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Old 01-29-2018, 06:34 PM   #31
ScottRNelson
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Quote:
Originally Posted by glooey View Post
My lowside felt like <0.5 seconds from loss-of-control to on-the-deck.
I experienced something like that in 1986 when I braked a bit too hard on cold tires. I was down before I knew it. Sometimes things happen too fast to do anything but slide down the road.
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Old 01-29-2018, 08:34 PM   #32
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Originally Posted by russ69 View Post
This, you should have been at the neutral point at that part of the turn and starting to feed in the power. My guess is that steering input was still being applied and the front found it's limit and tucked.
I think you're right.
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Old 01-29-2018, 08:44 PM   #33
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Originally Posted by Gary856 View Post
I think the throttle is the key in dealing with slides. Did you chop the throttle upon sliding, sort of neutral, or hold it open with a purpose?

I slid on gravel a dozen times on bikes including DRZ400sm, SV650, ZX-10R, Multistrada 1000, Speed Triple. Most of the times I didnít or couldnít see the gravel, but I've never gone down from those slides. Sometimes it was over before I could react, sometimes it was worse and I had to do some steering corrections (steer into the slide), but the key was to hold the throttle open steadily, or to open it up a bit more. Itís mostly muscle memory, but I also visualize it this way:

- In a front slide or 2-wheel slide, maintain or increase throttle. Keep the bike moving to allow the front to plow/slide thru the debris to regain traction. If you allow the bike to lose speed during the slide, itíll flop down instantly.
Good question, and I think instructive to emphasize your points about dealing with gravelly patches.

I've had the front wheel push/plow on a slippy patch on the street. Also had the back end kick out 3-5 inches on leaves or sand on the street. Both without going down. Not chopping the throttle seemed like the key, as you point out.

I've two-wheel drifted to a back-end slide out to a slow motion lowside (on dirt) with unskilled application of throttle and rear brake.

Finally, I've tucked the front (off road) due to excessive front brake in a turn -- went down instantaneously (at least it felt like it).

What happened on Saturday felt much more like the latter, except I was on part throttle, no brakes, and (I've concluded) adding bar input. Whoops, down.
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Old 01-31-2018, 09:52 PM   #34
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Originally Posted by tzrider View Post
If there isnít something wrong with the bike, like under inflated tires or ride height thatís way off, Smash is correct, if the rider is lightly rolling on the throttle. If the rider rolls off, the bike will initially stand up, then the line will tighten as the bike slows. With the rider doing nothing but rolling on the gas, the bike should hold its line.
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Originally Posted by ScottRNelson View Post
I respectfully disagree with what you've written in this sentence.

At speed, you don't give the bars any force to the right to "catch" it from falling over further, it's all pressure pushing forward on the right bar - what you're calling turning the bars to the left. Try riding one-handed in a turn and see which way you're applying pressure to the bar.

That being said, the final comment about if you let go it will stand right up would always be the case except that some bikes, at some speeds will fall further into the turn if you let go, not stand up. I had a Ducati ST2 that would fall further into the turn below 25 mph if you let off. It didn't do that at higher speed, but it definitely did it for me at that speed. Might have been the tires on that particular bike...
So I tried this today out on a ride, leaned into a corner got settled, and let go of the bars. Voila, nothing happened! I was wrong.
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Old 02-02-2018, 11:43 PM   #35
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Originally Posted by fubar929 View Post
I think your biggest mistake was setting up in the inside tire track. A better technique for street riding is to setup wide so you can late apex the corner. In this particular case, a wider line would have meant the bike was more upright. The more upright your bike is, the less likely you are to fall over if traction becomes compromised.
Totally agree. Especially with that bank of loose dirt/ rocks.

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Originally Posted by glooey View Post
I was off the brake, in 2nd gear, on maintenance throttle. Given how far the bike slid, I can not rule out speed being a factor - I don't know what my speed was at the time; from the feel/sound I think I was sitting at ~5k rpm in 2nd. I had already set my lean for entry (but see @tzrider below) - it wasn't a sharp bend as you can see in the pics. I was at 36f/38r when I set out in the morning (lowside happened around 1pm).


I probably overplay it, but don't discount contact patch. Uphill, on the the throttle means much smaller front contact patch. If you're still turning and getting on the throttle in a low traction situation, it's very possible to take too much weight off the front. Bar effort + small contact patch can very quickly put a bike on the ground with a rider wondering "WTF"?
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Old 02-04-2018, 10:09 AM   #36
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I re-read this thread and the crash still doesn't make sense. The line might not have been the best, but the OP was taking it easy. He made it near the top fine. That section of the road isn't very tight nor steep, and there was little or no gravel. It didn't seem like the OP was anywhere near the traction limit. Give the condition the front shouldn't suddenly let go unless something was done very wrong.

Thinking about it and not knowing the true root cause was bugging me during most of my ride to Coalinga yesterday.

Questions for Glooey:

- What's your height and weight? I'm wondering how your riding posture was on the Street Triple - leaned forward with bent arms, or upright with straight arms.

- How long have you had the Street Triple? Was the suspension set up for your weight? How comfortable are you with its handling and throttle response on Mt Hamilton? I thought 36F/38R was a bit high but I don't know your weight.

- Where were you looking at the time of the crash?
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Old 02-04-2018, 08:38 PM   #37
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Originally Posted by Holeshot View Post
I probably overplay it, but don't discount contact patch. Uphill, on the the throttle means much smaller front contact patch. If you're still turning and getting on the throttle in a low traction situation, it's very possible to take too much weight off the front. Bar effort + small contact patch can very quickly put a bike on the ground with a rider wondering "WTF"?
Makes sense in general. Pretty sure there was throttle and bar input, though in this situation I wasn't trying to loft the front, and that particular section of Mt. Ham is really not steep.

Quote:
Originally Posted by Gary856 View Post
I re-read this thread and the crash still doesn't make sense. The line might not have been the best, but the OP was taking it easy. He made it near the top fine. That section of the road isn't very tight nor steep, and there was little or no gravel. It didn't seem like the OP was anywhere near the traction limit. Give the condition the front shouldn't suddenly let go unless something was done very wrong.

Thinking about it and not knowing the true root cause was bugging me during most of my ride to Coalinga yesterday.

Questions for Glooey:

- What's your height and weight? I'm wondering how your riding posture was on the Street Triple - leaned forward with bent arms, or upright with straight arms.

- How long have you had the Street Triple? Was the suspension set up for your weight? How comfortable are you with its handling and throttle response on Mt Hamilton? I thought 36F/38R was a bit high but I don't know your weight.

- Where were you looking at the time of the crash?
I'm 5'10", about 190lbs fully geared up. I ride with bent elbows as a rule; in the twisties I also pitch my upper body forward as well (the Street Triple forces kind of a half sport/half standard position for me, so there's already a bit of forward lean).

I've had the Streety for over 2 years and almost 30k miles, suspension set up at a THill East trackday by Jim from Catalyst early in 2016. Since then I've played with the damping a bit for the street but left the sag/preload the way Jim had it (which was definitely different from what I thought was "correct"). The Streety is the bike I'm most comfortable/confident with of the four bikes I've owned (FZ-07, DRZ, FJR are the others), so much so that I have a hard time seeing myself letting go of this bike, ever - every time I think about replacing it, I just go for a ride on it and I fall in love with it all over again (which is neither here nor there, I suppose).

I was looking at the exit of the bend (and may have been peeking towards the tighter right turn ahead - refer to the map link) when I went down. I remember being completely surprised when the bike slid out - I seem to recall still looking ahead towards the next turn as I was sliding, and catching the sight of the bike in my peripheral view. Kind of a surreal out of body experience, as I expected myself to still be attached to the bike.

Assuming this is not a dead horse, I'm still open to other theories. In any case I'm learning something, so thanks for the continued input (but sorry for getting in your head on yesterday's ride).
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Old 02-11-2018, 05:12 PM   #38
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Quote:
Originally Posted by fubar929 View Post
FWIW, I wouldn't be so quick to blame gravel...

The last time I was sliding around on Mines Rd. I didn't see anything on the surface of the road. Finally stopped to check the surface and it looked perfect! Since it was a cool Fall day I took off a glove to check tire temp, which was fine, then put my hand on the road to check pavement temp... and my palm came away covered in sand! Turns out there was a thin layer of those little microscopic ball bearings were everywhere...
+1, I was up there last summer going at a decent clip. Out of a right hander the front then rear let let go, but I was lucky enough to keep it on two wheels. I quickly looked behind me and saw nothing that would indicate the road was so slippery. Sometimes we just get caught off guard. I was more lucky than good that day.
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