Nijiflian Bustock
New member
Hi everyone! I'm here to share my experiences with my DIY ebike project. It's been going on for a couple years now. I've had a lot of ups and downs on this journey.
The set up:
Two (recalled) UPP batteries in parallel. 52 volt 20 AH each. 50 amp BMS per pack.
CYC X1 Pro Gen 2 Motor kit with VESC controller.
Amazon full suspension downhill frame. Air suspension front and back.
The story:
It all started when I found a DIY ebike kit from a company called CYC Motors (I'm sure many of you have heard of them at this point). They were having a sale on the X1 Pro Gen 2 kit (it came with an ASI controller) so, I went ahead and bit the bullet. 1000 dollars later I had a kit for my Walmart mountain bike. I started looking at batteries that could power this 5kw beast of a mid drive. After not finding anything powerful enough that still fit in the bike frame I decided I would probably need two batteries. I would mount them on both sides of the frame to keep the weight balanced. I didn't want to spend 2000 more dollars on a pair of 72 volt batteries though so I purchased a pair of 36 volt triangular batteries from a company called Unit Pack Power (UPP). I made a series connector for them and mounted them to the bike frame. I had myself a nice 72 volt 20 amp hour set up that could deliver 40 amps of current to the system.
After riding around for awhile watching the power on the display going up and down i noticed I was only getting around 3kw of power. I did some math (72 x 40) and realized that even with two batteries i couldn't get the power output i wanted. The bike was already really fast but, I wanted more. After saving up some money I started scouring the internet for the best bang for your buck batteries (this time I had a calculator handy). I decided two 52 volt packs in parallel was the way to go. UPP had another triangular battery rated at 52 volts 20 amps hour. It was bigger than the other packs but, it would still mount nicely to the frame. Each battery could deliver a whopping 50 amps. With my new 100 amp limit I went about installing the new batteries on the frame. During my test ride I saw power output as high as 5kw averaging around 4kw on long flat roads during hard acceleration. However, now I had a new problem. Being able to draw so much current was producing enough torque to twist the rear swing arm and popped the chain off. Eventually the drive train had enough of it and the rear sprockets were folded into a nice taco for me to enjoy while I walked the bike home.
The ASI controller that came with the bike bricked itself shortly after that. I contacted CYC. Apparently it was a known issue more than one person was having. I agreed to wait on an in house controller called the X12; a VESC based esc. I decided while I wait to try these VESC controllers myself. They were a tinkerer's dream. Every setting was configurable down to the phase resistance. So I ordered one with the same ratings as the ASI controller. (The X12 controller took over a year to actually finish development and get sent to me. As soon as I got it the hall sensor wires slid right out of the conroller and renered it unusable.)
I started looking at internally geared hubs and a new frame while i waited on the X12 controller. I had picked up a hardtail downhill frame from a local bike shop for cheap. It worked great! However the lack of suspension ended up bothering me. When the internal hub blew up I went direct drive single sprocket. Lacking the torque I loved so much I put the bike up and started more research. I ended up ordering an Enviolo heavy duty CVP hub. If you aren't familiar with it just know that it's an internally geared hub that uses ball bearings as gears and operates like a CVT (continuously variable transmission) in a car.
I found a full suspension frame on Amazon for 800 dollars. I set up everything on the new frame. It was and still is totally awesome. The VESC controllers work great even without hall sensors (CYC controllers must have sensors to work).
I put a lot of miles on this set up. All those miles at 5kw finally caught up to me a couple days ago. While out on a ride the motor finally gave up. The bike is currently in storage while I wait on a new motor. I'm giving the gen 4 motor from CYC a chance as it has better thermal characteristics than the gen 2 had.
So that's where I'm at. I would still recommend the X1 pro kit to anyone willing and able to drop 3 grand on their kit and good enough batteries to power the thing. The motor itself will take quite a beating and I'd be willing to bet it's faster than a Surron at full power.
Here's a picture of the bike as it currently sits (yes thats a hub motor on the back. I was experimenting with driving a hub motor with a mid drive motor. I dont recommend it. It works, but there would need to be a lot more thought put i to what hub motor to use than i put into it. The biggest issue it has is if the mid drive motor has a higher top speed than the hub motor can spin at it turns the hub motor into a brake and sends higher voltage than the pack supplies back into the system. That is very bad). I can't wait to get it running again.
There's also some pictures of my destroyed motor too.
The set up:
Two (recalled) UPP batteries in parallel. 52 volt 20 AH each. 50 amp BMS per pack.
CYC X1 Pro Gen 2 Motor kit with VESC controller.
Amazon full suspension downhill frame. Air suspension front and back.
The story:
It all started when I found a DIY ebike kit from a company called CYC Motors (I'm sure many of you have heard of them at this point). They were having a sale on the X1 Pro Gen 2 kit (it came with an ASI controller) so, I went ahead and bit the bullet. 1000 dollars later I had a kit for my Walmart mountain bike. I started looking at batteries that could power this 5kw beast of a mid drive. After not finding anything powerful enough that still fit in the bike frame I decided I would probably need two batteries. I would mount them on both sides of the frame to keep the weight balanced. I didn't want to spend 2000 more dollars on a pair of 72 volt batteries though so I purchased a pair of 36 volt triangular batteries from a company called Unit Pack Power (UPP). I made a series connector for them and mounted them to the bike frame. I had myself a nice 72 volt 20 amp hour set up that could deliver 40 amps of current to the system.
After riding around for awhile watching the power on the display going up and down i noticed I was only getting around 3kw of power. I did some math (72 x 40) and realized that even with two batteries i couldn't get the power output i wanted. The bike was already really fast but, I wanted more. After saving up some money I started scouring the internet for the best bang for your buck batteries (this time I had a calculator handy). I decided two 52 volt packs in parallel was the way to go. UPP had another triangular battery rated at 52 volts 20 amps hour. It was bigger than the other packs but, it would still mount nicely to the frame. Each battery could deliver a whopping 50 amps. With my new 100 amp limit I went about installing the new batteries on the frame. During my test ride I saw power output as high as 5kw averaging around 4kw on long flat roads during hard acceleration. However, now I had a new problem. Being able to draw so much current was producing enough torque to twist the rear swing arm and popped the chain off. Eventually the drive train had enough of it and the rear sprockets were folded into a nice taco for me to enjoy while I walked the bike home.
The ASI controller that came with the bike bricked itself shortly after that. I contacted CYC. Apparently it was a known issue more than one person was having. I agreed to wait on an in house controller called the X12; a VESC based esc. I decided while I wait to try these VESC controllers myself. They were a tinkerer's dream. Every setting was configurable down to the phase resistance. So I ordered one with the same ratings as the ASI controller. (The X12 controller took over a year to actually finish development and get sent to me. As soon as I got it the hall sensor wires slid right out of the conroller and renered it unusable.)
I started looking at internally geared hubs and a new frame while i waited on the X12 controller. I had picked up a hardtail downhill frame from a local bike shop for cheap. It worked great! However the lack of suspension ended up bothering me. When the internal hub blew up I went direct drive single sprocket. Lacking the torque I loved so much I put the bike up and started more research. I ended up ordering an Enviolo heavy duty CVP hub. If you aren't familiar with it just know that it's an internally geared hub that uses ball bearings as gears and operates like a CVT (continuously variable transmission) in a car.
I found a full suspension frame on Amazon for 800 dollars. I set up everything on the new frame. It was and still is totally awesome. The VESC controllers work great even without hall sensors (CYC controllers must have sensors to work).
I put a lot of miles on this set up. All those miles at 5kw finally caught up to me a couple days ago. While out on a ride the motor finally gave up. The bike is currently in storage while I wait on a new motor. I'm giving the gen 4 motor from CYC a chance as it has better thermal characteristics than the gen 2 had.
So that's where I'm at. I would still recommend the X1 pro kit to anyone willing and able to drop 3 grand on their kit and good enough batteries to power the thing. The motor itself will take quite a beating and I'd be willing to bet it's faster than a Surron at full power.
Here's a picture of the bike as it currently sits (yes thats a hub motor on the back. I was experimenting with driving a hub motor with a mid drive motor. I dont recommend it. It works, but there would need to be a lot more thought put i to what hub motor to use than i put into it. The biggest issue it has is if the mid drive motor has a higher top speed than the hub motor can spin at it turns the hub motor into a brake and sends higher voltage than the pack supplies back into the system. That is very bad). I can't wait to get it running again.
There's also some pictures of my destroyed motor too.