I bought my Z125 Pro with 80 miles on the clock in late 2017. It stayed completely stock until recently, which would not have made for a very exciting build thread. Recently, I decided it uses way too much gas and I had to do something about it (that was a joke). So I decided to go electric! Since I no longer have any CC's and I only kind of know what I'm doing, I'll call this bike the Z000 Amateur. Here is my 10 step build plan:
Totally stock Z (except the bar end mirrors). This was actually the day I put it on Craigslist, thinking I would sell this bike and use the money toward a different electric motorcycle. Whereís the fun in that?! After only getting contacted by scammers, I decided to take matters into my own hands and modify the Z.
Step 1: Spend a bunch of money on parts
Next step was motor and battery selection. I went with a 72V 70Ah lithium battery (20S20P of 18650 cells), an 8kW QS hub motor, and a Kelly KSL-7275H controller. We could debate the merits and drawbacks of hub motors but this is not a large motorcycle as you know, so I went with something that packages really well and leaves room for batteries.
Step 2: Take out the engine!
The engine and rear wheel are no longer required so I took those out and sold them. I love how easy this bike is to work on and I had the engine out all by myself in only a few hours.
I sold parts on eBay to help recovery some costs of the motor and battery.
If youíre gonna follow this build thread, get used to bad pictures in a dark garage lol. Itís a shared garage for the building and the landlord has the lights come on at night on a timer. That means it is always dark.
Step 3: Mock up battery box
At this point you should have tons of Amazon boxes of all different sizes from the junk youíve bought to support this project. Cut one up and use it to test fit your battery box.
Now you can see why I went with the hub motor Ė leaving the entire engine area wide open leaves room for a decent size battery.
I wanted to go with an aluminum battery box. Since Iím not a good welder I plan to trap the battery between two plates separated by spacers, with closeouts around the outsides. I modeled it up in CAD to create a file for cutting the plates.
Step 4: Motor testing!
Unfortunately I didnít take any great pictures of this setup. Maybe thatís for the best so you donít have to see how messy my bedroom is. I had the wheel/motor on my rear stand and then a ratís nest of wires between components. This was to make sure I can get the motor running smoothly and responding to throttle input before I bring it all downstairs to the garage.
Worked through a few issues, but all the hardware appears to be in good shape! There is some shoddy wiring here somewhat attributed to the Chinese battery manufacturer but some my own doing. That will get fixed up once everything gets installed on the bike. For now, itís good news that I can talked to the motor controller and make it do what I want.
Step 5a: Install fender delete kit
Believe me, this step is super important. It has nothing to do with the electric conversion but the stock fended just looks bad. I canít believe I left it there so long
Step 5b: (More) disassembly
I still had a bunch of gas guzzling parts on the Z that needed removal. If you thought it looked stripped down beforeÖ
I took off the grips (since Iím going to an electric throttle), fuel system, tank, clutch lever and associated hoses and wires. Now weíre at bare bones.
Extra fuel was donated to my Triumph which will happy drink it up this week.
Iím not too sure what to do with the tank. It obviously isnít required anymore, but I think the bike will look bad without it. Possibly will cut out the bottom and use for storage or keep a charger in there. Open to suggestions from yall.
[TODO] Step 6: Component mockup
Test fit everything to see how it mounts up. This also drives the wire length and routing
[TODO] Step 7: Paint battery box plates (black, ofc) and tidy up wiring off bike
[TODO] Step 8: Component final install and wiring on bike
Now that everything is pretty and fits the way it should, time to install it on the bike.
[TODO] Step 9: Wire up speedometer
This gets a step to itself since Iím not exactly sure how this works yet. Also, the turn signals (and who knows what else) run through the speedometer so Iím not sure how to keep them working with the new electric speedo. Hit me up with ideas!
[TODO] Step 10: Ride!