Riding through floods

[stinkwheel]

Ok, I am bored tonight and the subject occurred to me after watching six cars being towed out of a flood down the road form work today.

I have some experience of doing this both on and off road and have had extensive drunken discussions on the subject with a friend of mine who rode a KLR650 through the Australian outback for three years and has extensive experience of river crossings (including lashing the bike to a raft made of empty oil drums).

First things to consider are what are the potential consequences both to yourself and the bike. So consider personal safety before deciding to go through a flood. At worst, you could fall off, get trapped under the bike and drown or be washed away in fast flowing water. If you think this is a possibility then don't even attempt crossing by yourself.

You have to decide if you want to continue your journey with wet feet in any other case.

Consequences for the bike depend on what happens.

1) Water on the HT leads or in the electrics will cause your engine to stall. This is not very serious and will eventually dry out or can be squirted with water displacing fluid (WD40). It is more of an issue if you need the engine running to get back up out of a ford. This is only really likley to happen due to spray, if you keep the speed down you will encounter other problems before the electrics are soaked (except perhaps on a sloping v-twin or a moped)

2) water up the exhaust. This can cause the engine to stall as the exhaust gasses cannot escape, keeping the revs high should ensure there is enough pressure of gas to keep it blowing out. It can be an issue with lower exhausts, especially when climbing back out of a ford. If you think the exhaust is under water, keep the revs high and slip the clutch. Again, the bike should restart fine once out of the water.

3) water in the gearbox. It can get in through the crankcase breather, usually on top of the gearbox. It won't kill your bike but you will need to change the oil before continuing (or if in the outback, drain it down, pour off the water from the container -it sinks to the bottom- and allow the remainder to evaporate before refilling it). As a general rule you don't want the water to go over the top of the gearbox.

4) water in the engine. OSHIT! water getting in through the carb and into the bore either by flooding the airbox or dropping the bike in the water. You are in big trouble DO NOT ATTEMPT TO RESTART THE BIKE. The engine could be fluid locked, if you attempt to start it with incompressable water in the engine you could bend a valve, conrod or the crank if you haven't already done so. You need to drain the oil down remove the plugs then either slowly turn the engine over or (if in the outback) turn the bike upside down and leave it to dry.

Most people aren't going to experience a water crossing as extreme as this but the same general principles apply.

So, you approach a flood: Stop and get off the bike, you need to assess if it is possible to safely cross, pick a route through the shallowest part and convince yourself there are no hidden obsticles under the water. Bits of wood and debris can even be washed onto a road, On a river crossing, there can be potholes and boulders. You may have to wade into the water to be absolutley sure.

Pay particular attention to the condition of the bank both going in and out if crossing a river/stream, don't be afraid to move any serious obstacles and even build stones up at the entry and exit points of an established ford (this helps to maintain it in a passable condition and is to everyones advantage).

When you know you are going to go through you have to decide how. At the simplest on a lightly flooded road, you can ride through, feet-up. Deeper water may require you to paddle along with your feet down. Always consider pushing the bike through with no engine running as a safer option. You can cross a rougher area by working with some friends, you ride the bike with either one person stood each side to help balance or one person following through on foot holding the rear grab-rail, this is particualrly useful if there is a slippery bank to negotiate.

Riding a bike through even shallow water is a different experience. The drag of the water will slow you down considerably so keep the gear low and the revs high, don't be afraid to slip the clutch...drag increases with surface area squared so water twice as deep will cause four times as much drag on the bikes wheels, anticipate this. The front of the bike will feel as if the brake is pulled half on so steering becomes heavier and makes a much bigger difference to the direction of the bike than it would normally. This effect gets worse as your speed increases and is exascerbated by a belly pan.

Selecting the correct speed is crucial, too slow and you will bog down, too fast and the bike becomes unhandleable. Ideally you want to be going just fast enough to create a slight 'bow wave' ahead of you, this makes the water shallower and will, with experience, allow you to cross water that is deeper than the level of the gearbox. If you think you are going too fast, do not close the throttle, instead pull the clutch in slightly and keep the revs at the same level, the drag of the water wil slow you. DO NOT STOP, if you do the bow wave will wash back over you and the bike.

Keep going for a reasonable distance after the water to allow other vehicles to cross after you before stopping to wring out socks etc. It is better to take your socks off and just wear the boots on bare feet if you have to wade in, the water will pour out of the boots and the dry socks will mean your feet are just damp rather than soaking.

Well, that was more involved than I intended but it killed some time, I don't expect it is particularly useful to most people but you never know. On one occasion I took my GPZ500 and a friends SV650 through a fairly deep (over the exhaust, about 2/3 of the way up my shins at the deepest part), boulder filled ford on my way to a bothy in mid-Wales. We used a two-man assist and spent about 20 minutes moving stones about before attempting the crossing. It was either that and a 1/2 mile or 15 miles of forestry tracks to get round the obstacle. I suppose we're all young once. I went back the following year on my supermoto and managed to just ride straight through after wading in to check my route.
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[mr.z]

Brilliant

I'd never heared of the gear box thing! :O
Ive not been in the situation yet, but you never know, it is the uk
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>RidingSkills<->Tech Tips<->MyBikes<

[Ste]

One thing to add, don't start going into the flood or ford until there is no other vehicles ahead in the water. If the car in front of you manages to get water up their exhaust or any problem you're then more than slightly stuck. So wait until you have an entriely clear path before starting.

[stinkwheel]

[Reevo8]

didnt know much about riding through floods!! Just when it is raining i take spare socks to work!! And the area around 1mile from my house is always flooded in heavy rain!! up to my feet yesterday. It was dark, and didnt notice the flood at 40mph!

But this wasnt so bad, as where i live flooding is common. So i am used to it, and had much pracice when riding a scooter!

[stinkwheel]

scooter with footplate=jetski
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[Scotty]

Good explanation.
But i'm sure you could wheelie through it all and avoid all dangers
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Regards
Scott

[Sparks!]

Ahhh river crossings...

I thought if I stood on the seat, then I wouldn't really get wet, so I approached said river thing at some speed, (15mph, but that's fast when your about to hit a river ) thinking that I'd blast straight through it!

Well I did blast straight through it but my initial plans didn't work I created a nice massive wave which landed right on my head and competely soaked me

I thought it was funny though

And then went on to ride through a foord with a broken down car stuck in the middle.. just to add to the insult I returned and took pictures he had got himself half way out by the time I returned though but was still broke down in it

https://www.bikechatforums.com/files/ford13-08-04.jpg

Small fords/rivers:

Stand on seat like a poofy girl that doesn't want to get wet, aim towards river a speed, realise your doing a silly thing a slow down, wobble, put foot down in river, give it throttle as a response to the cold foot then slide through the rest of it.

Deeper fords/rivers:

Ride over footbridge


Or if you have no option/stupid/drunk approach river, pray, wobble from not concentrating on the river, get half way across and decide you want to go back, realise you can't turn around so throttle on through, get to near the other side and give it some more throttle.. .. slide out up the other side of river sideways then fall off graciously into a ditch.

Have fun
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Current Toys: 06 Yamaha WR250F | Nissan 350Z GT | Tech 4 Homes

[Kickstart]

Hi

To make this sink in a bit, take a look at this:-

https://www.alfa-pages.co.uk/?go_to=oops

This is what happens when you come round a corner (in a car), see a puddle and think "it hasn't been raining that much, it won't be that deep". The puddle was about 12" deep at the middle of the road. The result was a stranded car, water coming through under the passenger door (below the water level) and a head gasket which had suffered a section being blown out of the side of the engine.

Of course I do not know whose car it was, who was driving, why the car is still on my property and why the remains of the blown engine is in my garage .

All the best

Keith
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Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[aqualung1]

thats wicked R6 but one of thoose pics you have to take
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"still no idea where poohsticks bridge is"
www.bosunsbikes.com

[Sparks!]