Hub replacement

Bicycle hub, rim and spokes on a newspaper, ready for assembly

This poor wheel has seen a litany of mechanicals in its two-and-a-half-year life, and it’s all my fault. The trouble started several hundred kilometers into an ill-starred Lejog ride, when the rear derailleur got stuck in the four lowest cogs. In my haste to get the gears shifting again, I backed out the limit screws. There’s a reason I shouldn’t have done it, and sure enough, an hour or so later I ended up putting the chain into the spokes. The result was several broken and mangled spokes, and some galling of the hub flange. I’m still grateful to Ben the Amazing Wandering Bicycle Mechanic for showing up late in the evening with a truck full of tools and getting me back on the road.

Mechanic truing wheel on bike in parking lot
Ben’s mobile bike repair

Since that seminal mechanical, the following ignoble history of broken spokes has plagued the wheel:

That was the spoke that broke the camel’s back. After checking prices for a replacement hub and all 32 28 spokes, I bought a new rear wheel (and, incidentally, new tires). The new wheel and tires are working fine and I’m very pleased with the result.

But that rim with its broken spoke has remained sitting on the balcony, where I can see it every morning through the bedroom window. I kept looking at it, and the spare front wheel (the one with the dynamo hub that I bought for Lejog) and thinking how neat it would be to have a spare set of wheels. Just for … reasons. And so (even though it doesn’t make economic sense), I finally ordered a replacement hub and spokes. (Yes, and nipples.)

Step 1: Disassembly

Bicycle wheel on newspaper-covered floor
Wheel beginning

I realized I had to remove the rim tape first in order to remove the nipples. The tape put up more of a fight than I expected. That’s a good thing, because the tape has one job and it’s sticking to it!

Bicycle wheel with discarded rim tape and cutter on newspaper-covered floor
The rim tape put up a fight

To prevent the nipples from falling inside the rim as I removed them, I used my time-honored technique of threading a spare spoke in through the opposite end.

Montage showing the use of a spare spoke to remove nipples from a bicycle wheel
A spare spoke is an invaluable tool

I started with the drive side and removed all the nipples first. When I’d created some space, I started pulling out loose spokes.

Bicycle wheel with removed spokes and nipples on newspaper-covered floor
Making progress on the drive side

Some clown got the spoke wrench on crooked when he replaced a broken spoke a while back. The nipple was rounded off, and subsequent efforts to remove it with a pair of pliers resulted in a broken nipple! I saved this spoke for last, and then pushed it through the rim until I could get at the hex head on the nipple with the pliers. It took some work but I finally removed it.

Bicycle rim and hub with single spoke and broken nipple
Monkey with a spoke wrench

And with that, the disassembly is done. I kept the bits for the drive side (which I’d previously replaced) separate from the non-drive side (which are original), and I sequestered the broken nipple and corresponding spoke.

Parts for a bicycle wheel, including rim, hub, spokes and nipples, as well as gloves and tools
Bicycle wheel (some assembly required)

I still need to clean the old latex and tape residue off the rim before the rebuilding starts.

Bicycle rim with dried latex and tape residue
Some gunk remains

With all the spokes removed, the damage to the hub flange from the earlier spoke breakage is evident.

Bicycle hub showing damaged flange
Not supposed to be shiny

I haven’t decided yet what to do with the hub. I can reuse the freewheel body, and possibly the bearings. It will be a challenge to find some use for the remaining naked hub — it’s the wrong shape to make a novelty drink coaster.

Damaged bicycle hub on newspaper
This ol’ hub

Step 2: Reassembly

Nearly a month has passed since I disassembled the wheel. The hub, spokes and nipples arrived from Germany, but the package was torn and some nipples were missing. I’d ordered 30 (to have a couple of spares) and received 19. It took a week to get a response from the vendor, but they finally asked if I could get the replacement nipples locally, and they’d refund me the difference. I could and did — 100 nipples, in fact, with next-day delivery. I told the vendor of course they didn’t have to pay for 100, and they ended up refunding me 5 euros.

I got the replacement nipples on Jan. 26, and since then I’ve just been waiting for the right opportunity to get started.

Bicycle hub, rim and spokes on a newspaper, ready for assembly
Taking stock

A friend asked what the difference was between a wheel with 28 spokes and one with 32, and of course the answer is four spokes. Anyway, it’s a trade-off between strength and weight. His question made me curious enough to see what difference four spokes and nipples would make.

Four spokes and nipples on a scale
Answer: not a lot

That hardly seems worth the difference, especially when you consider that an extra four holes in the rim and hub will mean the difference is even less.

Before starting I had a brief refresher, particularly on the significance of the key spoke:

With that under my belt, I quickly set to work.

Hand holding a bicycle hub with a few spokes inserted
Key spoke at top right

Partially assembled bicycle wheel on a newspaper
The first seven

Bicycle rim held on edge to view the hub logo through the valve hole
Hub logo through the valve hole — the mark of a pro

The work proceeded quickly after that. I’d ordered slightly thicker spokes and laced them cross three (each spoke crosses three others between the hub and rim), rather than the original cross two, for extra strength. But once I got all the spokes in place, it was clear I’d made a miscalculation: the spokes were too long.

Bicycle wheel before spokes are tightened
Sam, you made the spokes too long

I could recalculate the spoke length and order new spokes, or I could try cross four (even stronger!) and see if the length worked out. Either way, I had to tear down the wheel again and start over.

Bicycle wheel disassembled
Back to the drawing board

I decided to give cross four a try. It was a fight to get the spokes in the right position without tangling their heads together in the hub flange, but I got there in the end.

Wheel newly laced before spokes are tightened
That’s more like it

Newly assembled wheel with tightened spokes
After 10 minutes with a spoke key

The final step in building a wheel is truing it. This is a repetitive process of tightening the spokes, checking the roundness of the wheel and the position of the rim between the hub ends, and checking the spoke tension. It is far more art than science (although I’ve seen videos of high-speed machines with high-tech measuring tools at a factory), and it helps to stop every so often and stress the spokes manually to get them to seat in. But we got there in the end.

Tight and true

Along the way, the monkey reappeared and rounded off another nipple. I’m happy to say it was easier this time to get the damaged nipple off, and I was able to replace it without having to disassemble the wheel yet again.

A pristine bicycle nipple next to a damaged one
Before and after monkey

With the wheel tight and true, I topped off the reassembly with fresh rim tape and a new valve.

Montage of bicycle wheel in truing stand
Taped and valved

Another day

The wheel is ready now for a brake disc, cassette and tire. I’m saving those steps for another day as it’s dark and cold out on the Workshop in the Sky, and it might be a bit of a fight to get the tubeless tire to mount. As this wheel is meant for a spare anyway, there’s no hurry.

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