Motor was cutting in and out, broken brake cutoff wire.

Jason Knight

Well-Known Member
Keene, NH
Got a bit of a surprise on my last ride where the motor was cutting in and out willy nilly. Turns out the sensor on the zoom brakes my Aventure came with had it's wire worn clear through the housing! Thankfully disconnecting the cable was simple since they put push-together connectors at the bars, and with it disabled I was able to resume my ride.

This bike isn't old enough, nor has it been knocked around enough for a failure like this:


When I first got the bike the rear brakes didn't work, so Aventon sent me the full kit though all I needed was a rear caliper, so I have spare parts. I figured "fine, I'll just swap the sensor for the one from the spare rear kit". The failure was for the front brakes, but I figured the sensor was the same. Luckily -- or sadly -- enough they are the same.

In getting it out of the brake handle I discovered a second issue. Can anyone out there see it? It's plain as day!

Completely stripped. At first I thought I botched it or there was something wrong with it... but in pulling the sensors from both the broken and the replacement they were equally screwed up. To say there's thread left on the retaining bolt is delusional.

So out came my measuring caliper and the hole and what's left of the threads are a mismatch for the bloody bolt! This zoom brand is shoving them in there any-old-way not caring if the threads even match! Great choice of vendor there Aventon.

Since there's no thread left on either of them, I ended up adding a small bead of epoxy and just using a adjustable wrench loose over the end with a rubber mallet to drive it in.

The original failure though isn't too much of a surprise because coming out of the retaining bolt there's nothing even remotely resembling a strain relief. Thankfully I've got electrical connectors galore so I'm gonna search through my bin for some wire "wrap-on" reliefs that I guess i'll just epoxy to the bolt. Got some old '70's 1/8th inch plugs who's reliefs should do the trick.

*SIGH* the joys of maintaining a bicycle. While I'm in there the hose for the front is now barely long enough to go from the handle to the caliper in a straight line after my fork swap. I think I'll swap the hose from the spare rear kit onto the front. Saves me ordering more parts I guess.
Glad you were able to figure it out and come up with a solution. Congrats to being back on the road!
None of my existing junk fits, so I ordered some wrap-on strain reliefs off Amazon.

I went to the LBS (who I don't entirely trust) for something simple, and took a look around at the e-bikes they had. NONE of them seem to put proper strain reliefs on ... well... anything.

I mean I could see it for things like bike cables, they're tough, they can take it... but for anything electrical or for things like hydraulic brake lines... Delta Alpha Foxtrot Uniform Quebec!

Even the cheapest audio and USB cables at least PRETEND to have strain reliefs molded in. Is this indeed common practice to just let the cable sit there any-old-way with next to zero reinforcement?

In web development we have the phrase "Don't let back-end developers write the front-end." IS this basically the same thing where "don't let bike builders do electronics?"