Kenny LövrinUpdatesAbout
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Short Life of Trouble

Custom chopper with electric drivetrain

one-off · ongoing since 2023

I’ve always enjoyed building things and trying out the ideas I have. Building a custom motorcycle had been on that list for a long time, and since I like to do things a little differently where I can, this one is electric.

Essentially all the brackets that hold the motor, battery and controller are my own designs, which I had laser cut and bent. I had help with the welding and the machining.

I’ve put a timeline of visual notes below, in case you want to see the build step by step. It isn’t a complete list of every step and change, but it gives a picture of the whole process.

If you have any questions, feel free to get in touch with me.

The build
The charge port cap fitted in the tank, seen from the side
July 14, 2026

Designed and printed a cover for the contactor for a cleaner look and added safety.

The filler opening on the tank with the charge lead coming out of it
July 13, 2026

Updated version of the gas cap emergency stop. Opted for a lanyard style, which works surprisingly well aesthetically.

The battery box with the main cables run and terminated
July 12, 2026

The contactor is properly connected now. It will make sure that high voltage is mechanically disconnected when ignition is off or the emergency stop is triggered.

The painted tank on a blanket, its filler cap fittedThe terminals under the tank that the mounting has to clear
July 11, 2026

Got my contactor mounting bracket design back. 3D printed a prototype tank cap emergency stop. Test fitted it all.

The tank fitted above the battery box, charge lead running up into it
July 7, 2026

Emergency stop wasn’t good enough, need to add a proper contactor and switch.

The whole bike on the garage floor, wiring done and battery in
June 22, 2026

I think the bike is complete now.

The same loom from further back, wires fanned out to each sideThe fuse block seen straight down, terminals numbered
June 21, 2026

Designed and printed a bracket to fit all the cables to. Routed and strapped down properly.

The bike from the side with the battery box back in place
June 18, 2026

Everything connected and working, routed properly to the tank. Now need to clean up under the tank.

A handful of new wires held against the wall
June 12, 2026

Turns out that it was trickier to get the speedo to talk to the motor controller than expected. Had to make my own signal converter.

The headlight lit in the dark garage, tools spread on the floor
April 28, 2026

It took a long time to get going again, but working on the last parts of the 12V system. Got lights working properly again.

The bike further along, standing on its wheels in the garage
January 20, 2026

Back at it, managed to get the BMS replaced and got the drive train up and running again.

The painted bike part-assembled, battery box back in the frame
August 10, 2025

Almost got all the way, unfortunately I destroyed the BMS by accident.

The painted frame back in the garage with its wheels and forks refitted
July 27, 2025

Back to a rolling chassis.

The bare frame propped up in the garage, ready to go away
July 22, 2025

The basic structure is back together now.

The frame stripped bare on the garage floor, every part removed
July 18, 2025

Got the painted parts back. Color is a Porsche Crayon light gray.

The bike standing at the edge of a rapeseed field in bloom
May 20, 2025

The bike is feature complete, may have done a short test run. Time for disassembly.

The front wheel and fender, seen from the side outdoorsThe chain guard mounted above the chain, seen from the drive side
May 17, 2025

Mounted my custom designed chain guard. Laser cut and bent aluminum.

The bike outside on the gravel, seen from the side
May 11, 2025

Charging setup verified and working.

The charge port fitted in the frame, with the chain and motor behind it
May 10, 2025

Charge port properly fitted with updated back cover design.

The updated front sprocket guard fitted over the drive, chain running below
May 7, 2025

Fitted my updated sprocket guard design. 3D printed aluminum.

The rear wheel and drive side with the new wiring run along the frameThe high-voltage components laid out in a case on the bench
May 4, 2025

Replaced the charger cables with my own angled cable routes and thinner cabling. Charger in place, updated controller box cover.

The bike on the lift with its wiring pulled out and laid over the frame
May 2, 2025

Worked on 12V system, most of it verified working.

The rear of the bike in the garage with the taillight litThe headlight lit, seen from beside the front wheel
April 26, 2025

Mounted my plate and light holder and wired up the lights to verify function.

A rule held against the electronics to measure the spaceThe chain and motor with a printed front sprocket guard fitted
April 13, 2025

Tested a badly printed prototype for a front sprocket guard design. Also tested a rough prototype for a controller box cover.

The charge port in its housing, wires attached, on the bench
April 9, 2025

Replaced the plastic tube and grommet with my own custom cup and cables for easier routing and cleaner look.

The finned cover fitted over the motor on the drive side
March 8, 2025

Verified that my cut and bent charge port bracket design actually fits.

The top clamp and fork tubes at the steering headThe front wheel and fork leg, seen from the side
February 15, 2025

Custom indicator light mounts, doubling as triple tree clamp bolts.

The upholstered seat, diamond stitched, standing on the floor
February 13, 2025

Got the completed seat back.

The battery box closed, sitting on a workbenchThe battery box opened, showing the pack and its plate inside
January 16, 2025

Replaced the stock cover of the charger with my custom design, making it possible to mount below the seat.

The headlight shell on the bench with its loom hanging out
January 12, 2025

Had the bottom of the tank cut out, using it as a mounting bracket for all 12V electronics.

The bike under a white sheet beside the garage door
December 7, 2024

Got a Sportster tank to hide electronics.

The seat, covered in black leather, packed in a box
December 1, 2024

Painted the underside of the seat before I send it off for upholstering.

The bike pushed into the corner of the garage
November 26, 2024

Got extra material added to the seatpan to better be able to add some mounting threads.

The bike from the side with the finished seat pan mountedThe seat pan resting on a stool beside the bike
November 1, 2024

Got the laser cut seatpan. Using an IKEA bench to create the radius for the fender fit.

The grip and brake lever on the handlebarThe master cylinder and lever on the handlebar
October 26, 2024

Replaced the grip clamps with versions containing a push button.

The whole bike standing in the garage
October 22, 2024

The fundamentals are in place. The bike is mechanically ridable now.

The bike with the primed fender and seat base fitted
September 25, 2024

Made an initial paper reference for a custom seatpan that I could bring into the CAD software.

Looking straight down the forks from in front of the bike
September 18, 2024

Brake lines and brake light switches in place.

A floorboard bracket hung off the frame railThe floorboard folded down against the garage floor
September 2, 2024

Designed and got foot peg mounts in place. Simplest solution I could come up with.

The handlebars fitted, seen from aboveThe bars with the controls mounted, seen from the front
September 1, 2024

Bars on, got the internal electric throttle mounted. Also got the brake levers in place.

The sissy bar and fender seen from behind the rear tireThe rear fender shaped over the tire, seen from behind
August 24, 2024

Figured out the sissy bar and fender mount combo.

The rolling chassis standing in the garage, forks and battery fitted
August 23, 2024

Starting to look like a bike with the basics in place.

The rear wheel and brake, seen from behind the frame
August 21, 2024

Rear bracket is shaped and fixed with an adjustable rod.

The rear caliper bolted to its mount beside the disc
June 16, 2024

Got help milling the Sportster caliper bracket to a more uniform size for this positioning. First rough version.

The rear disc and its carrier, seen from the drive side
June 5, 2024

Figuring out spacing for fender and positioning of the rear brake caliper.

The rear wheel in the frame, seen from behindA fender held over the rear tire to judge the line
May 2, 2024

Test fitted the rear fender. Got it too narrow, will change for the same but wider model.

The front brake disc and caliper on the wheel
April 28, 2024

Mounted the front Sportster caliper, fits as expected.

The rolling chassis standing on the garage floor
April 20, 2024

Got tires onto the rims, complete wheels now.

The rolling chassis on the floor, forks and both wheels fittedA close view of the battery box and its mounting bracket
March 28, 2024

Got the side and top brackets to hold the battery in place. They also allow a place to mount the controller.

The motor on its finished plate, seen from the drive side
March 14, 2024

Got the motor mounted on the new bracket, much better.

The machined motor plate bolted into the frame
March 13, 2024

Tried a better idea for mounting the motor and making a space to rest the battery. Much sturdier.

A pair of fork legs standing against the frame on the lift
March 9, 2024

Found a complete used Sportster triple tree and fork legs. The lower legs in quite bad shape.

The frame up on a lift with the battery box on the floor beside itThe battery box hung in the frame, seen from the drive side
December 20, 2023

Got and mocked up the first idea of a box to hold the battery and mount the controller.

The throttle and its cable on the benchThe charger on a stool beside the workbench
November 27, 2023

Verified the basic functionality and wiring of battery, motor and controller combo.

The frame on its wheels with the controller box standing beside it
November 21, 2023

Received the battery pack, here just on the table in front of the frame. The best mock up I could do at the time.

The motor's drive sprocket lined up with the rear sprocket behind itThe rear sprocket bolted to the wheel hub, seen from below
October 26, 2023

Got a rear sprocket to better verify that the chain alignment will actually work.

The motor with its cover fitted, mounted in the frameThe motor on its mount, seen from the drive side
October 24, 2023

Received the laser cut and bent motor mounts for test fitting.

Sighting down the frame from behind, past the rear tire
October 14, 2023

Using the simplest method I could think of for centering the rear wheel with spacers.

The rear wheel in the frame beside the motor
October 12, 2023

Got a rear wheel as it is important when referencing sprocket alignment and motor positioning.

The motor blocked up on timber inside the frame
October 9, 2023

Second attempt at motor brackets, here using one in front and one on the back.

The motor and its drive sprocket held up against the frame
October 4, 2023

Trying out some initial ideas for motor brackets, 3D-printing prototypes.

The bare frame on a table, the motor set into it loosely
September 28, 2023

Got the Kraftech Sportster frame, motor and controller. First basic mock up to start thinking about the motor mount brackets.