HOWTO: Ride in the rain

[falcon]

I posted this up in a LNR thread a few weeks ago, but I'm guessing not many people saw it. In light of the current weather, I thought this might be useful for some people, so reposting it here.

These are some notes about wet weather riding I took whilst reading "Proficient Motorcycling" by David L. Hough (Yes, I read a book on safe riding... and took notes ... )

tl;dr BE SMOOTH - Bendito

Surface Traction

• Clean wet pavement provides approx. 80% of the the traction of clean dry pavement.
• However if you loose traction and skid, this becomes approx 35% (compared to approx 75% when skidding on dry pavement).
• There is more on the road than just pavement though, all of the following can be extremely dangerous:
  
  • Oil
  • Antifreeze
  • Dirt & Dust
  • Any painted markings on the road. White, yellow, lines, arrows etc. - Geordie
  • Railway tracks
  • Road conditioner (used in road construction/maintenance to condition the bitumen) - Desmo
  • Manhole covers
  • Bricks / Wood (water mixes with brick dust / wood fibers and creates slippery substance the same colour as the brick / wood)
  • Leaf piles
  • etc...
• Most dangerous when it's been a long time since last decent rain storm, and during the first 1/2 hour of rain, as this is when the road will have the most contaminants (oil, dirt, etc).
• Stay in one of the car tyre tracks as much as possible (duh). Also watch for Buses / Trucks which are leaking oil.
• Watch the road camber, as the bad stuff will run downhill. So e.g. enter freeway ramps in the uphill tyre track, and stay as close as possible to the centre of roundabouts.
• Watch for rainbows / shimmering patches, these indicate oil or the likes.

Hydroplaning

• Occurs in standing water, and is when the depth of the water exceeds the ability of the tyres to expel that water, leading to your tyres "floating" on the water instead.
• Results in essentially zero traction (so you can't steer, brake etc)
• Your probability of hydroplaning increases with the following factors:
  
  • Speed
  • Depth of water
  • Width of tyre
• Under-inflated tyres will create a larger than normal ripple ahead of the contact patch which will trap water an thus increase risk of hydroplaning. - clarified by Spock
• Typical low-profile radial car tyres will start to hydroplane at around 100 km/h in approx 4cm of water.

Dealing With Surface Hazards (Railway Tracks, Turning arrows, etc)

• Try to cross as close to 90 degrees as possible (and a min. of 45 degrees), and as upright as possible
• Place more body weight on pegs.
• Keep throttle steady and don't brake. Snapping of throttle -> engine braking -> eats up available traction. Obviously braking uses up avail. traction as well.
• If already braking, try to ease off before crossing surface hazard.

Braking

• You can use more back brake than usual, as lower traction means less weight transfer to the front, and braking capacity is directly related to how much weight is on the wheel. Aim for 50/50 front/rear.
• Brake in a straight line.
• Start braking early to dry / heat up your discs. Wet disks generally perform very poorly.
• It may take 1 to 2 revs before enough water is removed from the disk. The change can be very sudden, and if you don't get on the brakes early enough, panic and grab a fistful / stomp on them, then the disks will suddenly grab and most likely lock the wheels up.

Misc.

• Keep everything as smooth as possible, no sudden changes in direction or speed.
• Minimum following distance should be 4 seconds.
• If a tyre does loose it, DO NOT snap off the throttle / slam on the brakes. If the bike can correct itself it will.
• You won't hear a car skidding into you when it rains, so be sure to check your mirrors and maintain your buffer zone in all directions as you can't swerve out of the way as easily/confidently. - filbert
• Make sure you can see out of your visor. Search the forums for how to deal with fogging - Murley
• Riding offroad will help you immensely in less than perfect road conditions. - Desmo

If any of the more experienced riders have anything to add, that'd be much appreciated.

[Bendito]

tl;dr option - BE SMOOTH

[falcon]

It's more than just being smooth though, it requires an adjustment of riding technique, and watching out for additional surface hazards.

[Geordie]

Avoid the painted markings on the road. White, yellow, lines, arrows etc. They become like ice when wet!

[falcon]

Ah, thanks Geordie. I've added that to the list of surface hazards.

If any one doesn't want me adding their tips/techniques to the original post (with attribution) please say so.

[SP1RITED]

My advice for seriously bad weather is to drive ur car instead . . .

[Desmo]

Softcock.
Add "road conditioner" to your list of surface hazards too.

[falcon]

Add "road conditioner" to your list of surface hazards too.

What's that?

My advice for seriously bad weather is to drive ur car instead . . .

If you can, not always an option though.

[SP1RITED]

I was waiting for someone to say something like that, I shoulda known u would have been all over it like a fly on shit Desmo . . .

[Desmo]

What's that?

It creates a foam on the road during heavy downpours, very slippery indeed.

[falcon]

It creates a foam on the road during heavy downpours, very slippery indeed.

Forgive my ignorance, but is it something used in road construction/maintenance? Or is it a colloquialism for antifreeze?

[Desmo]

Yes, I believe they use it to condition the bitumen.

[Cbr1k]

...or do what I do.

The confidence these tyres give in the rain is incredible. I've never ridden on racing wets, but I'd be willing these are the closest you can get on a sportsbike.

[Spock]

Good advice generally. Just one thing:

I[B][Over-inflation will make them less likely to trap water, but makes the tread "less resilient" (?) and thus gives less traction.

I don't think that applies to bikes (and I'm not sure what "less resilient" means) - it probably is an effect related to car tyres.

In the end, it's better to have correctly inflated (or even over-inflated) tyres than underinflated, on wet roads.

[filbert]

don't just watch your own following distance, be sure to check your mirrors and maintain your buffer zone in all directions you won't hear a car skidding into you when it rains and you can't swerve out of the way as easily/confidently

[Joker]

good advice, but what people will generally require is practice riding in the wet... get out in it and learn/re-learn some skills.

personally, i love riding in the rain. its the wind i hate.

[lee]

It's more than just being smooth though, it requires an adjustment of riding technique, and watching out for additional surface hazards.

so, adjustment to be more smooth with the inputs? priming brakes before squeezing is a must anyway, as is equal braking distribution (although personally i'd apply more rear than front in the wet). you should also always be scanning the road for hazards, wet or dry.

IMO it's worth running a few less PSI, as less air will allow the tyre to heat up more, which is beneficial to grip.

i approve of your enthusiasm and community spirit, but it's awfully rich a 250 rider giving advice to a forum of primarily experienced riders.

[Kickass Koolridge]

Road conditioner is a load of crap isn't it? Last time I trust Desmo.

I wouldn't write him off just yet cobba, he wasn't fibbing. In this example, Brownclown demonstrates the effects of road conditioner on a dry day.


Vidya courteousy of 'Abuse This'.

[Cbr1k]

Mind if I ask what sort of tyres those are?

They are Dunlop D616's They were 1st marketed as Dual Purpose tyres for the Buell Ulysses. But now that bike has gone, they are marketing them as wets for road bikes. They are great in the gravel, in the wet and on the road. They dont have the vibration that knobleys give you as they are a curved tread.

The only come in 120/70/17 for front and 180/190 17 in rear.

The only downside is they are soft and life is around 5000k's at most.

[Spock]

IMO it's worth running a few less PSI, as less air will allow the tyre to heat up more, which is beneficial to grip.

In the rain a bit more heat won't help. On wet roads, you want to do the exact opposite of what you suggested.