Safety: Tire & Edge Traps

[TexanRT]

This stretch of road is very popular around town. Most weekends when the weather's clear the motorcycle traffic is steady. I noticed on this particular curve how the road surface looks relatively smooth from one direction -- but coming from the other direction you can see how the pavement surface has separated and drops more than an inch on the other side. During the middle of the day when the sun is high in the sky, you can usually see the road surface imperfections -- but when the sun is low in the sky either in the morning or late afternoon, nearby trees cast long shadows across the road obscuring the hazard unless you're looking carefully.

In this photo taken mid afternoon you might be able to note some of the road surface's imperfections but the shadows are already reducing my ability to see the hazards.

http://www.sterlingresidential.com/images/528.jpg

Taken from the other direction -- this photo shows the damage to the road surface. This is one of the nice sweepers on this popular road and there is pavement damage in both lanes that's hard to detect at speed when shadows are crossing the road.

http://www.sterlingresidential.com/images/529.jpg

I hit a similar spot in a corner recently -- the bike lost traction briefly and slid slightly towards the road edge. The bike recovered traction and I continued on. If I had been riding right on the edge of the traction limits it might have had a different result.

For me the lesson was keeping some traction in reserve. What other types of road or edge traps might be out there? The MSF says we should be looking 12 seconds ahead -- how much of that time is spent scanning the road surface? What might you suggest for "reading" an unfamiliar road?

[henzilla]

Tar Snakes have to be one of those issues for me. Sometimes the county or state maintenance crews fill in the cracks right ahead of a resurfacing project,others seem to use it as a regular maintenance tool. Coming around a corner and rolling across one of these when they are hot, wet, or sandy is always an adrenalin pumper. Since they are not an obvious "bump" in the road ,they can be missed under different weather conditions. Have ridden on stretches of road where they go for miles. After the first slip you just ease up and try to avoid them,which sometimes just is impossible as they cover the majority of the road surface
Wonder if they added sand to the tar if it would help? Not that they are gonna do that...

[dbrick]

Good eye and excellent presentation, TexanRT. The short answer is...anything's possible.
The good things you suggest - keep your eyes open and moving, and maintain some traction in reserve - are your best tools. Experience helps too.

Stay especially alert in uneven, dappled light; country roads under leafing trees come to mind. It is extremely difficult to maintain visual awareness of road surface when the lighting is constantly changing, or when the sun is directly in your eyes. I'm reminded of the local Highway Patrol spokesman, who has observed "When you can't see, the speed limit is zero." He's right.

[TexanRT]

"When you can't see, the speed limit is zero." He's right.

+1 :thumb

[EXR911]

A couple of thoughts:

I don't understand "the MSF says we should be looking 12 seconds ahead". At 60 mph that would be over 1,000 feet and while you would want to recognize other vehicles approaching at that distance you should be scanning a lot of things closer than that as well. You should be constantly shifting your scanning around - near, far, far sides, behind. Then you will pick up the road irregularities, deer in the ditch and so on.

Cornering on a sweeper like you show encourages a racing type of "flattening the curve" by heeling over and "picking a line from centerline to gutter at the apex to centerline at the exit" - which can leave you over the center line at the exit. OK on the track. But I prefer now, even on roads I know well, to scrub off excess speed while the bike is still upright, have a look around the corner to see if it is clear, no surprises in road surface or traffic, then push the bike over into a "late apex" corner and once around, haul it upright and get on the gas again. Some call it "slow in, fast out". Not pretty, but you are not committing you and the bike to an unseen path.

Some places the road crews use "tar and chip" so you have wet tar and loose marble-sized gravel on top.

PT9766

[dbrick]

A couple of thoughts:

I don't understand "the MSF says we should be looking 12 seconds ahead". At 60 mph that would be over 1,000 feet and while you would want to recognize other vehicles approaching at that distance you should be scanning a lot of things closer than that as well. You should be constantly shifting your scanning around - near, far, far sides, behind. Then you will pick up the road irregularities, deer in the ditch and so on.

Yes, the MSF curriculum says 12 seconds, but it also says four seconds, and two seconds. Keep your eyes moving all the time, over all these areas. New riders tend to look directly in front of the front wheel, which is useless: by the time anything is that close, it's too close to change your direction or speed to avoid it. A good rider's eyes are up and moving, and because the "big picture" (thanks, Smith System) is attended to, subtle adjustments in speed, position, and direction are usually all that's necessary.

Cornering on a sweeper like you show encourages a racing type of "flattening the curve" by heeling over and "picking a line from centerline to gutter at the apex to centerline at the exit" - which can leave you over the center line at the exit. OK on the track. But I prefer now, even on roads I know well, to scrub off excess speed while the bike is still upright, have a look around the corner to see if it is clear, no surprises in road surface or traffic, then push the bike over into a "late apex" corner and once around, haul it upright and get on the gas again. Some call it "slow in, fast out". Not pretty, but you are not committing you and the bike to an unseen path.

I agree; this is an excellent tactic for the street. I practice it, too.

Some places the road crews use "tar and chip" so you have wet tar and loose marble-sized gravel on top.

Of course they do, and sometimes slippery stuff appears without human help. I remember one ride in the Sierra foothills, clear day, riding fast good pavement...until the turn became decreasing-radius, the apex was covered with sand, and a large oncoming Oldsmobile was going to get there just when I would. I neither hit her nor crashed, but I had to stop and sit on the roadway for ten minutes to stop shaking. It was a valuable lesson.

[From MARS]

"Close calls" do have a way of "teaching" that is unsurpassed. They seem to really focus the mind. Glad you made it.:thumb

Around here in the winter, road crews fill potholes with crushed rock until Spring makes it possible to do a decent repair, but they don't put up signs warning of "loose gravel ahead". Nothing like a little slide to focus the mind on the ride.

Tom

[TexanRT]

Cornering on a sweeper like you show encourages a racing type of "flattening the curve" by heeling over and "picking a line from centerline to gutter at the apex to centerline at the exit" - which can leave you over the center line at the exit. OK on the track. But I prefer now, even on roads I know well, to scrub off excess speed while the bike is still upright, have a look around the corner to see if it is clear, no surprises in road surface or traffic, then push the bike over into a "late apex" corner and once around, haul it upright and get on the gas again. Some call it "slow in, fast out". Not pretty, but you are not committing you and the bike to an unseen path.

You're correct -- the street rider's safety factor is increased by delaying the apex just as you've pointed out -- I didn't mean to use the term sweeper as the method for making the turn if that's the way it came out. Your method was covered extensively my recent tour in the Smoky mtns. Slow your approach speed by completing your braking before the corner, keeping the throttle open to maintain your speed, approach the curve from the outside of your lane (left tire track for right handers, right tire track for left handers) to maximize your view through the corner, delay the apex of the corner to maximize your view through the turn, then accelerate when you see the curve's exit. That approach was drilled into our heads for three days as we went through hundreds of miles of corners in the mountains -- a method I found particularly important when approaching a blind curve or where a series of curves follow one another.

[TexanRT]

"Close calls" do have a way of "teaching" that is unsurpassed. They seem to really focus the mind. Glad you made it.:thumb

Around here in the winter, road crews fill potholes with crushed rock until Spring makes it possible to do a decent repair, but they don't put up signs warning of "loose gravel ahead". Nothing like a little slide to focus the mind on the ride.

Tom

Yes -- it does tend to focus the mind -- especially for the next several miles. We've got tar snakes, tar and chip and some places it can look like they just threw a shovel full of gravel in a pothole, so you've got to pay attention to the road surfaces around here. Sometimes the areas are marked -- sometimes they're not.

[bikerfish1100]

yup, "outside-inside-outside" is your line to ride. just be aware that on a blind left hander that when you are at the inside point you will be perilously close to the oncoming lanes inside point- i had a buddy smack mirrors on his Duc witha pickup on one of our group rides in just such a situation. apparently, in the mountains, idjits sometimes need more than just their own lane :dunno he stayed upright, and other than a new mirror and his shorts needing a good cleaning, he did fine.
work at always keeping it "between the mustard and the mayo"- and remember that your bike extends beyond the edges of its tires. :thumb

tar snakes? you mean like this? UT 95, NW of Natural Bridges.

[shire2000]

Them there is tire snakes alright.

On Vancouver Island, our wonderful road crews did the Old Island Highway here last summer. Made huge tire snakes. They put the tar on about 1/2 inch thick, then spread sand and fine gravel all over it. Never did clean it up. All last summer we had lots of bikes go down because of it as well as lots of broken headlights, windshields, etc. Everyone complained and the highways department did nothing about it. Finally got some rain in November and most of the excess washed away, but it still feels like riding down a logging road. Extremely bumpy. It is a pity, as the old 2 lane highway was an excellent road for bikes. Some of us are thinking that they did it on purpose, just to slow the bikes down.

:ca

[guitardad]

My worst experience with an edge trap was within my first month of riding after passing the BRC. What should have cued me in first was the way the road surface had been ground down, in preparation for resurfacing. I found the edge trap right at the apex of a left turn, where the opposite lane had already been resurfaced, and the 3-inch lip was about a foot further into "my" lane than where the yellow line should have been. I was still having to work VERY hard to look further ahead, so I didn't see it till I was almost onto it.

Luckily I had enough time to just stand the bike up and let it roll away from the trap, then press and complete the turn. But it was a good lesson in using bothmy eyes and the seat of my pants to "see" what was going on.

[john1691]

After working a long day last summer (rebuilding a storm damaged house, had to get the roof "dried in") so it was dusk by the time I headed home. While cresting a slight knoll, I realized there was a reflection on the road surface, so stabbed the brakes until I got to the reflective area, then coasted though it. The "reflection" was about 1/2" of slurry cow manure coating the road. Appearently, the farmer hit the hydrolic switch a tad early, and coated the road as he entered the field. Fortuneatly I was in my truck, which just required a good wash, had I been on the bike, who knows, as there were cars coming the other direction, and had I gone down, could possibly been run over. I am extra carefull when riding at dusk/night now, as even when you know the road inside and out, you never know for sure what condition it is in!

[yellowrosefarm]

Any time you are riding in bright sun and cross into shade, visibility is cut more than just "less light" would account for. My wife and I were out for a Sunday drive more than a few years ago. We were in the Isuzu pup on a two lane and were passed first by a lone motorcycle, then a short bit later by a pair. They went on to pass several more cars in front of us. A couple of miles further on, traffic came to a stand still. Apparantly, the first bike had ridden right into the back of a dump truck that was sitting inside the shade line waiting to turn left into the gravel quarry. The back of the truck was flat black and the turn signal was not on. Neither were the brake lights, as he was on the clutch getting ready to turn. The guy on the bike was dead on the road shoulder and his bike stuck upright in the dual wheels on the right side. His wife and best friend were the two riders right behind him. I sold my bike (R80) right after that per my wife's request and just this year (actually 8 years later) talked myself and her into getting another (K100LT). The worst road hazard I ever personnally encountered was about 15 years before the above on an R75/5. I popped over a hill on a country road and there was a flock of sheep (like about 200 of the wooly boogers) that had broken through the fence on the left and were all in the road. I was like Moses parting the red sea, but it all ended OK. You really never know what is around the next corner. I don't know that it is any good to ride "scared" but riding "sensible" sure can't hurt.

[bulletbill]

yup, "outside-inside-outside" is your line to ride. just be aware that on a blind left hander that when you are at the inside point you will be perilously close to the oncoming lanes inside point- i had a buddy smack mirrors on his Duc witha pickup on one of our group rides in just such a situation. apparently, in the mountains, idjits sometimes need more than just their own lane :dunno he stayed upright, and other than a new mirror and his shorts needing a good cleaning, he did fine.
work at always keeping it "between the mustard and the mayo"- and remember that your bike extends beyond the edges of its tires. :thumb

tar snakes? you mean like this? UT 95, NW of Natural Bridges.

Love then tar snakes, was through US95 last April and sliding snake to snake was a small jert of the bars, hehe!

[slashsixer]

Sometimes, my riding safety brain needs calibration (I was going to say re-calibration, didn't make much sense) and threads like these help. Lately, my riding opps have been few, so I enjoy the threads regarding riding strategies and hazards.