Pondering this today driving home from a ride. Luckily I have a van and don’t jetwash. Some people don’t jetwash to protect bearings etc but then drive home in the driving rain with the bike on the roof. Surely the headset etc is taking a battering from the the rain, and maybe even the BB? Just musing and wonder if it at all really matters.

It doesn’t matter. 🙂

I suspect the water pressure, or velocity, or something else from physics, might not be as much when driving through rain.

Put your hand out of the car window when it’s raining and see how it feels.
Then give yourself a quick blast in the hand with a jet wash for comparison.

I jet wash my bike at least 3 times a week in the winter months,my jetwash is one of favorite bits of winter kit as it makes a laborious,tough and time consuming job quick and easy helps keep me riding.

The velocity of water from a jet washer is a couple or few hundred miles per hour, and focused into small droplets so when they hit a surface it is a large amount of energy concentrated on a small area – enough to do damage to car tyre sidewalls apparently. Rain is relatively large droplets at 70mph. No problem.

Jetwash your bike and the muck all comes off. Drive down the motorway for half hour in the rain with the bike on top and it’s still dirty.

Tells you everything you need to know!

Rain is relatively large droplets at 70mph. No problem.

At 150mph it gets clean.. you lot just have slow cars

I had wet bikes freeze on the roof before now, couldn’t turn the steering, pedals etc. Had to put them in the shower room to defrost.

I don’t jetwash the bike nor do I put it on the roof or even outside of the car. Both for the same reason, why ay £££ for a bike and then subject it to high pressure water/grime/grit/air at 70mph.

(Note if you put your hand a few feet from the nozzle of a jetwash it’s not travelling at 200mph, more like the 70 or lower on the car but I would still do neither)

As I posted before I’d sooner out the family on the roof than the bike 🙂

sharkattack, dynebaruk – both spot on there !

Don’t jet wash your hand. Some jet washes can penetrate the skin especially at close range. Can be a very nasty injury.

Can be a very nasty injury deadly.

Its a mountain bike. If it can’t stand a bit of grime, grit and dirt then it’s not much of a mountain bike. People spend many more thousands of pounds on a car (well most people do) which sits out on the drive through all weathers and withstands grit, grime and dirt. 70mph is not very fast really.

I heard a story from a shop mechanic about a chap who kept having to get his BB and frame bearings replaced very frequently. Shop kept asking “Are you jetwashing it?” and he kept saying no, but the frame was always full of manky water when they replaced stuff. Eventually they figured out he was driving home with the bike on the rack in crap weather, and that’s how the water was getting in.

Didn’t seem to happen to me when I used to use a rack though, and I’ve not heard many similar horror stories, so maybe it depends on the bike and the rack position and whatnot, and that guy was just unlucky. Or maybe he drove everywhere at 150mph, I dunno…

At 150mph it gets clean.. you lot just have slow cars

I’m not sure the excuse “I was just washing my bike officer” when the police pull you over and ask why you was doing 150mph is going to wash!

Ah, memories of putting two bikes on the tow bar rack at Dalby and stopping at the same garage every time outside Thirsk because it was the one all the farmers used and you got hot water and the longest cycle imaginable on the jet wash. Never did any harm as we never put the full force onto the bearings.

I recall Bernard Hinaults mechanic always reckoned that the vibrations on roof racks would pit the bearings – lots of myths in cycling, not much science to back it up. Personally I think that the worst damage is done when people put wet bikes in the shed or garage rather than in the house, because they never dry out fully.

I love that BH mechanic tail, yer cos obviously an unloaded bike with zero weight on it will pit the bearings when loaded with a 70kg rider wouldn’t. Thank f_ck he doesn’t fix my bikes.

I’m sure all the bike shop mechanics will attest. it’s not jet washes or roof racks that shags bikes, it’s numpties who think GT40 is a suitable all-over bike lube…

I avoid jetwashes if at all possible, the one at Cannock is vicious!! THe ones at Llandegla and CYB are quite gentle and just get the big lumps off, I’ll only use them if I’m going to be back late as it make it easier to clean when I get home.

Jetwash your bike and the muck all comes off. Drive down the motorway for half hour in the rain with the bike on top and it’s still dirty.

But 50-60mph while it’s gently snowing polished everything to perfection a few years ago 😆