Dumped a bike...

[73dart]

Wow, I didn't expect to see so many responses so fast... Thanks to all for the input! I'll include some responses below.

Any prior riding experience or MSF class taken?

I took the basic MSF course to get my license - what a great class! I hope that all the instructors were as helpful as mine were. I did a wee bit of dirt biking when i was younger also, but I wouldn't really count that as experience.

I do plan to take the ERC this spring/summer to follow things up... and I definitely see some track days in my future. I've starting shopping around for racing leathers and trying to find an affordable track class.

Assumming clear, clean, dry pavement, 1 of 2 things happened. Either A) traction gave out as you leaned and the tires slid out from under you. Or B) you were leaned so far over that you dragged something (foot peg?) that didn't give causing the tires to break grip with the ground.

The tires are Metzeler Lasertec's - PO said they're about a year old. I don't think he liked to lean a whole lot; they're more worn in the center than the edges, but still plenty of tread. Looking at the profile of the tires, I halfway wonder if I could have leaned off the tread of the rear tire.

I'm pretty confident it wasn't B - I drag the pegs/kickstand fairly regularly on the GS, so I'm pretty familiar with the feeling. I practiced figure 8's in a parking lot soon after I got the bike until I could put the pegs down on the GS - to the left, the kickstand feeler hits (sucks, cause it's rigid. I'm thinking about taking a sawsall to the little feeler), and on the right, a peg drags. It's hard work to drag the peg cause it's so high up. I didn't want to learn what dragging the bike felt like in an emergency situation, so i decided parking lot practice was in order.

This lowside was lean, lean, lean, on-the-ground... I had about enough time to think "I'm going dow..." before I was sliding. The bike did a lazy half turn as it slid away to a stop, which makes me think that the tires let go, and at pretty close to the same time (back slightly first, bike was on it's right side, rotating clockwise). ie - too fast for the turn. The road was clean and dry; happened around 2pm, so I don't think dew was a factor. no leaves or gravel. If there was liquid in the road, it wasn't visible.

I think you're line thru the corner might reveal if you were going too fast for the curve.

I picked the standard outside-inside-outside line (in my lane) through the turn. I could see all the way through the curve, so I wasn't shooting for a late apex. I went down slightly before the apex, i believe. This turn was on-camber, and inclined.

Hanging off can increase the cornering speeds.

I'm still not sure on the physics of that. I do it sometimes on tight left turns on the GS to keep the kickstand feeler from scraping. I thought the advantage of it was simply that it let you keep the same line, with less lean in the bike - ie, keep in the good part of the tires and keep bike parts from scraping, not that it somehow grants more g's through the turn. But I claim no expertise in the subject...

What I've definately noticed is that the GS and the Ninja weigh almost the same, but the GS's center of gravity is significantly higher. Just a little bit of lean from me changes the angle of the bike in a turn a LOT. If I actually hang my butt off to the inside of a turn, I can make pretty quick turns with the bike practically straight up. Conversely, if I hang off to the outside of the turn, the bike leans waaaaay over to make the same line. So just a little bit of torso lean really changes how that one moves; I think it's the higher CG. The ninja on the other hand, doesn't seem to care as much where my torso is - if I want my body lean to significantly effect how much the bike leans, I really have to exaggerate it - hang my rear off the seat. I think it's due to a much lower CG. tight, low speed turns take me a lot more concentration on the Ninja than on the GS, for sure. But it could very well be that I'm just more familiar w/ the GS.

Two things I would recommend get and study David L. Hough's books "Proficient Motorcycling" (2 books), "Ride Hard Ride Smart" by Pat Hahn and "Total Control" by Lee Parks.

These are definitely on my reading list - I'll be ordering them soon. I've been doing the auto racing thing, so I'm still finishing Carrol Smith's "<blank> To Win" books. I'm almost done with "Drive to Win".

Single vehicle crash at 50 MPH in a corner sounds like racing to me.

And you're right. I was pushing my limits when & where i shouldn't have been. I've always been pretty careful about driving on the roads and racing on the race tracks with my cars; i shouldn't have let my enthusiasm on the bike get the better of me. I definitely need to do some track days when the weather gets warmer. That curve just happened to look like The Perfect Corner, so I opened it up and pretty much committed to the point where I had to either make the turn or crash.

Phew... marathon post. Thanks again for all the responses. I'll certainly be pondering on this for a while.

 

[gustovh]

I am no expert, but do have over 40 years of riding experiance and it sounds like you need countersteer practice.

Back in the early 80s I nearly lost it on a 450 Rebel when going into a 50 mph corner at 70+ and was only leaning and not countersteering, started dragging things and drifting twards the outside of the corner. A 200' drop off the edge. It finaly dawned on me to crank on the handle bars a bit (countersteer) the bike stood up a bit and made it around safely.

If you find yourself in a corner too fast the tendency is to want to brake or drop throttle to slow when the opposite is in order quite often. Crank in more countersteer and throttle up and continue watching your line seems to work quite well. Take your eyes off the line and your toast.

My rule of thumb, ride the bike sitting up until you start dragging things, then it is time to hang off.

GS 1100 LT, Honda 919, GS 550 LT
V

 

[TheCafeKid]

In reality..ive done alot of study on coutersteering and the total more or less oddity of it...try explaining it to someone who doesnt ride, or maybe he does and doesnt realize what is happening when he steers his bike...

At any rate...Hanging off the bike, as you see MotoGP guys do, is completely pointless at normal speeds (even at the speed you state you attempted that turn in.) Im sure alot of people understand the physics of cyclic motion here...so correct me if you think im mis-stating some of this... While it looks cool to hang off the side of the bike like you see your favorite racer do..in normal street riding it is completely absurd. The main reason they are hanging off the bike to begin with has less to do with turning the bike as it does do to with keeping the bike from standing back up at the speeds they are at...as you roll the throttle on, the bike has a natural want to stand up, them hanging off is more to deal with as they come out of the absolute point of the apex, they're still leaned to complete the turn, but already rolling back on the throttle...to slow down the rate of the bike coming back up they add their weight to that side...watch good riders closely..they're still slidding knees, but their center of gravity tends to still be over the center of the bike...and that is the absolute best place for it to be. I'm not saying you dont know what you are doing..i dont even know you...but you,me or anyone else for that matter are not going to PULL the bike over..its the action of countersteer that breaks the tire off the center line of the tread and causes it to lean...you could stand on the pegs all you want with the throttle open, and you're really not going to get that bike to lean...

Its funny how much it blows you away to read about it...even for me whose been riding a while was amazed to learn what actually happens. Tell someone " to turn left, you push the bar right, let it fall off center, and then turn right..." they hear "turn right to turn left..."

Easy good example....sit in a swivel chair with a wheel and tire on a rod...spin it rather quickly and lean it to the left...you move nowhere...now do the same, lean it to the left and then back to the right quickly...you turn right in the chair...
IF you think about it while you are doing it...you'll biff...you just do it naturally... Ive watch a Duc rider in slow motion....his counter steer coming full bore down a strait, slowing and then flipping the bar what looks like near 90 degrees in the opposite direction of his turn....At speed everything you do become exaggerated.

Just my two cents

 

[Steveb64]

That works for me too. Sometimes, when you're into the turn too hot and running wide, what you need is more power. Although, I have said this previously, no one believed me and I was considered to be nuts. LOL As you say though, it is not something for a new rider to be trying. You also have to be going faster than is legal. eheheh

Earl

Often works for cages too! I've been in more situations where getting on the gas has helped me more than hitting the brakes.

Ahem. Yes. I was going kinda fast. But so was everyone else... 8-[ (Club had a very high percentage of road racers, so rides tended to get quite spirited on the twisty bits:-D) Mind you - the area (Wellington) was kind of fun for bikes - only place I've lived, where I wore out the sides of the tyres before the centre!\\/

And the first time was definitely a "Gotta try SOMETHING or this could get ugly!" moment.... :shock:

Hopefully, someone may remember reading this sometime, as they're running wide - and get it to work for them... err good tyres are a must - at the time I was running 18" front/rear wheels, with either Sportscomp Pirelli Phantoms, or the early Michelin Radials... (A/M ??'s). Less grippy may well have dropped me on my arse instead...

Rimutakas pic below...

 

[earlfor]

Hmmmm, I dont think I would want to run off the road in your pic. You could set a record for the worlds longest low side. eh eh

Earl

 

[Steveb64]

Hmmmm, I dont think I would want to run off the road in your pic. You could set a record for the worlds longest low side. eh eh

Earl

It's not that unusual for bikes to end up in the tops of trees, waaay below the road... Cars too. It's on one of the main routes out of Wellington (capital city of NZ), feeding into a large rural area that has a large network of rural roads in good condition, and not much traffic!:-D Consequently, a large number of 'boy racers' (old, young, bikes and cars) head that way for a fast blast. They get all warmed up on some twisties a few miles before, then hit the hill...:shock: