Riding in the monsoon: water, grip, and what to do afterwards

Rain by itself is manageable. Standing water is the problem, and the finder asks about it directly — "flooded" is one of its road conditions, because across much of India that is not an edge case but three months of the year.

Water hides everything under it: an open manhole, a missing paver, a deep pothole, a kerb edge, a length of rebar. It also moves, and flowing water pushes a two-wheeler sideways. At this catalogue’s median kerb weight of 126.5 kg, yours is not heavy enough to ignore that.

Two things decide it, and neither is ground clearance. Ground clearance runs from 135 mm to 230 mm here, and it tells you whether the belly will strike something. It says nothing about whether the engine will drown.

The air intake

The engine draws air through an airbox, usually under the seat or behind a side panel, and the height of that intake is the real waterline. Air compresses; water does not. Water drawn into a cylinder bends the connecting rod instead. That is hydrolock: an engine-out repair, not a wash and a dry.

The exhaust

A running engine pushes gas out under pressure, so water stays out while the revs are up. The danger is stalling: the pressure goes, the hot pipe contracts, and water is drawn back up it. Cross with a steady throttle and a slipping clutch rather than letting the revs drop.

• Keep the water below the bottom of the exhaust. It is a conservative line, and conservative is right here.
• Go slowly, in first or second. Speed builds a bow wave, and a bow wave raises the water around the intake.
• Feet up on the pegs. A foot put down in moving water is how a rider gets pulled off.
• Cross in one go. Stopping in the middle turns a crossing into a recovery.

An electric machine has no intake to drown and no exhaust to siphon, which helps. It still has a controller, a charge port and a loom, sealed only to the rating in its own manual. Read that before you rely on it, and never charge a wet machine.

Tread does one job: it gives water somewhere to go so the rubber can touch the road. A worn tyre has less room for it. Look into the grooves for the small moulded bars across them — the tread wear indicators. When the tread is level with those bars the tyre is finished.

Two-wheelers aquaplane less readily than cars: a narrow, curved contact patch presses harder on a smaller area and cuts through standing water. That is not the risk worth worrying about. The real hazards are painted lane markings, manhole covers, expansion joints, tar bleed, and the oil film that lifts off the road in the first fifteen to thirty minutes of rain after a dry spell. Cross them upright, with no brake, throttle or steering input.

Pressure is the number on the manufacturer’s sticker, checked cold. Letting air out "for more grip" is a myth borrowed from off-road riding: a soft tyre on tarmac squirms, heats unevenly and steers vaguely.

Stopping distance is v²/(2μg), where μ is the grip available. Take a third of the grip away and the distance grows by half. That is the whole argument for a larger gap in the wet: you are not braking worse, you are braking from further back.

What changes is not how hard you can brake but how quickly you may get there. Grip is a finite budget, spent on braking, turning or accelerating. Ask for all of it at once on a wet painted line and the front tucks. Squeeze progressively, use both brakes, and finish the braking upright.

Brakes matter more here than anywhere, which is why they are worth reading about properly in brakes and safety . Of the 64 machines here, 19 have dual-channel ABS, 10 have single-channel — the front wheel only — 17 have a combined braking system and 18 have discs with no anti-lock at all. In the dry that is a margin; in the wet it decides whether the front wheel locks.

Half of wet-weather safety is optical: rain on a visor, spray off traffic, grey light at four in the afternoon, and headlights that scatter off the water rather than reveal anything.

• A clear visor, always. A tinted one in monsoon light costs far more than it saves.
• Crack it a notch at low speed to stop it fogging. An anti-fog insert is a small amount of money for a large amount of vision.
• A bright rain jacket with reflective panels does more for your visibility than any accessory on the machine. Most two-wheelers sold new in India run their headlamp permanently, but a headlamp in daylight rain is not conspicuous on its own.
• Never a loose poncho or a trailing raincoat. Anything that can reach a wheel or a chain eventually does.
• Clean the headlamp, the tail lamp and the number plate. Monsoon road film makes all three opaque within a day.
• Ride where a driver’s mirror will find you, out of the spray plume behind a bus.

This is the part that decides whether the machine survives the season. Do it the same day; it takes about fifteen minutes.

1. 1

   Dry the brakes first

   Before you park, roll slowly for a few hundred metres with light, steady pressure on both brakes. That warms the discs or drums and drives the water off, so they work the next time you touch them.

2. 2

   Rinse the floodwater off

   Floodwater is silt and sewage, and left on the machine it holds moisture against metal for weeks. Rinse with clean water at low pressure, keeping a washer away from the chain, wheel bearings, fork seals and connectors. Then dry it: a cover over a wet machine does more corrosion damage than the rain did.

3. 3

   Do the chain

   One crossing strips the lubricant off a chain, and a bare chain rusts overnight in monsoon humidity. Displace the water with a dispersant spray, then lubricate it properly — a dispersant is not a lubricant, and stopping there is worse than doing nothing. Scooters run a belt in a sealed case.

4. 4

   Check the oil

   Level and colour. Engine oil that has taken on water goes pale and milky. If it looks like that, do not ride it: it needs changing and the route the water took needs finding.

5. 5

   Check the air filter if you went deep

   A damp filter chokes the engine and a soaked one passes water to the inlet. If it is wet, the water was higher than you thought.

6. 6

   Go round the electrics

   Switchgear, connectors, the horn, both brake light switches, the battery terminals. Dry what you can reach, and put dielectric grease on any connector that has given trouble before.

One crossing is an event; a season is a process, and the process is corrosion. What suffers is what nobody looks at: fasteners, chain and sprockets, lever pivots, connector pins, battery terminals.

• Lubricate the chain after every soaking rather than on the manual’s dry-weather interval. Maintenance and service covers doing it without making it worse.
• Wash the silt and road film off weekly. Corrosion works on what gets left behind.
• Keep the lever pivots, the side stand and the centre stand oiled. A seized side-stand spring is a monsoon classic and a real hazard.
• A machine that sits for days flattens its battery, and a flat battery in a damp season corrodes its terminals faster.
• Check the fork seals for weeping. Grit carried in floodwater is what cuts them.

None of this appears in the catalogue’s running cost, but neglect does: a chain and sprocket set replaced a year early is an avoidable line in what it costs to run .