Should You Jet Wash Your Bike? | Maintenance Monday
Why Bicycles Stack Exchange recommends it
Bicycles Stack Exchange answerers and commenters link it as evidence that pressure washers and driving rain rarely force water past sealed bearings.
Recommended by 0 people across 0 different months, 2017 to 2024.
What it is
A Global Cycling Network Maintenance Monday episode in which presenter Simon tests whether a pressure washer can damage a sealed bottom bracket bearing. He blasts the bearing directly with a jet wash to see how easily water gets past the seals.
What people said
Cites Rider_X · 2017-06 · Bicycles Stack Exchange · on “Will driving through heavy rain with bike on my car damage the bike?”
The prevalent thought among many members of the Cycling Illuminati (trademark) is that the high vehicle speeds will drive rain into your bearings on a bike if it is mounted to the roof rack. Seems kinda plausible, but here is a GCN video about how hard it is to actually drive water past seals and into bearings with a pressure washer: Should You Jet Wash Your Bike? [this video] Spoiler: It took them a long time, with the pressure washer jet focused directly on the bearing itself at point blank for 3+ minutes to finally drive some water past the seals. Unless you are traveling down the Autobahn [LINK] at top speed with your bike mounted to a roof rack you hyper-car, you will probably be just fine.
Cites David Richerby · 2018-02 · Bicycles Stack Exchange · on “How to secure a fully carbon (aero) bike when washing/repairing on a stand?”
@JamesPeterMcConnell GCN did a test [this video] and found it's actually pretty difficult to get water into bearings with a pressure washer. Their test wasn't entirely realistic but they didn't get any water in a bottom bracket bearing after pressure washing it for a minute and a half at close range. But your concern is completely rational.
Cites Weiwen Ng · 2024-04 · Bicycles Stack Exchange · on “FSA Mega Exo 24 threaded shell BB turns free when off the bike, but turns rough and gritty once installed”
I asked in comments if the bearing felt notchy when you turned it off the bike. You indicated in an update that this was true. Consider all the physical aspects of the bottom bracket: how wide the BB shell is, how round the bore is, how off-center are the bores on each side (I think this is more a carbon bike thing), how flat are the edges of the shell, how far apart are the edges of the shell, etc. Each of these will have a nominal dimension, e.g. a standard British BB shell for road bikes should be 68mm wide. If you took very accurate calipers and measured the actual shell widths of a sample of bikes, most likely no bike would be 68.00000mm. There will be some variance. Tolerance is the am