Brompton P Line Gear-Shifting Trouble: How I Diagnosed and Fixed It

Daily · Published 10/10/2022 ·

One of the two Brompton P Line bikes I shipped out from Gwangju started having a gear-shifting problem.

The Problem

The Brompton P Line — the rear rack, mid-bar model — wouldn’t let me use 1st or 2nd gear.

My first thought was that something was off with the tension on the cable that pulls the rear derailleur, the part that decides where the chain sits.

When I ran through the gears, it was clear where the trouble was. The catch was, I had no idea how to actually fix it.

What Was Happening

The cable tension had gone off — stretched out, I think, though I couldn’t tell you exactly why — and I could barely get it to shift into 3rd or 4th.

For a bike where I lean on 1st and 2nd gear constantly, this was a serious issue.

My Approach

I went after the cable tension first. Over at the shifter end, I pulled out the cable and turned it to bring back a little more tension.

At first both 1st and 2nd dropped right in, and I thought, ah, problem solved.

Following the cable along, I spotted another spot where you can dial out a bit of slack — down at the bottom of the derailleur cable, it looked like you could turn it to adjust.

One of us held the bike and kept turning the pedals, while the other turned the cable, tweaking it until 2nd, and then 1st, finally caught.

It Came Back

Just when I thought I’d more or less fixed it, the problem returned.

It was clear I needed a professional’s hands on this. I called around a few places, but getting even basic service done turned out to be tough.

So I dropped by a nearby shop, and they told me it can’t be fully fixed right now — the part for that section isn’t available in the country. With the P Line, they said, you can basically assume there’s almost no parts stock yet.

The mechanic did a temporary fix to get me by. It rides fine for now, so I’ll keep riding it for a good while, and once the problem flares up again I’ll just replace the part first and carry on.

Wrapping Up

Every moving part breaks eventually. The only difference is when and how often, because they all wear down. Bikes especially aren’t built to lock in some rock-solid, bombproof setting — they’re built light.

So you have to ride them while making little adjustments along the way. No need to stress over the occasional hiccup. They’re supposed to break.

When something breaks, you fix it and keep riding — that’s all there is to it. It varies from person to person, and honestly I’m someone who loves having everything in perfect condition all the time, but bit by bit I’m coming to accept reality and let it go.

Wishing you all timely tune-ups and safe rides.

#BromptonPLine #Brompton #브롬튼 #BoughtItMyself

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