What causes crashes?

[lonesoldier84]

To be more specific:

What various combinations of rider inputs/situational circumstances cause the following:

1) High-sides
2) Low-sides
3) General instability mid-corner

reason I ask is i have a pretty fair idea of what to avoid doing or be careful of, but a few times I have had a woop! moment from too much of a certain kind of rider input in some given situation.

by rider input i mean things u do with ur weight, feet, legs, hands, whatever. situational circumstances could be sudden swerve, gravel, sloping corner, uphill climb, anything and everything

dont need anyone to write a thesis (tho that would be nice lol ) any feedback is appreciated.

if someone has a link to a great article that would be cool too.

 

[wrightme43]

Go and buy Keith Codes Twist of the Wrist II thats number 2.

Our normal survival reactions cause crashes. They work against motorcycle design, and hurt us.

 

[wrightme43]

High sides are caused by the rear tire getting out of line with the front due to over braking or over accel for conditions and then returning to line putting rotational momentum into the bike and spitting the rider off the top.

Lowsides are due to losing cornering clearance or braking the front to hard leaned over.

Instability mid corner is back to those survival reactions.
On off throttle
multiple turn syndrome. LOL
lack of smoothness
tight on bars
control inputs that work against each other.
stiff arms
many many things.

Mr. Code will help.

 

[chuckfz6ryder]

This link was posted on this forum before, found some great information here, thought you may learn something from it as well.

Motorcycle Safety Site

 

[CCHOUSEKY]

wrightme, you are so completely right about our normal survival reactions causing problems. I almost learned this the hard way last weekend.

I've been working on leaning more, pushing my boundaries, as it were. Up until last weekend, I'd been working on this in a large empty parking lot. Then I went for a group ride with 3 other bikes last weekend up around Louisville. Now, I don't know the road we were on, but they do. Nice, twisty roads without being too hard on a first-timer. The pace was great...the two guys on SS bikes were out in front and would take off through these curves from time to time, then wait while myself and the bike riding sweeper caught up. Absolutely great guys to ride with.

Anyway, in watching the two guys on the SS bikes (a Ninja 1000 and R1) take these long sweepers at higher speeds, I decided I'd work on my leaning. Not going NEARLY as fast as them, but faster than I normally would, I started practicing. Then came this one curve...I saw it coming, downshifted, got to what I thought was an acceptable speed, and turned in. About halfway through it, I started to feel myself panicking...too much speed, I thought. I'm leaning over more than I ever have. Then my survival reaction kicks in and I feel my right foot starting to push down on the rear brake!!! I mean, it was like my body was working outside of what my mind was telling it NOT to do. Luckily, I caught myself just before the rear brake engaged, leaned, pushed, and looked where I wanted to go and everything was fine. But it was DEFINITELY a pucker-moment.

This moment during an otherwise great ride has really stuck out to me. It's scary to think that your natural reaction could possibly do just the opposite of what it's supposed to do.

 

[Rocky529]

If you ever feel uneasy in the middle of a turn, as wrong as it may sound, lean more and give it a bit more throttle.

 

[Botch]

About halfway through it, I started to feel myself panicking...too much speed, I thought. I'm leaning over more than I ever have. Then my survival reaction kicks in and I feel my right foot starting to push down on the rear brake!!! I mean, it was like my body was working outside of what my mind was telling it NOT to do. Luckily, I caught myself just before the rear brake engaged, leaned, pushed, and looked where I wanted to go and everything was fine. But it was DEFINITELY a pucker-moment.

I just had a similar experience this afternoon, on Old Trapper's Loop road east of Ogden. It wasn't speed that made me panic, but a bunch of sand/gravel that appeared on a tight curve (with a big dropoff just beyond). I learned at the top of the road that it was closed for the winter until 1 June, and today's only the 13th; the road hasn't had a chance yet to be "cleared off".

 

[dako81]

Here's my take on the three things you asked about:

1) locking/sliding and unlocking the rear tire while in motion
2) locking/sliding the front tire
3) road conditions, posture, failing suspension component, worn tires, fighting the lean of the bike, riding beyond your skill level

 

[lonesoldier84]

good info

also i should add:

found out dropping the clutch while red-lining in first gear will cause your bike to crash.

 

[Scott]

What do you guys think of keeping your foot off the brake entirely while cornering, or outside of stop-and-go situations in general? To rephrase, would it be safe/acceptable to only use your front AND rear brake while in town?

Riding ATVs for so many years, I've found myself with my foot on the brake too often, so as I come into sweeping corners I've just pointed my foot outward a bit or gotten it in a position where I cannot subconsciously brake with my foot, as I've already experienced how easy it is to lock up the rear wheel. The front brake seems much more forgiving.