fell off today

[bpw]

So had my first crash after three years of riding. Very minor luckily. Had headed down to 9/35 area for a little riding today since the weather was nice and needed to go to the south bay anyways. Had a nice trip down 35 and onto 236, very little traffic taking it easy and enjoying myself. Then went onto Jamison grade, had a good trip up until the very top.

Was coming to the stop sign and touched the front brake to slow down and was instantly sliding on the pavement. Slow speed so didnt get hurt. Broke a turn signal and tore off my left reaset and shift linkage.

I went down so fast I couldnt even figure it out till I walked back and realized the road was covered with sand. What I think happened was:

I came out of the shade into bright sunlight and the road here is very light pavement making the sand almost invisible. I had probably also relaxed a bit after the twisties and may not have looked that closely. Looking at my skid it looked like I locked up on the sand and then hit a patch of good pavement and went down. This was all in about 10-15 feet and the bike slid another 10-15.


Another possible factor is that I had adjusted my brake lever that mornng so it was a little farther from the bars. However it was so quick I dont think this mattered.

I was in leather pants and jacket so no harm done to me. Glad I was geared up though.

Was able to macguver up a peg and shifter and ride home luckily as there was no phone service and I was quite a ways from home.

Not really sure what to learn from this exept gear is good. Was too quick for me to do anything and the sand was really hard to see.

Dont count on phones as there is poor or no service on many of the fun roads. I probably should have been riding with a friend but not always possible.

Ben

[adidas]

I was in leather pants and jacket so no harm done to me. Glad I was geared up though.

:thumbup for wearing gear.

so you were just coming straight to the stop sign, no turns or anything? was it incline/decline or flat?

[bpw]

Totally straight with a slight incline. About the last place you would expect to go down. I was in the center of the lane, If I had been to the side I would have missed the sand. I think part of it was me relaxing after the twisties and just kinda coasting up to the stop with my guard down. But then again you need to relax from time to time or you exhasut yourself.

[emarkham]

there's another good reason to come to a stop in the "tire tracks" (aka. lane position 1 or 3). cars leaking fluids will do so on the middle of the lane.

sorry about your drop. i've done that a few times, once right in front of a car i just passed. talk about embarrassing.

[nweaver]

a: Gear is good.

b: ABS can save your A@#)$(*. Pity they don't make ABS on sportbikes.

[Slowmofo]

The SV650s comes with ABS now and so does the honda interceptor. But these are 07 models. Too bad they didnt make them in the past. So one may ask this question can somone explain how ABS works. If I explain it will sound so mixed up and stupid that it wont make any sense. I would just butcher it

[Nozzle]

Dang, that sucks that you went down due to sand. Glad you are ok though!

My take on ABS:

If the brakes are applied and ABS notices that the tires are locked, it will release the brakes and let the tires roll. It will then reapply the brakes (as you are on your bike's lever or your car's pedal) until it locks up again.

It happens super-fast, so virtually no loss of traction during braking.

[mrslug]

Ain't leather great!

+1 to Glad you are ok.

[Aramaki]

"Not really sure what to learn from this exept gear is good. Was too quick for me to do anything and the sand was really hard to see."

Sorry to hear about your crash. I'll pass something along that I was taught that might help prevent this from happening to you in the future. Your chances of locking the front tire under braking increases as you approach zero mph. The reasons are:

1) weight transfer onto the front tire drops sharply in the last few feet of travel coming to a stop (usually), giving you less front traction to work with

2) the wheel and tire are close to zero rpms as your speed drops, so it doesn't take much for the wheel/tire to completely stop (as compared to when going, say, 70mph)

3) oil, grease, water, and coolant are concentrated near intersections

What I was taught to cope with all this is to always transition from using all front brake to using only the rear brake as I decelerate to a complete stop. If the rear locks, I am much less likely to drop the bike. Once I get below about 30 or so, I gradually apply the rear brake and a moment later begin easing off the front brake. I attempt to do this smoothly enough that a passenger would not even realize I was shifting up my braking. By the time I'm down to about 20mph or so, I'm fully off the front brakes. This way, whether or not I see any debris or fluids on the road, I should be fine.

Hope that helps.

[Trumper]

Sorry to hear about that and glad the duct tape was needed on the ride...not on you.

I've been there and seen that...a couple of times. It's like they dumped a *ton* of sand right at the top of Jameson.

But I don't really know why you didn't see it was coming; that sand starts showing up way back (like a half mile) before the top of Jameson. When you start seeing the patches, you should start slowing way down.

Yep, the sand blends in really well and it's tough to see right at the stop sign (that seems to be where they dumped most of it). But you do get some warning well before that leading up to it....

I don't mean this as a blaming or bashing post...just a note that being hyper-aware of road conditions might help you, or anyone, in the future.

[RhythmRider]

I rode Jamison Creek last week and there was no sand at all. Caltrans removed it mid-March. Not sure what you hit, but I know for sure that there wasn't much sand if any going down Jamison.

[edwinhome9]

another one at jamison and empire... :(

that makes about 4-5 bikes at that one corner.

sorry to hear bout the spill and damage. i know that "not going so fast, wha da hell happened?" feeling all too well.


http://www.bayarearidersforum.com/forums/showthread.php?s=&threadid=196226

[Z3n]

Originally posted by GSXRider750
I rode Jamison Creek last week and there was no sand at all. Caltrans removed it mid-March. Not sure what you hit, but I know for sure that there wasn't much sand if any going down Jamison.

I was up there yesterday and it was absolutely covered in sand. :confused

Either way, it's just one of those things you have to watch out for. Also, stopping in the tire tracks is the way to go...do your best to stay out of the middle of the lane in most situations.

[nweaver]

More on how ABS works...

ABS detects the DIFFERENCE between the front and back wheel (or all 4 wheels in a car). One wheel will lock up before the other, and when it locks up, ABS releases that brake until the wheel starts spinning again.

This greatly reduces braking distance on compromised pavemnet, as the ABS effectively finds the maximum braking force possible before the bike starts to lose traction.

On motorcycles, there is one additional huge advantage: A motorcycle with a locked front wheel wants to flop to the side and wash out the front. ABS prevents this.

On dry, clean pavement, a GOOD rider can outbrake an ABS system by 2-3% by perfect threshold braking. THis is why racebikes, even in MotoGP where it would be allowed, don't have ABS.

On wet pavement, a bit of sand, a bad patch, wahtever, ABS will outbreak even the expert by 25%-50% or more. That is, if the expert without ABS doesn't crash.

The VFR is hardly a sportbike, I have one, its a beautiful gentleman's express, but it is not a sportbike. Likewise, an SV650 is a great fun bike, I have one, but at "only" 70 hp, basic suspension, etc, it isn't a sportbike either.


In Europe, ABS is almost becoming a "must have" item on everything but the full supersport bikes and for some reason the cruisers. EG, the Ninja 650 in europe has available ABS, as does the Z750, Z1000, and ZX-14R (aka ZZR-1400).

In the states it is different. Many riders don't WANT the computer controlling the braking for them. Then again, many riders in the US don't want to wear a helmet.

Me? If Kawasaki US made the ZX-14R have an ABS option in the states, I'd probaly replace my VFR.

[bpw]

More thoughts....

front to rear brake transition, I often do that but unfotunatly was going a little faster than when I start to switch on the rear brake. This happened on first touch of brakes, not while slowing down. The upshot of going down easier at slow speeds is you tend to get hurt less. Physics is our friend in this case. Doubt I would have gone down at 70 in similar situation.

Seeing sand: Probably didnt help that I relaxed after twisties but sand was really hard to see in that light/ color pavement. Didnt even figure out why I went down until walked back over to look. wasnt any sand until the very top (50 ft before intersection). Think it had a lot to do with shade to bright sun transition.

Gsxrrider, Sorry my bad, it wasn t sand but a whole bunch of little tiny rocks, shaped like ball bearings....seriously just cause they sweep the streets doesnt mean no sand. You may not be sure of what I hit but I am. Had lots of time to look at it while piecing my bike back together.

Stop in tracks: Normally very anal about always riding in tracks. Actually trying to get a little less in this habit as I sometimes sacrifice corner lines to stay in tracks. Again was being lazy.

Overall I relaxed rolling to a stop and paid the price. Cant be 100% all the time. 3 years, 30000 miles and one low speed get off. Sucks but guess I was due. I am happy to save my luck for the big ones.

Side note: On the same day I had a small gravel slide from the embankment come down right as I went passed it. Luckily not big and able to ride through. Probably was a sign though.

[raidian]

A simple explaination for ABS/TCS: wheels are being monitored for rotation speed during braking, if any wheel is not rotating while brake pressure is applied, a fine (minimum) amount of brake pressure is released to allow that wheel to rotate; advanced systems will try to make all wheels rotate at the same speed while modulating the braking pressure on each wheel. Most of the ABS won't monitor braking if the moving speed is below certain limit, liker under 25mph for some of the cars.