A box bike without a wheel is just a box

We moved to a new home in November of 2022 and, due to my misfortune, the front motor hub of my Bakfiets died a WEEK before we planned to move. The wheel would spin but with lots of resistance and the motor wouldn’t work. So even pedalling was not feasible.

Talk about bad timing.

Context about our new home:

We renovated it over much of 2022 and I did almost all of the work myself on my spare time. There was a clear cost benefit for this approach, but it took a lot of energy and time (which took away from our opportunities to go hiking) and we needed to move in November on time due to several reasons. We also had a water leak from our upstairs neighbors right as I was finishing up, so that had to be dealt with with the strata, remediation companies and insurance and put me far behind schedule.

So in that last week before moving, I was trying to tie up loose ends – trash runs, hardware store runs, lots of running to and from the property. Throughout the renovation I used the Bakfiets for everything (hardware store runs for small stuff to lumber and drywall compound, taking trash out) and rode it hard that year. It was really inconvenient to lose the Bakfiets right before moving and was incredibly stressful.

I called around and struggled to find anyone who would repair it. Most reputable bike shops will only repair something they installed. This is an old Grin retrofit installed by a bike shop (from what I could tell on the stickers on the bike) that no longer exists.

I didn’t have time to repair it right away. We had to move. So we did that. Then all of the usual tasks after moving and renovating: unpacking, finishing up the renovation (paint touch ups, installing backsplash, building some remaining shelves, etc).

So during that time I transitioned to taking the bus – which is now reasonably convenient to get to/from daycare from our new place.

After a month or two I had time to figure out what the issue likely was – and while it probably was the gears in the hub, I realized that’s a bit of work and this was an opportunity for me to fix a number of other issues:

  • Poorly mounted controller that moves around and gets bumped by our bike lock /chain easily
  • Lots of wires that kids – including my own – pull on. Hazards of parking at the daycare downtown.
  • I have had to repair the power cables in spots due to chafing when we bought the bike.
  • Poor, non water proof connections that corrode or lose connection sometimes. I had been cleaning the connection several times in the winter months to avoid losing power to the motor.
  • The first gen Cycle Analyst had broken a while back so I had to remove it. It’s nice to have to monitor battery life, speed and power output.
  • The front wheel spokes needed tru’ing. I had to tighten the spokes in 2022 by quite a lot and got it *pretty good* but still need to spend a lot of time dialing it in. I’m not well practiced with this, so it takes me longer than it should.
  • The front wheel has torque backlash when I apply the throttle.
  • Toothless is growing, and getting heavier. I have been using the bike for heavy hauls. I’d like to future proof it to make sure it’s capable of carrying heavier loads
  • The front wheel tire valve hole has been drilled out from a presta valve to Schrader. I have been using presta tubes due to local supply options. While presta is a bit hard to fit the pump with the large front motor hub, it still fits.
  • The controller model is unknown and, while I figured out the motor model and brand I couldn’t find any info on the controller. This makes it difficult to expand or add to the system.

I’m sure there are a bunch of other issues or concerns, but these are my primary ones I’m hoping to address. Each of these individually are easy enough to address but together it adds up to a lot of labour and a bit of cost if I DIY. If I manage to get a bike shop to repair it, the labour itself would cost more than parts for a new system.

So, I ran a few numbers and decided to just get a new ready to roll kit from Grin and install it myself. Doing that costs me more than individual repairs if I DIY, but it hits all of the individual issues I listed above with significantly less labour so I can get the Bakfiets on the road sooner. I can then look at slowly repairing the old motor and controller over time and either sell them or use them on our new Bike Friday Hauladay.

  • The new controller mounts in my battery cradle
    • This makes the controller more secure, and keeps it out of the way of the lock and chain
    • This helps tidy up the wires so they aren’t at risk of being moved around
    • Fewer wire bundles will help prevent chafing and fewer connections with this set up helps prevent poor connections due to both corrosion and tension
  • The new controller is known and I can add/remove to the system
    • This wasn’t an issue, but this new kit allows for me to install a pedal cadence sensor. I have one included in the kit and will install it after the bike is on the road (requires modifications to the crank arm).
  • The new motor comes laced to a wheel.
    • Wheel is true and tight
    • Wheel is unmodified
  • The new motor is more powerful than the old one.
  • The kit comes with a backlash / torque arm bracket. This will help keep everything on the front end tight
  • The wires in the kit contain waterproof connectors, in particular the one that connects to the motor (the key one that I have been having issues with on our current configuration). Some connectors are not waterproof but for those the wires are routed further away from the bottom bracket or not routed under the box (less water intrusion) and the connectors are small enough that they can be secured and sealed with heat shrink to minimize water intrusion.
  • The kit comes with a new Cycle Analyst

I ordered the kit a few weeks ago and received it before the Easter long weekend. We had plans over the weekend so I haven’t been able to start work on the bike until this week. Let’s hope it comes together.

Here are the new parts:

Controller, Cycle Analyst, Pedal Cadence sensor, Heat Sink, Torque Arm
I didn’t take a photo of the wheel as I received it so here is a photo after I mounted the tire

Now to install it all!

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