I've been running an e-bike conversion shop since 2019. The most expensive lesson of my career came on a Tuesday morning in June 2023, when a delivery rider walked in with a cargo bike, chain grease on his hands, and one clear request: he wanted a Bafang 1000W hub motor kit.
"I've got cargo, I've got hills," he said. "I don't have time for a weak system."
I knew the product well. The Bafang rear hub motor kit had been my go-to for conversions for years. The kits I usually spec for cargo are direct-drive, meaning fewer moving parts. No nylon gears to shred, no planetary reduction to service. Bolt it in, connect the controller, and it just runs. That dependability made me comfortable. Too comfortable, apparently.
The Mistake That Cost $3,400
The bike was an aluminum cargo frame with standard 135mm dropouts. The kit bolted in clean. The wiring followed the diagram exactly. I set the controller to a reasonable current limit. Everything looked right.
Then I did something stupid. I skipped the torque arm.
For anyone who hasn't installed a hub motor before: a torque arm spreads the motor's reaction torque from the axle to the frame. Without it, the motor axle can spin in the dropout. On a steel frame, you might just get some scratches. On aluminum, the axle chews the dropout slot into an oval, and eventually the whole thing lets go. A torque arm is a simple steel bracket that costs about as much as a modest lunch. It does exactly one job, and it does it perfectly. I decided that saving 30 minutes was worth more than that. It wasn't.
I knew this. I'd actually written "torque arm required" on other customers' invoices. But this time, I looked at the heavy frame and told myself the weight alone would hold the axle in place. I convinced myself that a Bafang motor at this power level didn't really need the extra hardware.
Two weeks later, the rider called me, and I could hear the panic in his voice. The rear wheel had locked up mid-ride. He was okay — but the frame was not. The axle had twisted, shredded the aluminum dropout, and turned what used to be a cargo bike into scrap.
People assume the motor failed. It didn't. The motor was absolutely fine. My installation was the problem. I paid for the replacement frame out of pocket, and the rider missed a week of deliveries on top of that. The worst part wasn't the money, though. It was telling him the frame was done. He didn't get angry, which honestly made it worse. He just said, "I thought you knew what you were doing."
How I Ended Up Researching Inline Gear Reducers
While I waited for the replacement frame, I did what I should have done before ordering any kit. I researched how torque loads actually work in different drive configurations.
Here's what I found. A direct-drive hub motor pushes all of its torque straight to the axle. That's why the torque arm is non-negotiable. A geared hub motor uses a planetary reduction inside the shell, which changes the torque path. And some builders don't use a hub motor at all — they use a separate inline gear reducer bolted to a motor shaft.
An inline gear reducer is basically a gearbox mounted inline with the motor. The motor spins fast with low torque, and the reducer converts that into low-speed, high-torque output. You'll see them in conveyor drives, industrial gates, packaging machinery, and DIY electric vehicles. A friend of mine built an electric trike for hauling tools around a warehouse. He used a small DC motor, an inline gear reducer with a 10:1 ratio, and a chain to the rear axle. It's slow and heavy, but it'll drag half a ton without complaining. You can't get that kind of torque from a hub motor alone.
They're not a beginner-friendly option, either. You have to figure out shaft alignment, keyways, mounting brackets, chain and sprocket sizes. But for a specific job, they beat the alternative — running an oversized motor at partial throttle — by a wide margin.
That shifted how I approach every motor request now. The right question isn't "which motor is best?" It's "which configuration fits the load and the use case?" A hub motor is fine for a regular commuter. For very low-speed, high-torque jobs, an inline gear reducer or a mid-drive motor is the better answer.
The Search That Led Me to 5th Gear Motors and Pete Jackson Gear Drives
Around that time, a supplier's rep told me his company had started carrying 5th Gear Motors, a smaller manufacturer offering electric motors and gearboxes, including inline reducers. I hadn't heard of them, so I asked my mechanic, who's been in this industry since the 1990s. He grunted and said, "If you're going down the gear drive path, you should look up Pete Jackson."
So I Googled exactly what he told me: "what happened to Pete Jackson gear drives?"
Turns out, Pete Jackson Gear Drives was a California company that made gear-driven timing sets for hot rod engines back in the 60s and 70s. Instead of a timing chain, you ran a set of gears directly between the crankshaft and camshaft. Racers loved how solid they felt, but they were loud. A gear drive whines in a way that's satisfying on a race track and annoying on a street car.
Then the market changed. Timing chains got much better. Engines got quieter. Fuel injection and electronic engine control changed the whole vibration and noise profile of performance cars. Demand for aftermarket gear drives dried up, and the brand faded away.
But the name still shows up in forums. People who picked up an old crate motor or a barn-find project car keep asking whether they can still source a Pete Jackson gear drive, or whether they should just convert back to a timing chain. The general consensus: convert back to a chain unless you're building a race car and want the sound.
I'm not going to pretend the forums all agree on the exact history — they don't. The pattern, though, is pretty clear.
What This Whole Mess Taught Me
I reinstalled the replacement frame with a fresh Bafang rear hub motor kit and, this time, two proper torque arms. That bike is still running today, more than 4,000 km later (note to self: never again without a torque arm).
The whole experience changed my pre-install checklist:
- Torque arm on every hub motor install. No exceptions. Frame material and motor power don't change the physics.
- Measure the dropout width, axle diameter, and frame type before ordering a kit, not after.
- Ask about load, hills, and target speed before recommending a motor. A 1000W direct-drive hub motor is great for speed. If a customer needs crawling torque, a geared hub motor or a mid-drive is the right call.
- For non-bike projects, consider an inline gear reducer as a legitimate alternative to a giant motor.
And one more thing about Bafang motors specifically: they are not the lightest, quietest, or most elegant systems out there. If you're building a boutique e-MTB and every gram matters, you might be better off with another brand. But for working riders who need a motor that runs, can be repaired, and has parts and documentation that won't disappear next year, Bafang is a genuinely solid choice.
That's the exact opposite of the Pete Jackson story. The products that survive aren't the loudest or the flashiest. They're the ones you can still get parts for in a decade.
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