I bought an used Super73 Z1 about a year ago ($700 - great deal). It was clear immediately that the 36V system was not going to cut it - not enough power, and not nearly enough range. Thankfully, Rick Cordero (RunPlayBack) put together a phenomenal ‘how to’ video on upgrading the Z1 to 48V system (https://www.youtube.com/watch?v=o6SQyMFBmyc). So, within a few weeks, I gutted my Z1, installed the KT Controller/Display, and a 48V 15Ah battery from Brick Lithium. I also ended up adding a parallel EM3EV battery for more range. I rode that setup all last year, with mostly no issues. However, on hard rides and hot days, the KT controller would cut out from overheating. The KT controller was mounted inside the battery tray, with very little (if any) air cooling, so that's most likely the reason why.
Fast forward to this year, I decided to make some upgrades to the bike; to hopefully address the overheat/cutout issues, and just have a higher performing bike. Since Grintech’s Phaserunners are out of stock (for who knows how long), I opted to go with the Grintech Baserunner. I have not seen any Super73 / Baserunner build threads yet (here or elsewhere), so I figured I’d take ya’ll along for the ride (and probably crowd source some help where needed)….
First off - a pic of the bike. Basic black Z1 with the turquoise seat.

I removed the seat and battery tray from the bike, as well as the KT controller and display. Below is the battery tray, completely gutted, with the exception of the battery.
As a means of theft prevention, I designed and printed an AirTag holder. Simple design that mounts with 2 rivets.
The AirTag holder mounted inside the battery tray.
After the AirTag was installed, I drilled and installed (with rivets) a few wiring standoffs. These will provide wire retention later in the build.
Since the previous controller was over heating (most likely due to lack of cooling), I decided to design and print a custom vent (hood scoop).
On the underside of the hood scoop, I glued a piece of window screen. My intent was to try and prevent larger debris inadvertently getting into the battery tray. Also, I added double sided tape around the periphery, to help with attachment, but also act like a gasket. Overall, I’m pretty happy with how it turned out, but won’t know how effective it is until I get the bike up and running.
To install the hood scoop, I had to drill 8 holes in the battery tray. The hood scoop was attached with ( qty 8 ) M3 fasteners, washers, and nylon lock nuts.
View of the inside of the battery tray with the hood scoop installed.
Fast forward to this year, I decided to make some upgrades to the bike; to hopefully address the overheat/cutout issues, and just have a higher performing bike. Since Grintech’s Phaserunners are out of stock (for who knows how long), I opted to go with the Grintech Baserunner. I have not seen any Super73 / Baserunner build threads yet (here or elsewhere), so I figured I’d take ya’ll along for the ride (and probably crowd source some help where needed)….
First off - a pic of the bike. Basic black Z1 with the turquoise seat.

I removed the seat and battery tray from the bike, as well as the KT controller and display. Below is the battery tray, completely gutted, with the exception of the battery.
As a means of theft prevention, I designed and printed an AirTag holder. Simple design that mounts with 2 rivets.
The AirTag holder mounted inside the battery tray.
After the AirTag was installed, I drilled and installed (with rivets) a few wiring standoffs. These will provide wire retention later in the build.
Since the previous controller was over heating (most likely due to lack of cooling), I decided to design and print a custom vent (hood scoop).
On the underside of the hood scoop, I glued a piece of window screen. My intent was to try and prevent larger debris inadvertently getting into the battery tray. Also, I added double sided tape around the periphery, to help with attachment, but also act like a gasket. Overall, I’m pretty happy with how it turned out, but won’t know how effective it is until I get the bike up and running.
To install the hood scoop, I had to drill 8 holes in the battery tray. The hood scoop was attached with ( qty 8 ) M3 fasteners, washers, and nylon lock nuts.
View of the inside of the battery tray with the hood scoop installed.