Motorcycle Forum banner
41 - 60 of 72 Posts

·
Registered
Joined
·
872 Posts
Ill admit my Civic was a rollover hazard when it was stock :LOL: It looks like its about to drag its side mirrors on the pavement :ROFLMAO:


Land vehicle Car Vehicle Hood Wheel


It would roll so far, that so much of the weight of the car is pushing down on that wheel when its folded under the car like that, that when I went to yank the wheel back during the transition mid-slalom, it snapped the balljoint. Sheared it right off.
 

·
Registered
Joined
·
119 Posts
Modifying a slingshot makes it more prone to rolling over. Anything you do to add grip makes it want to roll more. The only thing you can do to reduce the roll potential is to reduce the traction. Put like 3 space saver donut tires on it so that it will break traction instead of building so much lateral load. Or add a rear axle or some sort of training wheels type thing.
You really don't know what you're doing in any sense of the word, do you.

I have read many of your motorcycle posts and they're significantly more accurate, though sometimes simplistic in understanding. From your responses here it will remain that way for the foreseeable future.

In the first rollover, it didn't look like he was going any faster than the other two before him. I thought he may have dropped his right front tire off the edge of the pavement, over corrected and flipped himself. Maybe?
If you watch the blue Slingshot before the one that crashes you'll see it push (slide) through the corner (which is about as much slide as achievable with Traction Control on), suggesting there's a lot of speed around a sharp turn. The Slingshot that crashes has the front right wheel lift, suggesting the weight on his rack (and resulting cornering forces) pulled the front of the vehicle up. Cutting the corner sharp could have happened, but that wouldn't lift the front of the vehicle off the ground (at least not by much). Normally the Stability Control would cut the fuel to the engine if a wheel lifted and auto-correct the vehicle attitude. In this case it appears the driver didn't brake and the engine deceleration wasn't enough to pull the front back down, which is understandable as it is a rear-wheel drive vehicle.

The rack, like spoilers people have put on the back, is inadvisable.
 

·
Registered
Joined
·
872 Posts
You really don't know what you're doing in any sense of the word, do you.

I have read many of your motorcycle posts and they're significantly more accurate, though sometimes simplistic in understanding. From your responses here it will remain that way for the foreseeable future.


If you watch the blue Slingshot before the one that crashes you'll see it push (slide) through the corner (which is about as much slide as achievable with Traction Control on), suggesting there's a lot of speed around a sharp turn. The Slingshot that crashes has the front right wheel lift, suggesting the weight on his rack (and resulting cornering forces) pulled the front of the vehicle up. Cutting the corner sharp could have happened, but that wouldn't lift the front of the vehicle off the ground (at least not by much). Normally the Stability Control would cut the fuel to the engine if a wheel lifted and auto-correct the vehicle attitude. In this case it appears the driver didn't brake and the engine deceleration wasn't enough to pull the front back down, which is understandable as it is a rear-wheel drive vehicle.

The rack, like spoilers people have put on the back, is inadvisable.

More grip means you can create more lateral Gs. The lateral Gs are what cause the rolling force. With less grip you have less lateral Gs.

In autocross, they used to allow R-compound tires in the stock classes, and that resulted in a lot of stuff like this.

Car Tire Vehicle Land vehicle Wheel


Because more grip = more roll. If that car had been on low grip street tires then it couldn't generate enough grip to get up on two wheels.

I've personally seen cars up on two wheels. This girl in her stock Mini Cooper on Rs at the Meadowlands a few years ago.

Another example of how more grip causes more roll, is wheelspin. My old WRX autocross car had open differential front and rear. It drove without much wheelspin on corner exit with the street tires, but spun like crazy with the much larger R-comps. This would seem counterintuitive since the Rs have so much more grip, but its because the car is rolling more and taking more weight off those inside tires because there is such more lateral grip with the Rs compared to street tires.


 

·
Registered
Joined
·
119 Posts
@Annihilator, I appreciate you're trying very hard to make a point, that concept is not lost on me. However much experience you have on four wheels, it does not translate to three in the manner you're thinking. Some things are similar, but there are limits to how similar. For more information there is SlingshotForums.com.

Automotive tire Hood Tire Motor vehicle Vehicle
 

·
Retired twice: Navy and as a govt contractor
Joined
·
15,437 Posts
  • Like
Reactions: Annihilator

·
Registered
NRA Life Member
Joined
·
1,447 Posts
All posts have thier points, but were all overlooking the obvious.. there was more than one of the same vehicle, the vehicle was all stock from the appearance, and most likely was rolling on stock tires with a driver that wears a suit by day. Likely with zero knowledge of any aspects of racing...


This, in my mind was some lawyer, or a stock broker who blew some cash on a toy and joined the local club, had a club "ride" meetup, and he got too ambitious with the stock vehicle limits and paid the price.

Seen it many times...and thats when I come blowing by.. lol:)
 

·
Registered
Joined
·
119 Posts
All posts have thier points, but were all overlooking the obvious.. there was more than one of the same vehicle, the vehicle was all stock from the appearance,
As a note, none of the vehicles in the first video (Hwy 160) were stock. (The second video on the track-if I remember correctly-was stock.)

In particular, the blue Slingshot has a soft roof and a carbon-fiber spoiler, LED headlight accents (headlights look like stock housings with LED bulbs).

The yellow one that rolled ("Sassy") has headlight modifications (halo rings and the big one--extra outboard lights--and if one goes that far there are other modifications that came first) and that huge rack out back. (So I looked--curiosity got me: It also has a removable steering hub, air dam inserts, DDM radiator cover, chin add-on, aftermarket seats, extra-tall windshield, cloth roof and supporting tubes, aftermarket swing-arm cover, under-lighting, rear-exit exhaust, graphics package, LED brow lights, cup-holder trim rings, flag mounts w/flags. Rims and tires are OEM up front, aftermarket rear tire.)

The driver may have cut the corner too tight as @Retired Guy said, and that could be a contributing factor, though it wouldn't cause a stock Slingshot to do anything too crazy, even with the center-of-mass shifting from counter steering.

@hogcowboy is right, the driver could have steered left, slammed on the brakes (which are anti-lock), and brought the front back down, then steered right and kept it on the road (from what I can tell from the video, though I wasn't there).

Should they be allowed on the road (to address @hogcowboy's statement): Yes they should, they're quite safe. In this case the owners of the blue and yellow Slingshots chose to make them unsafe, and exceed the limitations of each vehicle (sliding around corners in a group ride is inadvisable). I will mention many of the owners are adults that act like children; one of them experienced the outcome of the several poor decisions they made.
 

·
Registered
NRA Life Member
Joined
·
1,447 Posts
The only real things that they would need to address to acheave the faster cornering speed,
is the suspension, and the tires. swap out the spring in the rear to lower it and give a more progressive rate. the usually stock soft rates give too much springing travel and allows the upper top heavy weight of the rear to swing out with increased G's and get e softer compound tire.

the slingshot already has a low center of gravity, but the length is what kills this. in order for a "tri" foot pront to be strong, it has to be equal length on its distance between its contact point. you see it in bridge and building bracing that use the triangular strength. the atc's from the 80's were too skinny, and top heavy. the slingshot is too long with the highest point of the machine in the single wheel rear. these are just dangerious to the uninformed driver/rider.
 

·
Registered
Joined
·
119 Posts
I agree with the tires/suspension. The shock towers are out of China and hit-or-miss on quality and consistency. Over-all the construction keeps the vehicle price reasonable.

The length is relatively compact, the passenger side is already a bit cramped. Any shorter and it would be like the Can-Am Spyder with a higher COG (sit on rather than in).
 

·
Registered
NRA Life Member
Joined
·
1,447 Posts
Its like me taking a new harley dresser on the track, and complaining that I wrecked it.. well Duhh!

Slingshots are made to look sporty and leisurly ride the roads, not carv the corners..(y)
 

·
American Legion Rider
Joined
·
25,628 Posts
I agree with the tires/suspension.
So do I. Even the Can-Am Spyder corners much better with a suspension upgrade and it has Nanny to keep that kind of stuff from happening. But driver error is the primary problem as far as I’m concerned.
 

·
Registered
Joined
·
296 Posts
So, from the above autocross images, it looks like over-steering a car, on a dead flat parking lot, at excessive speed makes it a 'motorcycle'. Not sure how our local DMV offices classify such.
 

·
Registered
Joined
·
316 Posts
From my perspective it appeared the person driving behind the blue slingshot was on the inside with their right tire close to the curb and wasn't paying attention for what ever reason and cranked it hard right to make the corner after realizing they were aimed in the wrong direction and was short one wheel on the outside rear. Physics and poor design imo.
 

·
Registered
Joined
·
119 Posts
Physics and poor design imo.
Not sure why people have said "poor design." If someone scabbed a huge luggage rack on the back of a Spyder way up in the air and then took a corner too fast do you blame the Spyder? If a semi takes a corner wayyyy over the speed limit and the trailer rolls, do you blame the trailer manufacturer or the guy speeding? In this case a guy puts a huge rack up high and cuts the corner too fast (and possibly too tight), it's obvious bad things are prone to happen.

On a Slingshot it's impossible to light up the rear tire and slide it around a corner without the Traction Control system kicking in and shutting that down. Turn that off and it'll light up and slide, but any sort of serious body roll is shut down by the Stability Control system. Given the front is 2.5" wider than the standard Lamborghini, a stock Slingshot is pretty hard to roll, especially on a banked corner like in the video. After the 2015 slalom rollover there were constant warnings, "Do not turn off the Stability Control system. Turn off Traction Control, but not Stability Control."

They are more fun than I'd have thought, and safer than a motorcycle. Guys here are worried about lawn grass blown on the road--nobody is saying, "A motorcycle is a poor design. A car would handle that just fine."
 

·
Registered
Joined
·
316 Posts
Not sure why people have said "poor design." If someone scabbed a huge luggage rack on the back of a Spyder way up in the air and then took a corner too fast do you blame the Spyder? If a semi takes a corner wayyyy over the speed limit and the trailer rolls, do you blame the trailer manufacturer or the guy speeding? In this case a guy puts a huge rack up high and cuts the corner too fast (and possibly too tight), it's obvious bad things are prone to happen.

On a Slingshot it's impossible to light up the rear tire and slide it around a corner without the Traction Control system kicking in and shutting that down. Turn that off and it'll light up and slide, but any sort of serious body roll is shut down by the Stability Control system. Given the front is 2.5" wider than the standard Lamborghini, a stock Slingshot is pretty hard to roll, especially on a banked corner like in the video. After the 2015 slalom rollover there were constant warnings, "Do not turn off the Stability Control system. Turn off Traction Control, but not Stability Control."

They are more fun than I'd have thought, and safer than a motorcycle. Guys here are worried about lawn grass blown on the road--nobody is saying, "A motorcycle is a poor design. A car would handle that just fine."
Other than they should have cranked the steering left I don't know what to say. Yes they are far safer than a motorcycle and so is a car or truck, but that's not the reason people buy motorcycles and that argument is a strawman.
 

·
Retired twice: Navy and as a govt contractor
Joined
·
15,437 Posts
So, from the above autocross images, it looks like over-steering a car, on a dead flat parking lot, at excessive speed makes it a 'motorcycle'. Not sure how our local DMV offices classify such.

Hey the top was down and I had my helmet on!
 

·
Registered
Joined
·
872 Posts
Given the front is 2.5" wider than the standard Lamborghini, a stock Slingshot is pretty hard to roll, especially on a banked corner like in the video.
No, this is not true. The wide front track width only gives you lots of roll stability under braking. Because under braking all the weight of the car is transferred off of the nonexistent rear axle and onto the wide front axle. Under braking you could just about have 0 wheels in back and it wouldn't cause much ruckus.

But under acceleration the opposite is true. Under acceleration all the weight transfers from the front axle onto the rear axle, which is only like 10" wide. 10" of width gives you literally no roll resistance.

Turning while:

Braking = likely almost as stable as 4 wheels
Cruising = 50% as stable as 4 wheels
Accelerating = you turn into a tumbleweed

If he had been descending the hill instead of climbing it, speed and all else being equal, he probably wouldn't have rolled.
 

·
American Legion Rider
Joined
·
25,628 Posts
After the 2015 slalom rollover there were constant warnings, "Do not turn off the Stability Control system. Turn off Traction Control, but not Stability Control."
Was it a given fact the driver DID turn off the stability control? That would certainly be the answer to why it rolled. That is the safety factor for those things. Add in an unexpected up draft coming up that side of the hill and boom, you're a goner.
 
41 - 60 of 72 Posts
Top