Lowside uphill Mt. Ham 27 Jan

[glooey]

Here's my analysis based on my post-mortem and the BARF's collective wisdom:

• Cause: bar input over slippy patch --> front tire washout --> bike and rider go splat
• Reason: poor choice of line for conditions and turn. Inside tire track = tighter line = more lean; upcoming decreasing radius = additional bar input. Speed may have been a factor

May be hubris, but I don't think I was excessively yoinking on the bars. I (want to) believe I was providing the inputs required for the line, but chose the wrong line. . .

Takeaways:

• Revert to wide entry / late apexing, including on right turns
• Never get complacent about road surface
• Others?

Thanks for the inputs, all.

 

[ScottRNelson]

Takeaways:

• Revert to wide entry / late apexing, including on right turns
• Never get complacent about road surface
• Others?

Get all braking done before leaning into the turn, but it sounds like you were already doing that.

 

[MapleRoad]

Gotta throw in there that I'm pretty impressed by Glooey's openness to the dogpile. I see so many people who saying "fuckin' gravel" and walk away, or other magic outside their control. It's a tough paradigm to take when you ask "How did I fuck up?"

I suck at it, and it takes WORK for me to do that.

 

[tzrider]

Gotta throw in there that I'm pretty impressed by Glooey's openness to the dogpile.

I agree with you.

 

[glooey]

Get all braking done before leaning into the turn, but it sounds like you were already doing that.

In this situation, there was no braking involved.

I practice trail braking on the street, but only in limited situations where the road surface is clean/consistent (and emergencies).

Gotta throw in there that I'm pretty impressed by Glooey's openness to the dogpile. I see so many people who saying "fuckin' gravel" and walk away, or other magic outside their control. It's a tough paradigm to take when you ask "How did I fuck up?"

I suck at it, and it takes WORK for me to do that.

I agree with you.

Aw, shucks.

Seriously, though, I see this as a public service: With my limited experience and skills, I appreciate any/all learnings, especially if I can get it from SOMEONE ELSE'S mistakes / accidents. I'm assuming riders at / below my level of experience have a similar view.

Plus, if this lowside's going to cost me a few hundred $$ in replacement parts and gear, we better get SOMETHING out of it besides some cool pics.

Cheers.

 

[Gary856]

Most seem to only focus on picking the line to avoid gravel. What about how to handle the slide (front, rear, or both) when you hit gravel for some reason? Hitting gravel and sliding doesn't mean you have to go down.

 

[glooey]

You mean like this?

My lowside felt like <0.5 seconds from loss-of-control to on-the-deck. I'm getting old, but I think I still have reasonable reflexes. I have no idea how I could have saved this one. MM, on the other hand. . .

 

[Aware]

You can save a low-side with a sharp kick to the ground, but it takes sharp reflexes and there's a list of "it depends on ..." to go with it.

 

[russ69]

I bet you unconsciously weight the bars more than you realize and this is just the first time you’ve been caught out. You should be able to take both hands off the bars atter lean angle is set.

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.

 

[Gary856]

You mean like this?

My lowside felt like <0.5 seconds from loss-of-control to on-the-deck. I'm getting old, but I think I still have reasonable reflexes. I have no idea how I could have saved this one. MM, on the other hand. . .

No, nothing like that for us normal riders.

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 didn’t or couldn’t 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. It’s mostly muscle memory, but I also visualize it this way:

- Keep the wheels spinning for gyro-stability.

- 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, it’ll flop down instantly.

- On low-friction surfaces, finish all the braking before the turn, then power thru the turn. When you start sliding, you want to be accelerating (positive throttle) to maintain momentum, not decelerating (coasting or braking) to lose momentum.

 

[ScottRNelson]

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.

 

[glooey]

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.

 

[glooey]

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 didn’t or couldn’t 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. It’s 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, it’ll 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.

 

[kuksul08]

If there isn’t something wrong with the bike, like under inflated tires or ride height that’s 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.

I respectfully disagree with what you've written in this sentence. :x

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. :thumbup

 

[Holeshot]

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.

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"?

 

[Gary856]

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. :rolleyes

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?

 

[glooey]

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.

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. :rolleyes

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).

 

[anytwowilldo]

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.