! I have only gone 16km so far but I already know I would really miss it. Not sure why but having my thumb stretched out to hold the throttle in place is something I can live without. It's just so much more relaxing to set the cruise control and just ride along. I get to 42kmh on flat ground and it pulls my 100kg body up the hills I encounter no problem at around 30kmh. Power and torque wise the motor is everything I imagined. I just need to remember this is not a motorcycle, I have two of them, and that it really doesn't need anymore power for my needs as a commuter bike. I have nothing to compare it to though as this is my first e-bike but I do know that I would not want less torque than I have now. I know there are people who mod or swap controllers to get more amps but I don't really feel the need to do that at all. It does everything I ask of it very well and leaving it alone will ensure better longevity and batt/distance efficiency which is important to me.

So far I am impressed. I'll report back as I spend more time with it.
 
Got another 20km on it today. Decided a little test run to the Tim Horton's and back before I trust it to get me to work and back.

The rack that I ordered from Golden Motor seems kinda flimsy. It's so light that I thought it was aluminum.... unless it is. About 6 km into my ride I heard a noise so I stopped to have a look. The bars that form a V shape down to the axle area were bowing rearwards. This let the pannier bag with batt in it ride lower and lower until it started to rub on the rear wheel. Every time I hit a sewer lid or bump it jolted the pannier rack and it started to buckle under the weight of the battery. Thought I was stuck until I decided to see if I could bend it back enough to get me home... well all it took was the smallest effort with my hand and I bent it back. This stuff is thin and weak. My bad luck I assume because I have not read anyone else having this issue. I drove to Canadian Tire to check out their racks and the one I found weighs 5 times more so I bought it. It feels way way stronger so I will see if that manages to stay straight under the batt's weight and jolts from sharp bumps. If not then it's mounting in the frame time somehow. That or I find a fully suspended bike but that's an expense I'm not really interest in since I have a perfectly good $600 KHS.

I am running narrower street rubber because the knobbies made it like peddling through sand all the time so they translate most of the jolts right though to the frame. Regular fatter softer mountain bike tires would make this less of an issue possibly but I doubt it would eliminate it for me. If I had it to do again I would only convert a fully suspended bike. I might have no choice.

Other than that the motor performed flawlessly for the 8ah I burned and I mostly had it full throttle. Was burning 600w on the flats and 800w-900w on hills. I was averaging 41kmh on flats, 30kmh up some decent hills and going downhill I was reaching 50kmh at times. If I can just settle down and run at 300w which should get me to 30kmh I should get some pretty good distance. But work is only 14 km away so I will just pin it the whole way.
 
Sure, I'll get some pics together. Just gotta borrow a camera. I managed to break mine somehow.

I am thinking for a rear rack I will try one of those ones that attach to the seat post. I think they have some flex in them and will let the rear of the bike hit sharp bumps without jolting the battery pack. As long as it doesn't flop up and down too much it should be good. Of course my plan of running saddle bags won't happen with that style of rack I don't think.

I guess I am used to looking at that plate sized disk in the rear wheel, doesn't look so odd to me. Wow does this thing ever attract attention. I thought it was whisper quiet for the most part but I passed by a concrete wall yesterday and the sound bounced back at me. I thought the wheel had started rubbing on the rear bag again so I stopped to check. People can definitely hear you coming and going with this thing. Don't get me wrong, it's certainly not loud, this being my first e-bike I wrongly assumed brushless & gearless meant no sound or a faint hum. Most everyone that I went by turned to look at me so it certainly makes enough noise to catch everyone's attention. This is on quiet roads though... if there are cars around I doubt anyone can hear me over the traffic.

I'll work on those pics.
 
[ Wow does this thing ever attract attention. I thought it was whisper quiet for the most part but I passed by a concrete wall yesterday and the sound bounced back at me. I thought the wheel had started rubbing on the rear bag again so I stopped to check. People can definitely hear you coming and going with this thing. Don't get me wrong, it's certainly not loud, this being my first e-bike I wrongly assumed brushless & gearless meant no sound or a faint hum. Most everyone that I went by turned to look at me so it certainly makes enough noise to catch everyone's attention. This is on quiet roads though... if there are cars around I doubt anyone can hear me over the traffic.[/quote]


A Brushless, gearless motor should be fairly quiet at a steady speed. If you're fake pedaling the chain/sprocket noise should be audible.
 
Hi Joepah,

No the MP3 is not loud at all. I just want to clarify because I don't want to give it a bad name. I really like this motor and it has been doing everything I ask of it and it had wonderful torque as well. But it is not silent on quiet streets when you are the only thing making noise. It makes just enough hum to get people to turn their heads to see what is making that type of sound, especially if accelerating. The only reason I even mentioned it is because I wrongly assumed it would be silent. It is also the type of sound it makes. It is unusual so people naturally turn to look. Bur it is far from being intrusive... it's actually just a hum.

I am currently trying to find some fatter tires but nobody has them in stock. 26x2.1 is the smallest tire I would buy but no one has them and if they do have that size it's an aggressive knobby. Looks like I will have to order online. Am trying to find a place within Canada so I don't get raped at the border by brokerage firms (that's a great scam they got going there).
 
It's a big motor and the giant cover acts like an acoustic chamber. It's definitely audible in the distance. Many electric bike motors actually are, but the sound of a big DD hub is the loudest.

The MXUS, 9C, golden motor "pro kit" DD are all the same diameter and they are noisy too. But not as noisy as the magic pie.
If you want it to be quiet, travel at a low speed, and pedal along to reduce the motor power consumption.

The MAC/BMC motor has a very shrill tone, but it sounds like a power tool in the distance, and the sound doesn't travel very far. On the bike, it sounds louder, but it is actually less noticeable. I had to put a big bell on my MAC bike to warn pedestrians, they do not hear me coming at all.

If you want quiet, this is not it ;)
But if you want powerful, torquey, and high power handling, reliable.. this is it ;)

I have ran 8kW peak on it before, 2000-2500w continuous... and it lives!!!
 
joepah said:
A Brushless, gearless motor should be fairly quiet at a steady speed. If you're fake pedaling the chain/sprocket noise should be audible.

That's the lie that sales people keep propagating for some reason. All eBike motors put out some sound, some have sound that travels further than others.. The 'pie is one of the least stealth motors out there. It has a high pitch sound that geared motors have, but that giant hub acts like a big acoustic chamber!

[youtube]SoAnGuGAK-s[/youtube]

My gopro picks it up better than any other motor i've played with.
 
Not at all all hub motors.
E+ an Tidial Force motors make ZERO noise even at hard acceleration.
Tidal Force motor is not small diameter also , close to Magic PIE.
Personally I would never got used to sound like in the video on ebike.
Noise of hub motor depends a lot on the method of controlling hub motor, not much on motor itself.
TF and Eplus use electronics designed in USA and manufactured in USA.
 
Sometimes a little noise is a good thing--you don't have to constatly ring your bike bell to get people's attention! When I get the shopping cart with the noisey wheel at the store, then I don't have to excuse myself so often because people can hear that I'm just about to run into them when I get to a blind intersection. Of course, there is a lot to be said for that serene sunset cruise when you just want to hear nature and the rustle of wind past your ears (or through your helmet if you like to cruise above10 mph).
 
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