What happens is that in an overly aggressive cornering, the rear motors go into the kind of vectoring that you might have experienced if you've driven an old fashioned Honda or Acura equipped with a Torsen axle.

This could be anything like the DC2 ITR to the modern day Civic Si Coupe.

If you've pushed it to the limit, the car starts hunting for traction left/right, left/right, left/right until you're done with whatever it is you've done to provoke this.

I'm sort of used to this because my '00 ITR #110 ended its life as a high HP K Motor hybrid with a mechanical Torsen axle on the front end. You got used to it and expected the car to hunt left, right, left, right if you pushed it beyond what was normally logical.

But we should not drive that way on the street. It's there for an ultimate handling scenario and controlling it can be unexpected if you're not prepared for it.

What happens with the Sport Hybrid when you push it that far is very similar, but with one major exception: Since it's happening at the back end of the car, it can have an adverse effect if you're not prepared, causing an inexperienced driver to provoke wider yaw angles trying to correct something that does not need correcting, and before you know it the car will intervene aggressively, thinking that you've lost control....and maybe you are about to lose control without the car's intervention.

If you watch the video of how the car handles roads that are partially iced over, you can see a visual representation of how the rear motors power left/right, left/right until you're on solid ground.

On dry pavement, a roundabout or a hard corner isn't necessarily going to have consistent and appropriately abrasive traction across the entire section of it just because it is dry.

Moreover, if you've pushed the car to its limits it is going to lose traction somehow, on one side or the other first, and when it gets traction on the lost side it might have lost it on the side that had traction when you started this unwise maneuver.

At some point the car is going to intervene because it will think you've lost your mind and the car's on the verge of going out of control.

But it is possible to be at the limit without intervention, with the rear motors searching for traction at the tail end while at the same time trying to keep track of what you are doing with the greater power on the nose of the car. One or the other of the front wheels is probably not at full grip while you're doing this, either, and you don't have a Torsen axle on the nose the way you did in your ITR or your old six speed TL, which further exacerbates what the computer is trying to do with the rear motors.

The Sport Hybrid is in no way any kind of super car.

However, it has a hell of a lot more power than we are used to seeing in a Honda sedan, and if you don't realize that it is not a Glorified Accord then you might be in for some surprises.

 

In addition to the tail end issues they note they had and repeated, on dry pavement, how about the issues they reported when they tested another example of an RLX SH-AWD with sudden-onset understeering the following week:

"Another Sport Hybrid we drove a week later kept its tail in line but surprised us instead with sudden-onset understeer through one fast curve. Of course, the stability-control system quickly reined in any waywardness, but this was hardly the sure-footedness we expect from an all-wheel drive car."

Do you believe that reported issue is the same root cause you note or another separate issue?

Would you expect either or both of these reported issues in similar circumstances to also likely happen to the same level with the TLX SH-AWD, and PAWS model of RLX and TLX?

 

Objection to the premise: the use of the word issues. We are not sure they are issues.

The fact that they were experiencing the phenomenon in the manner they described might indicate that they were driving at 10/10 or even 11/10 and on the verge of the car's safety systems intruding.

Encountering what they perceived as understeer could mean that the car learned its lesson and interfered with what they were trying to do.

I've never encountered "sudden understeer" in any situation, and I am an enthusiastic driver.

I have encountered the rear end hunt.

 

Hmmm. I've never, ever encountered what those reviewers did. Of course, I'm not dumb enough to attempt 10/10 on a public road like they did. When driven like most people will drive the car, it is completely neutral in a turn other than a teeny, tiny bit of understeer in steeper turns.

 

I'm am a little in the dark on all of the technical babble. I respect George's knowledge and expertise but really have had difficultly following his detailed explanation. It is beyond my ability to fully comprehend.

My takeaway is that the problem mentioned in the Globe/Mail article is nothing I am likely to experience even though I do enjoy pushing my car through twisty mountain roads. I realize that my driving skills have their limits.

Could someone post a link to the article in question so perhaps I can better understand George's analysis? Thanks

 

Review: Is the 2015 Acura RLX Sport Hybrid fully baked? - The Globe and Mail

 

For its intended market I don't think the RLX base or hybrid drives improperly at all

 

Out of all the reviews of the Sport Hybrid, this is the only one that gives a negative about the handling. If other reviewers and actual owners, of which there are six so far on the site, found similar problems, then I'd give more credence to the single review of many mentioning this "issue".

I'm a pretty enthusiastic driver and, again, no handling issues.

 

Respectfully, Jeremy has strong credentials. He was thorough enough to also test and report on another RLX-SH the next week and reported both results.

Jeremy Sinek (B.Sc. Eng.) has been a professional auto writer since 1973. His career began in the U.K., where, as road test editor of Motor magazine, he acquired an expertise at instrumented performance testing. He is also a former editor of World of Wheels magazine in Canada. As a freelance he has been widely published in Australia, South Africa and the U.S. as well as Canada. Sinek is a two-time winner and four-time runner up as Canadian Automotive Journalist of the Year.

 

^^^Exactly right. Anyone can take any car in the world, even a LaFerrari or McLaren P1 and make it get loose or "squirrelly" if they drive it like a complete idiot. I place absolutely ZERO credence in the findings of the review in question.

The more likely scenario is that the handling of the Sport Hybrid RLX was so much better than the reviewer was expecting from such a large car, that he pushed and pushed the car harder and harder in turns until the electronic safety devices in the car were all engaged which surprised him causing him to get jumpy and over-react.

Just my two cents.

 

Ok. I read the article and tried to think through what the writer is discussing. First a little bit of regurgitating from the Acura site. The Hybrid has a number of suspension features that are designed to keep the car flat during maneuvers to include thicker roll bars and anti dive setup. All of this means is that the car will STICK to the road when pushed hard; let's remember that only a patch of rubber is doing the hard work when the car is moving; and the more technologies keep this rubber glued to the road the more you are going to feel the car.

So, what does this mean?

If pushed hard as a FWD, the front will plow and understeer as the wheels are both turning, rotating, and carrying 63% of the weight....not good. You have to play with steering and rear (hand) brake to make the rear end brake in dry conditions. In wet conditions you can create a condition where you fish tail the car when braking hard and steering at same time...remember the weight is in the front of the car if FWD.

But the Hybrid is not just a FWD--it is an AWD with TQ vectoring, and its weight distribution is also different and improved. More weight towards the rear gives it a more neutral feel during rotation. This feel is enhanced by braking or speeding up the wheels during turns.

So if the car fishtailed in dry conditions I can recreate the situation by yanking the steering to either side and by accelerating and decelerating and accelerating again very fast. When approaching a turn at speeds greater than the turn will "normally" allow I would want to fishtail the rear, and accelerate out of it. This is normal. In the case of the Hybrid the TQ Vectoring SHAWD system will predictably react by trying to get the car back in a safe line/mode. Fishtailing should not happen in dry conditions but you can force it. I am curious on what maneuvers the writer was performing, entry speed, weather conditions, etc...

As to understeer, I have been able to get the SH-AWD to do it by employing the same technique of steering hard and accelerating at same time. Because it is still front weighted this should be expected.

Finally--tires. It is all about the patch. The stickier it is and at the right temperature it will delay departure from traction and allow all of the electronics to do the job.

Once again the article did not explain the tests they were performing. So hard to tell whether it is a technical issue, driver capability/prowess, or just plain dumb luck.

I can get Porsche, Jags, Peugeots, R5Alpine, Alfa's, and Mitsu Lancers to fishtail and understeer and I have. You have to understand the circumstances and then worry if it is car, the driver, the conditions, or the maneuver.

I truly enjoy driving the SH-AWD and given its size it handles better than my expectation. It does not handle as well as souped up Miata but then again I don't expect it to nor will I drive it that way.

My 3 cents ;-)

 

This thread made me go back and look at my thread from my test drive. Here is a quote from my test drive:

One last comment. I had one unexpected experience when I was "carving" through a sharp turn at a good clip. I must have cut the corner too sharply and the car's computer literally threw me back into the middle of the lane. It startled me some and was very abrupt. I felt in complete control [perhaps I was fooling myself but I think not] ,so it was a shock. I imagine it was one of the tech features, all of which were turned on so I could see what they do. Still it was nice to know the technology wanted to protect me. Also, these feature do have an off switch so I can test my driving ability without a safety net if I want.

After reading the Mail/Globe review it sounds like the same thing. The only difference is since I am not an experienced race driver, I thought I was still in control. Probably just my bad....the car's computer thought differently. I really don't think I ever lost traction on my test drive. I assume now that it was probably the Lane Keeping Assist kicking in and not caused by a loss of traction.

Here is my takeway.....any car can be pushed over the limit. The real question is what happens when it is pushed too hard. With the Sports Hybrid the answer is that the car realizes there is a problem and works to correct it....quite effectively it seems. So I view this as a positive, not a negative. I can't comment on whether or not the "competition" handles this pushing to the edge any better but I am happy with how my car handles things. While it is a shock when the car takes control, it is better than what could happen.

Lastly, as I have said many times...the Sports Hybrid is not a true sports car but rather a large, comfortable luxury 4 dr. sedan that is powerful and handles well.....and that's what I am looking for.

 

I guess I'm driving my car not nearly hard enough to induce this behavior. Not many curves here and the weather has been like January since I took delivery.

Thanks for the explanations from the expert drivers, they are helpful.

 

Your opinion is no less valid than mine, so don't take this the wrong way, but if he was getting 5.8 s to 100, then he wasn't expert enough or thorough enough to put the danged car in first gear.

:-)

 

George - What does "driving at 9/10, 10/10, 11/10, actually mean? Is it a term of art used in racing?

 

He means, driving "balls to the wall", or close to, or surpassing. Essentially pushing the car right to its limits.

 

Bottom line is he reported the tail end having (choose word you like to describe the tail end of a car not handling well from a professional perspective) on multiple tests, on dry pavement, and another separate model with sudden onset understeering on dry pavement the next week, when driving what he described as "briskly". If others have other results that is great but this made a major publication from a credentialed guy. Not sure what you mean about the times he recorded but any issue could have been him or the car. Right?

 

I just LOL'd hard over your Avatar / Quote...

 

Continuing objection to the premise: A car that is trying to find traction when you've pushed beyond the limit is not necessarily doing anything wrong.

However...I will discuss this with other people, although it will be a week before I will be in a position to discuss it with people who would have the provenance to understand what I was saying and who would be in a position to do something about it, if something does indeed need to be done about it.

If you flash the car to intervene earlier and prohibit this search for traction then you are limiting the ultimate performance of the car.

 

A 4G TL 6-6 SH-AWD when pushed in the same fashion, right up to and beyond the logical limit, will search for traction at the rear in the same left/right fashion. This was not two separate motors, of course, but the Acura clutch pack, electronically assisted LSD that was unique to this car.

And any number of Honda Challenge racers will describe the same phenomenon to you under circumstances they're accelerating all out in a straight line with overheated tyres, or if they're accelerating hard out of a corner and their mechanical LSD are searching for traction the same way, except in that case the LSD is trying to pull you out instead of push you out the way the 4G TL and Sport Hybrid operate.

 

Pretty much. :-)

11/10 hints that you might have exceeded your competence or the car's logical capabilities.

 

This doesn't surprise me in the slightest. Auto reviewers always have a beef about something. If we were hearing about RLX's crashing on the news or on NHTSA's site, I'd say there "might" be a problem. But, this appears to be a one off. I can guarantee one thing...once Honda got wind of this, they'll be testing IMMEDIATELY.

 

It's hard not to take umbrage because people continue to speak of this as if it is some kind of problem.

It is a normal left/right search for traction that any LSD would make at the limit, and the two rear electric motors are trying to do the same thing in emulation of what a hard driving person would expect.

I wish that I could take you all out to Turn 10 or Turn 5 at Summit Point and show you why you want this.

It's all really very unfortunate because I believe that this is not a surprise to the Japanese Design Team or the engineers at Saiyama. Ichishima himself was one of the consultants...it is the kind of behavior that drivers like him would expect when a car reaches beyond its limits.

And it's unfortunate in a different way because if there is too much outcry they will dial it back because too many people are afraid of it, and while it's fine for 250 cars in the hands of driving enthusiasts, it might not be something you want on the road if they are building 5,000 5G Legends in Ohio for more average American drivers.

I understand why people are worried about it, but it's just kind of too bad.

And I apologize if I appear to become in any way impolite when I am talking about this. It hits at home, because I am precisely the kind of buyer and driver for whom this car was designed.

 

:-)

 

*Bob ducks in for a second*
I for one, hope they don't "dumb down" the system because of comments from one journalist.

PS, thank you again for your informed explanations of driving dynamics. I, for one, REALLY appreciate them.
*ducks out, back to work*

 

H E "DOUBLE HOCKEY STICKS" YA! Do not reflash to limit performance. Go out on the track and learn the limits. Then drive up to those limits (solemn voice: please follow all local safety laws and common sense rules) but do not exceed them. When I am asked to help someone learn to drive I always have them; at the right time; learn the max stopping distance, acceleration, adhesion, turning radius, fast speed cone avoidance maneuver--not because they will drive that way--but because it helps them learn what the car can and CANNOT do. How many tailgaters acutally know what the braking capability of their car is--first they should not tailgate and second they are not ready for the probable but unanticipated. Yeah, I know, WHO DOES THAT when learning to drive or getting in a new car (at anytime)? Well, a small percentage of us still enjoy our cars--;-)....the clutch bills prove it!

Right on George and agree with you "duck" Bob.

 

Agreed...to wit--CR's test of Outbacks with claims of rear stepping out; Jeep's moose maneuver failure, and the famous Samurai....

No one wants to drive a faulty/flawed car that does something other than what the driver induced or reacts in a manner that is not consistent with safety designs.

 

I agree with the comments above.

The RLX Sport Hybrid is a 4200+ pound sedan that is primarily designed for a smooth, comfortable, quiet ride. As a nice bonus and thanks to some amazing technology, it happens to offer exceptional handling that belies it's size. That does not mean that you can take the RLX Sport Hybrid out for your first drive, engage all of the safety driver aids and then "bitch" that the car's safety aids kick in while you are driving it as though on a race track. Malibu Flyer's comment that something as simple as the LKAS system kicking in while the reviewer veered out of his lane during a particularly aggressive cornering maneuver, seems to be a very logical explanation for what the reviewer described as "squirrely" behavior. Regardless of which safety mechanism or dynamic handling feature kicked in, as George has stated repeatedly, this is not a fault or a problem. Period. If anything, the RLX SPort Hybrid was trying to tell this fellow that he was driving in an unsafe manner, either disengage the safety aids or get yourself to a race track to continue driving this way.

Finally, 95%+ of the driving most Sport Hybrid RLX's will do has nothing to do with 9/10 or 10/10 handling and has everything to do with the smooth, comfortable, quiet ride it was designed for, so don't judge it based on one reviewer pushing it past it's (or his) limits and seemingly just looking for something to complain about.

 

I concur 100% with hondamore. I do wish to add that if you want to drive the car at 8/10 or 7/10 it is a whale of a nice ride, without any "Squirrelliness". It is comforting for me to know that if I miss judge what 8/10 driving is that the Acura nannies will kick in and keep me safe and sound. I would rather get a surprise lurch back into the middle of a lane than end up in a ditch with a mangled 4,200 lb. mass of metal.

 

Me, three.

 

Same here, this car was designed for ME as well!

I think too many writers, especially those over a certain age, fail to understand the complexities of modern software controlled system on today's vehicles.

As you noted, his acceleration times point to the fact he failed to get first gear starts.

More and more, I trust the reviews of actual owners over the "pro's", as too many things are only learned over extended ownership and a willingness to invest the time to learn.

These threads from the owners of the SH RLX tell me a lot more about this vehicle and how it might apply to me than many of the published reviews.
It's interesting that the contingent of serious RLX prospects and owners are all a bunch of smart, respectful and open individuals willing to share their knowledge and experience. Makes for a much more interesting ownership prospect for me.

 

Jeremy Sinek's review in the Globe and Mail appears even handed, realistic and fair. Unfortunately I'm running out of patience and years (my age) to hang around much longer waiting on the "proper" RLX...

 

I wish the reviewers would explain what they were doing or were in the process of doing so that the layperson can understand what occurred and why it occurred. While not a big follower of youtube I do believe that a visual record allows for greater and better presentation of events as they occur and allow for enthusiasts to determine whether the claims are founded. So, the review does read as fair other than not knowing what exactly happened...

 

They were in a roundabout trying to see how fast they could go.