Hydroplaning speeds

[RT EnRoute]

I know that there are many factors that affect the onset of hydroplaning, tire pressure, tread design, and water

depth, and so on. Is there a generial speed at which I might expect this to happen and how does this manifest itself as far as handeling is concerened ? Does the instability show itsself coming on is stages, or does it come on quickley, as right here right now.

 

[Ignacio]

Is there a generial speed at which I might expect this to happen and how does this manifest itself as far as handeling is concerened ?

Sure. This person answered your question.

there are many factors that affect the onset of hydroplaning, tire pressure, tread design, and water

depth, and so on.

So, I agree with them there isn't one general speed. My sign is a general vagueness starts to develop if there's an extended area covered in the same depth of water (could be 30....could be 70). Then again pronounced vaguess if I hit a giant deep puddle of water and then steering comes back when you clear the water...which is another one of those pesky variables that don't lend one to being able to make definitive statements.

 

[SkooterG]

Only two things affect the onset of hydroplaning. Speed being the most important, and tread design and depth being secondary.

Fortunately, since the shape of a moto-tire is rounded it's a hell of a lot harder to hydroplane than a car. But it can be done.

Don't ride through long puddles of standing water at high speeds. Period.

 

[ahchiu]

Be carreful even at low speeds, you dont' know if there is a sink hole under all that water, I have seen man hole covers blow off in heavy rain and leaving a big hole for you to fall into.

 

[08FJR4ME]

I can only state the facts of my own experience.

Where: I-40 interstate in the state of Tennessee

Road conditions: Pouring cats and dogs with lightning here and there T-Storm.

Riders: 2 up fully loaded

Tires: estimated 2,500 miles on new set of PR2's at the time.

Speed when loss of contact occurred: 85 MPH on dash ODO.

What happened: Front tire still hooked up Rear breaks loose and started getting squirly. Slowly eased off throttle and regained traction around 78 MPH. Held it at 75 and she stayed hooked up the rest of the way.

Am I certifyably nuts? Maybe

Do in need to install spellcheck, yes!

Dave

 

[Auburn]

edit ...

 

[Mr Bill]

I know that there are many factors that affect the onset of hydroplaning, tire pressure, tread design, and water depth, and so on. Is there a generial speed at which I might expect this to happen and how does this manifest itself as far as handeling is concerened ? Does the instability show itsself coming on is stages, or does it come on quickley, as right here right now.

My experience was a lot like Dave's.

I-81

Night

Heavy rain, sort of, it was the tail end of a hurricane

In a hurry to get to the first EOM so going too fast, around 75mph

Bike suddenly started to violently wobble under me, I thought it was a tire blow out so I coasted to a stop and lucky the tractor trailers I just passed didn't run me down

Next day I noticed the front tire looked fine for tread depth until you looked at the sides. Not much tread there and I'm sure that contributed along with the speed.

Back tire was brand new and after that scare I swap both at the same time. The front is the one that moves the water, well unless you do a wheelie through it like AuburnFJR. He thinks the FJR is a big fat dirt bike.

 

[sickchilly]

I can only state the facts of my own experience.
Where: I-40 interstate in the state of Tennessee

Road conditions: Pouring cats and dogs with lightning here and there T-Storm.

Riders: 2 up fully loaded

Tires: estimated 2,500 miles on new set of PR2's at the time.

Speed when loss of contact occurred: 85 MPH on dash ODO.

What happened: Front tire still hooked up Rear breaks loose and started getting squirly. Slowly eased off throttle and regained traction around 78 MPH. Held it at 75 and she stayed hooked up the rest of the way.

Am I certifyably nuts? Maybe

Do in need to install spellcheck, yes!

Dave

I had a similar experience on my old Yamaha V-Star 650 cruiser only it wasn't quite raining cats and dogs and I was going around 60 mph. It was still raining fairly hard by Seattle grey drizzle standards. My front tire stayed planted and in control the entire time, but the rear end I could feel start to float and then it started lightly fish tailing back and forth. I just rolled off throttle until it calmed down and held that speed the rest of my commute. It was a little scary, but I've felt that before on dirt bikes so I didn't need a change my skivvies.

 

[PhilJet09]

Nine times the square root of the tire pressure.

 

[exskibum]

I agree with Iggy -- if the length and depth of the patches of standing water were consistent and known, you might be able to come up with some kind of general rule. The best rule when riding where there is or might be standing water is to slow down. The other rule, which applies to anywhere traction is compromised, is the same one for skiing on ice: don't do anything abruptly. Otherwise, it's a seat of the pants solo, and for the most part every ride in those conditions is different.

 

[odot]

Nice info....was about to restart this thread today at work. So, given any standing water, say an inch.....how fast when one notices total or partial hydroplaning going on? My boss looked at me funny today when I showed up with my helmet at work....and making pools wherever I stood.

I've noticed no hydroplaning at all with heavy rain and well drained roads.....even up to ninety...it's the corners I'm more or less worried aboot.

 

[Donal]

Nine times the square root of the tire pressure.

Well not quite............. at least according to this (click here) According to this guy the formula is 7.95 * sqrt of (tyre pressure * contact patch width / contact patch length). Now, if you have the time and presence of mind to note all these variables and calculate the result then you are already a superior rider and have absolutely nothing to worry about!

 

[Bustanut joker]

Chalk one up for the darkside.. Since my conversion the rear tire has never once felt unsettled in the wet.

 

[El Toro Joe]

Chalk one up for the darkside.. Since my conversion the rear tire has never once felt unsettled in the wet.

Did ya ever ride that thing when it was wet?

 

[Bustanut joker]

Fungi Joe

.. Matter of fact from Grayling to St Ignorance Mi 2 summers ago. Fecking monsoon with FlyinJ on the way to CFO. Jason was following me 'trying to keep up I might add, said it looked like a waterfall behind me.

Last summer from Toronto to Sarnia in another nasty fecker. Tornado touched down about 60 KM north of me. Several days this fall in the damp.

:****:

 

[PhilJet09]

Nine times the square root of the tire pressure.

Well not quite............. at least according to this (click here) According to this guy the formula is 7.95 * sqrt of (tyre pressure * contact patch width / contact patch length). Now, if you have the time and presence of mind to note all these variables and calculate the result then you are already a superior rider and have absolutely nothing to worry about!

I was being facetious, using a "typical" aviation answer.

 

[Bustanut joker]

You can't use words like facetious here.. Sounds too much like feces.

This get's turd burglars like Odie all upset.

 

[odot]

How abouts unctious?

 

[supertankerm60a3]

Other factors to consider when thinking about hydroplaning are road surface cursed bags and foreign materials. Cougar 8000 crashed his riding in the rain, not hydroplaning, as he changed lanes. He crossed a tar snake, hydroplaned on the nonporous material, the bike started oscillating getting worse until it crashed. Hid Bugandy Gen-I was totaled but the bags survived with extensive scratches to both bags. I bought the bags from him a a very reduced price (thanks again Alex (mishacycles)). Point is that nonporous road surfaces, or road surfaces with very low porosity will cause a HydroPlane induced loss of control way before a rough, porous or grooved road surface will.

The other issue is foreign material on the road. Oily film or mud also will instantly reduce the speed that HP-ing starts. I lost it at about 18 on a mountain road because the water I road through was washing dirt across the road. My only damage was quite a few scratches to the right side or silver, most of which were repaired by rubbing out or using touchup paint and a brpken right blinker.

The last possibility is that Alex's bags are simply cursed and like to throw any bike they attached to down at random intervals when the road is wet