Just giving heads-up on a hazard i hadn't experienced or even through about before yesterday:
Following an RV along a straight road - 50mph. Dry road - mid day - perfect weather.
Come to a RH 90 degree curve - I'm two car lengths behind RV. RV takes the curve and a pile of water dumps off the roof onto the road as it is rounding the corner!!! It happens mid corner and I'm already committed to speed/lean. WTH?? That was a new unknown for me. Couldn't take it wide b/c that would be oncoming traffic. Shoulder is gravel. Just braked and hoped. Glad i didn't have more speed on or wasn't following too closely.
sounds like condensation from the roof-mounted air conditioner.
Interesting... I never thought about something like that before.
50mph and you were two car lengths behind something you can't see around?
I think that is the root of the problem. What if the RV went around the corner, saw something and jumped on its brakes?
Increase your following distance and you'll have a hell of a lot more time to react to water falling off the roof of an RV.
Quote from: wbeck257 on July 25, 2008, 05:11:08 AM
50mph and you were two car lengths behind something you can't see around?
I think that is the root of the problem. What if the RV went around the corner, saw something and jumped on its brakes?
Increase your following distance and you'll have a hell of a lot more time to react to water falling off the roof of an RV.
Well, two car lengths going into the corner, when the RV had slowed down to take the corner didn't seem inside the safety margin to me. remember, the RV isn't going to take a 90 degree curve at 50 mph. I don't know what the speed was going into the corner. if I was doing 50 in the corner and grabbed the brakes as I did, I would have low-sided. However, you are correct in that a person needs to allow extra distance for unknowns. You've got your known-knowns and your unknown-knowns (classic Rumsfeld philosophical rambling). The water dump (and it was about four buckets-worth - must have just washed the RV) represents an unknown-known. We know that there are hazards out the that we are not aware of. This was one of them. Take home message - allow enough room that you consider safe and then allow a bit more to accomodate the unknown-knowns.
Quote from: wbeck257 on July 25, 2008, 05:11:08 AM
50mph and you were two car lengths behind something you can't see around?
I think that is the root of the problem. What if the RV went around the corner, saw something and jumped on its brakes?
Increase your following distance and you'll have a hell of a lot more time to react to water falling off the roof of an RV.
2 car lengths isn't adequate following distance for a RV versus a Motorcycle? How quick do you think RV's maneuver or brake?
At 50 mph you are travelling 73 ft per sec, assuming a car length is, if you think a a 1972 eldorado a standard car, about 17 ft, you are 34 ft behind a vehicle or a little less than .5 sec. Good Luck.
Quote from: rose_guy on July 26, 2008, 09:05:32 PM
At 50 mph you are travelling 73 ft per sec, assuming a car length is, if you think a a 1972 eldorado a standard car, about 17 ft, you are 34 ft behind a vehicle or a little less than .5 sec. Good Luck.
Most of us think that 2 car lengths would be enough room and in most cases it is. The RV (or any car) isn't going to stop instantly and leave me only .5 sec to stop or avoid it. Problem is, as in the example, where something falls off the RV, like water, or a muffler and you aren't expecting it. That would leave you with .5 sec to both react and avoid. The water fall instantly changed the road conditions 34 ft in front of me. I instantly realized I hadn't left enough room. I felt completely comfortable with the room one second prior to that.
A friend was driving in San Diego and a rake fell off a gardener's pickup truck in front him on I-5. He was driving a 99 Camry: the rake took out his a/c system and radiator and belts. The rake's steel rake-part bounced into his wheel and took out the rim and front caliper. A $10 garden rake. Couple grands-worth of damage.
You say that following too closley is okay..
Then in the next paragraph you give a perfect example of why following to closley is a bad idea.
The point is to me that you cannot prepare for the unexpected, but being more than two car lengths back is going to help out a lot.
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You say that following too closley is okay..
Then in the next paragraph you give a perfect example of why following to closley is a bad idea.
The point is to me that you cannot prepare for the unexpected, but being more than two car lengths back is going to help out a lot.
Clarification: In my experience, most of the time, given what happens on the road in most circumstances, two car lengths is enough time to react and create a solution to what comes up. However,
I AGREE WITH YOU in that you can't know which situations will arise that will be manageable within two car lengths and which will not. For this reason, a rider needs to allow extra distance.
At 50 MPH you should be, by the old standard, 5 car lengths behind, new standard, 5 seconds. You were also following an RV which is blocking your vision more than a conventional vehicle which means you should leave a little more space. Figuring a typical reaction time of 1.5 seconds you will have covered 55 feet before applying the brakes.
Obviously these numbers I am using are quite conservative safety guru numbers that most of us don't follow but clearly 2 car lengths are not enough at that speed.
Quote from: howie on July 28, 2008, 04:31:11 AM
At 50 MPH you should be, by the old standard, 5 car lengths behind, new standard, 5 seconds.
Where on earth did you get
5 seconds from?
It's two seconds.
A two second following distance is enough to deal with nearly all problems that the vehicle in front of you might present. This two seconds is the same whether you're pulling away from a stop light (don't move until they've been moving for two seconds), following on a twisty road, or driving on the freeway.
I'll pull up closer if I'm about to pass someone, but if I can't get by or can't see if it's clear to get by (e.g., about to go around a right hand corner) then I give the vehicle the full two seconds. The larger they are, the more important this distance is.
If the original poster has been a full two seconds back when the water came off of the RV, there would have been plenty of time to react to it safely.
And I can't think of any circumstances where
five seconds is required.
Forget all these guys.
I don't think you were riding aggressive enough!
You should have backed it in to the corner, on the inside of the RV...pulling a wheelie on exit. That way when the water flew off and went to the outside of the corner you still would have had nice dry pavement. Problem solved! ;D
j/k ;)
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And I can't think of any circumstances where five seconds is required.
I can think of a situation where five seconds is required: My wife decided to pick 7 lbs of rasberries and make jam yesterday. We fought all afternoon. She was stressed. I was stressed by her stress. We got into some pinot grigio from the Alsace in the evening to settle down and make up. I took my bike out in the evening, after draining two bottles with her, to test my snakeskin tank grip inserts that I had custom-cut and installed that afternoon (between pressure-cooking batches of rasberrry jam). Let me tell you - 5 seconds is the minimum time you want to allow between you and anything. Judgement approaches zero, even though you think you have a good idea of what you're doing.
Don't DRINK AND RIDE!!!!
Had I encountered the RV when I was half in the bag..... it would have been a disaster.
I say again - Goddammit - DON'T DRINK AND RIDE.
Wow, you are just full of great ideas. . . [roll]
.
Quote from: ScottRNelson on July 28, 2008, 02:57:08 PM
Where on earth did you get 5 seconds from?
It's two seconds.
5 seconds was a typo. It should have read 2 seconds.
For car driving, the rule is 3 seconds. It doesn't matter what the speed is. It's just 3 seconds. It used to be 1 car length for every 10 mph, but some drivers cannot figure this out when driving due to their depth perception or b/c they are just plain dumb. It's much easier to pick a stationary object such as a light pole or street sign and count from there. That being said, bikes brake quicker and may need less time (2 seconds?). Either way, ride safe or at the least, ride safer. [moto]
Quote from: r_ciao on September 16, 2008, 10:06:22 AM
For car driving, the rule is 3 seconds. It doesn't matter what the speed is. It's just 3 seconds.
So who says 3 seconds is the correct amount?
Who is the expert claiming this?
The safe driving courses have been teaching two seconds for decades and two seconds has always worked well for me as a safe following distance. So who has changed it to three seconds and why?
Quote from: ScottRNelson on September 16, 2008, 11:13:58 AM
So who says 3 seconds is the correct amount?
Who is the expert claiming this?
The safe driving courses have been teaching two seconds for decades and two seconds has always worked well for me as a safe following distance. So who has changed it to three seconds and why?
Anyone who has ever taken the "Smith System" driving courses will tell you 3 seconds.
I've worked at several jobs (all Fortune 500 companies) where driving ed is part of training, all of them you take Smith System.
http://www.smith-system.com/
They claim they are the "global leader in driving training"...
As the US population is aging the magic number is changing from 2 to 3 seconds. Blame AARP [cheeky]
After I started this thread I began paying more attention the distance time thing. I actually took out the tape measure and measured different distances in a parking lot to give perspective.
I also recently bought the new Hough motorcycling book and have been reading that off and on. Bottom line isn't really pinpointing a specific time or distance for following: A person has to be prepared for what 'might' happen. The mistake would be to assume that we know what will happen (i.e. that the car in front of us will continue to drive the same speed) when we know that we do not know (i.e. the car suddenly brakes hard for a squirrel crossing the road in the middle of a corner). Isolating following distance to 2 or 3, 4 or 10 seconds would be a mistake.
Quote from: derby on July 24, 2008, 02:59:52 PM
sounds like condensation from the roof-mounted air conditioner.
Or they washed it. 8)
Quote from: tangueroHondo on July 27, 2008, 11:01:30 AM
I felt completely comfortable with the room one second prior to that.
In my opinion, if you are completely comfortable with what is going on around you you're looking for trouble. I haven't been riding for long but I learned right away that complacency is dangerous. 2-3 seconds may be acceptable in perfectly ideal road conditions, but how often are conditions really ideal? 3-5 seconds may give you enough time to react to something immediately in your path if you are caught off guard, but that isn't nearly enough time to anticipate a hazard.
Why would you want to put yourself in a position of having to execute an emergency maneuver, instead of being prepared for a situation before it becomes immediate? I do realize each situation encountered on the road is different, some factors just cannot be controlled, and this isn't meant to be a blanket statement by any means. But considering some of the most common reasons for single-vehicle fatalities and injuries - failure to negotiate turns prior to crashing, speed, collisions with fixed objects, improper/late braking and steering maneuvers, etc. - why wouldn't you want to put a nice cushion between yourself and what's in front of you to save your own ass?
Again I'm still a noob and more intuitive veteran riders may disagree with me, but I have found the above to be true at least in my own personal albeit limited experience.