Chassis rescue for the Rivian R1S

In addition to the countless battery and drive upgrades for the second generation Rivian R1 vehicles in detail hereRivian has also released a new suspension setup for the R1S SUV.

This was welcome and overdue, because after our exciting introduction to the R1T pickup truck in 2021, the R1S proved to be a disappointment. This was partly due to Rivian’s price hikes, which made the vehicle no longer have the value it did at launch. But mostly it was due to the R1S’s terrible ride and handling.

Rivian has addressed pricing concerns with price cuts detailed in the previous article, but for families interested in the SUV version of the R1 instead of the pickup truck, the most important news is that they will finally have a vehicle worth driving.

At the media drive event for the second generation R1, two of the company’s chassis engineers gave me an insight into the work they had done to fix the R1S’s handling issues.

“We made changes specifically for the second generation R1S to optimize the ride and handling of this vehicle,” explained Luke Lynch, head of vehicle dynamics at Rivian. “On the ride side, we changed the spring rates so the rear spring rate increases and the front spring rate decreases. This gives the R1S better pitch balance and a more general ride for higher frequency inputs.”

Related:New technology, greater range and lower prices keep Rivian in the game

Rivian uses Tenneco’s innovative networked hydraulic damper system, which acts as both a shock absorber and a stabilizer and uses computer control to adjust the flow of hydraulic fluid between the connected dampers.

“On the shocks, we made some changes to the damping calibration to complement the new spring rate, so the combination again gives you better primary and secondary feel,” Lynch said. “And then we made changes to the bushing pack and upper shock mount to further improve the secondary feel, which is the actual road surface and the visibility.”

“There are a lot of hardware changes for Gen 2 that combine to deliver an optimized or massively improved driving experience for customers on all roads,” he continued. “The driving experience is not easy to quantify, but we have these numbers for acceleration at the C-rail or the overall movement of the shocks over a fixed speed bump or something like that.”

Of course, those same systems also control a vehicle’s handling. And while the R1S’s handling wasn’t as poor as its ride, the second-generation SUV benefited from changes to the system’s tuning in that area as well. “In terms of handling, we made some pretty big or holistic changes to the hydraulic roll control system,” Lynch said. “Most of those focused on bringing the roll balance forward. In a traditional vehicle, you do that with the stabilizers. We have a hydraulic roll control system, so we made changes to the damping hardware to bring the balance further forward. That provides more stability without sacrificing performance, compromising off-road capability, and generally making the vehicle more accessible to more customers.”

Related:Rivian delivers an update to the Enduro twin-engine drive

Pirelli’s 22-inch tires for the Rivian R1. DAN CARNEY

Tires are another critical component, and Rivian has worked hard with its tire suppliers to improve the rubber compound for the R1 vehicles. Tires play a key role in the range of electric vehicles, so it’s important to get this part of the equation right, but without compromising traction or wear characteristics.

“These three tires, wheels and tires, are new offerings for Gen 2,” said Jake Malinowski, senior vehicle dynamics engineer at Rivian. “This 20-inch tire, which we call an extended adventure tire, is the new base offering,” he said, pointing to the Goodyear Wrangler tire.

“This will run on dual motors that are equipped with the (lithium iron phosphate) battery,” he said. “And we’re really happy with how this tire turned out. It’s got a lot of on-road and off-road characteristics built in. It’s a good all-around tire, so it’s good for off-road, on-road, handling, ride, all of that, and it doesn’t sacrifice a lot of range. So we’re really happy with this tire.”

Related:Rivian ushers in the era of electric pickup trucks with the impressive R1T

The 20-inch tire, with its taller, more compliant sidewall, was the size fitted to the first R1T I tested in 2021, and while Rivian is happy with its new 22-inch tire, physics dictates that the smaller wheel/tall tire combination provides a more comfortable ride than the larger wheel/lower profile tire combination. For that reason, I would prefer the 20-inch tire.

The 20-inch Goodyear all-season tire with optional 20-inch Pirelli all-terrain tires. DAN CARNEY

But Malinowski is enthusiastic about Pirelli’s 22-inch tire, which he touts for its dual ability to provide range and handling. “This new 22 actually replaces today’s 21s and 22s,” he said. “Today’s 21 is our range-focused tire, and today’s 22 was more of our handling-focused tire. This new compound that we’ve been working on with the supplier actually gives us the best of both worlds. It actually has better range than the base 21 and handles as well as the base 22. So it’s a fantastic proposition.”

These tires are the choice for the popular two- and three-engine R1 models. For the most powerful four-engine vehicles, there is another option to match their high performance.

“It will be available in the dual and tri-motor configuration,” said Malinowski. “That’s the new thing. It’s specific to the quad motor. And it’s a summer tire offering. And this is actually the first time we’re introducing staggered tire mounting. So the rear tires are 305 (millimeters) and the front tires are 275 (mm).”

On the road, the changes make for a welcome change in the R1S’s driving experience. It’s still not luxurious and not even as good as most SUVs, but it’s probably as good as the Kia EV9, with better handling. Heavy bumps like potholes still rattle the R1S’s occupants quite a bit, but it’s not as jarring as it was before and more routine impacts like bridge expansion joints are no longer wince-inducing events, as they were in the first-generation R1S.

The R1S has also been improved off-road. When I drove the dual-motor R1 on the off-road track at Rivian’s Normal, Illinois, factory last summer, the dual motor was capable but couldn’t match the magical performance of the quad motor. The dual motor uses differentials to distribute the power of a single motor to the wheels on each axle, similar to an internal combustion engine.

Not surprisingly, the dual motor behaved similarly to a combustion-engined 4×4 when climbing hills on the factory track, with brake traction control stepping in noticeably to slow spinning wheels and transfer power to the wheels with traction.

The second generation R1 dual motor rides more like the quad motor, with seemingly imperceptible traction control intervention that let the R1S dual motor crawl through a nasty hole on a hill climb that would have made last year’s version sweat. Like the quad motor, the dual motor now has no trouble traversing obstacles off-road.

This is due to a change in how the engine speed is measured. Whereas the first generation vehicles sensibly measured speed at the engine, the second generation models monitor the engine speed at the inverter. This allows for a more accurate understanding of the engine activity, which in turn allows for more precise control of the engine and prevents wheelspin before it happens. The difference is astonishing and only reinforces the impression that the dual motor has all the features you could want.

Finally, there is the R1’s driver assistance system, which has been lacking so far. Its shortcomings were particularly evident in glare and high contrast, as melting streaks of salt on the road confused the system. There was no opportunity to test this aspect in the dim light and clean highways of rainy Seattle, but the new system’s 10 times more powerful computer and 8 times larger megapixel camera should combine to produce significant improvements.
I can’t wait to spend more time in the R1S. This feeling was not the same for the first generation version.