2022_05_21_bike_spokes.md 4.7KB
title: Blog post: Bicycle Repair description: Replacing broken rear wheel spokes date: 2022-05-21
comments: true
Driving back home from work on Thursday I suddenly heard a strange noise and felt a wobbly sensation on my bike. Taking a closer look, it turns out two spokes in the rear wheel have broken.
Over at the Toolbox Markdorf we have a bike repair stand and a wheel centering stand, as well as other bike-related tools. So I drove over there to do the repairs.
On the gear shift side, a small plastic disc prevents the spokes being taken out. It can simply be pulled off and put back on afterwards.
Removing the brake disc requires a special tool by Shimano, called the “Lock Ring Tool TL-LR10”. Fortunately I already bought that when I rebuilt my wheel.
Here you can see the two broken spokes, next to six unused ones I still had left over, because my rim only needs 32 spokes.
Normally I would have centered and tensioned the rim and spokes myself, but unfortunately Philipp borrowed the Spoke Tension Meter from the Toolbox Bike Workshop, and I was not able to reach him on short notice 😉
But then I remembered that I saw a small local bike workshop in Markdorf, Fahrrad Hienerwadel. So I quickly went over there and brought my prepared rim, only needing to center and tension the rims. The shop owner was able to do the job quickly on-the-spot, in less than 20min with 15€ having been exchanged, I was on my way back to the Toolbox.
He did a good job centering the wheel. I put the tube and tire back on and pumped it up, using an old emergency compressor from a Mercedes I salvaged, fed by a 3S Quadcopter LiPo.
Back home, I just had to put the wheel back in the bike frame. Now it’s good to go again!
As I mentioned above, I already completely re-built my rear wheel with new spokes a while ago, in September 2020. The tools for this were ordered by the Toolbox and are now available there, namely: repair stand, centering stand, tension meter and spoke wrench.
Here are the verbatim notes I made back there, with some specs of my bike and wheel, as well as some useful links if you want to rebuild your wheel as well.
Centurion e-Fire 408 Tour (??)
https://marktplatz.bike/CENTURION-E-Fire%20Tour%20408%20%7C%20Modelljahr%202017
Schaltung:
Shimano Alfine SG-S7000- 8
https://newwheel.net/questions/pages/viewpage.action?pageId=57671795
https://bike.shimano.com/en-EU/product/component/alfine-s7000s700/SG-S7000-8.html
Muttern: Rechts Blau, Links Gruen
Felge Laufrad:
Alexrims MPD-14, 36 L. (??)
28″ / 622
ETRTO 40-622
32 Speichen, 3-fach gekreuzt
Original Speichen: 1.2mm Durchmesser
Ersatz Speichen von Werkstatt: 2mm Durchmesser
Passende Spannung fuer Stahlspeichen mit Toolbox Messgeraet:
ca. 22 bis 24 (oder 21 bis 25)
https://www.sheldonbrown.com/wheelbuild.html
http://www.fa-technik.adfc.de/Werkstatt/Einspeichen/index.html
http://www.kreuzotter.de/deutsch/speich.htm
Durchmesser des Kreises durch die Speichenenden D = 600 mm
Durchmesser des Nabenflansch-Lochkreises d = 92.6 mm
Abstand Flansch - Mittelebene a = 28.65 mm
Anzahl Speichenkreuzungen k = 3
Speichen-Anzahl n = 32
Speichenlänge = 286.0 mm
286mm ist die korrekte Laenge!
Even though I heard bad things I have to say rebuilding a wheel is not that hard. Just read through some tutorials on the web or watch some YouTube videos on the topic and try it yourself!