Volvo XC40 Forum banner
41 - 56 of 56 Posts

·
Registered
Joined
·
227 Posts
I've been watching this thread for several weeks and I've been off reading about tires/wheels at Volvo sites and high performance automobile sites. I have ZERO experience with this concept that 1/2" change in overall radius can effect such dramatically sensible changes in ride quality, cabin noise, and handling. I've seen that car mass, properly tuned suspension, and the many variables of tire/wheel construction and design (depth, thickness, pressure, compounds, width, tread style, mass) all contribute to the feel of the car on the road and cabin. I do NOT get the sense that merely changing from 20s to 19s makes all that much difference unless one takes all the other factors into consideration and can make an informed decision. And I am left with the (perhaps naïve) impression that Volvo is outfitting the C40 with the best tire/wheel for the twin motor version.
 

·
Registered
2022 XC40 Recharge Twin Fusion Red
Joined
·
1,259 Posts
I've been watching this thread for several weeks and I've been off reading about tires/wheels at Volvo sites and high performance automobile sites. I have ZERO experience with this concept that 1/2" change in overall radius can effect such dramatically sensible changes in ride quality, cabin noise, and handling. I've seen that car mass, properly tuned suspension, and the many variables of tire/wheel construction and design (depth, thickness, pressure, compounds, width, tread style, mass) all contribute to the feel of the car on the road and cabin. I do NOT get the sense that merely changing from 20s to 19s makes all that much difference unless one takes all the other factors into consideration and can make an informed decision. And I am left with the (perhaps naïve) impression that Volvo is outfitting the C40 with the best tire/wheel for the twin motor version.
that 1/2-inch change is in the radius, which includes the wheel and tyre. If you look at the tyre itself (the only flexible part of the system) then 1/2 inch is a fairly large percentage increase in space between the wheel and the road. 255/40R20 tyres (rear size for the Recharge Twin) have a sidewall height of approx 255 mm x 40% = 102 mm. The 19-inch rear tyre is a 255/45-19 which has an approx sidewall height of 255 mm x 45% = 114.75 mm. So the increase in tyre space between wheel and tyre when going from 20 to 19 inch wheels is 114.75-102=12.75 mm (makes sense - half of 25.4 mm, which is the decrease in wheel diameter, to be expected given they want to keep the overall rolling radius the same), or 12.5%. The percentage is not insignificant, but not as large as I had thought it would be after doing the calculations. :) Edit: I corrected the tyre size as I had it wrong initially. Second edit: I compared the actual tyre size between 20 and 19 inch wheels.
 

·
Registered
Joined
·
15 Posts
And I am left with the (perhaps naïve) impression that Volvo is outfitting the C40 with the best tire/wheel for the twin motor version.
I, respectfully, think you're being naive.
Big wheels look cool.
Big wheels accommodate big brakes.
Heavier cars need bigger brakes.
Big wheels often are heavier than smaller wheels.
Big brakes look cool.
Big , heavy wheels are not as efficient as smaller lighter wheels.

If the intent was a sporting ride, the XC40, while fast, is not a sporting ride. The tires being EV oriented are not as grippy as could be and the suspension is not set up for canyon carving. I have driven SUVs that inspire more confidence in the Twisties.

If the intent was getting more range, they would have chosen lighter and smaller wheels.

For comfort, it's hard to say because it is subjective. My wife's RS5 with 35 profile, 20 inch wheels and grippy rubber is kind of rough when driving in NYC. On smooth interstates, it's fabulous.on Twisties it's a pleasure and confidence inspiring compared to the seemingly faster xc40.

Given the similarities between c40 and xc40, the argument of Volvo offering the best implies they knowingly gave a less than best option in the form of standard 19's on lower trims.
When I had an EV mini Cooper, I chose 17's for looks and grip in the summer and used lightweight 16's in the winter. The 16's were perceptibly faster, quicker to respond steering inputs, and gave a tiny bit more than expected range .

Get 20's if you think they look cool
Get better rubber regardless of size unless you're more concerned with range.
 

·
Registered
2022 XC40 Ultimate, Sage Green
Joined
·
267 Posts
So I picked up my winter tire package from Volvo today. 2022 model 19” rims with Pirelli Sottozero’s. We get snow and sub-freezing temperatures here next week, according to Weather Network and it’s hilly where we live on the coast. Not a good combination with ice. The ride feels noticeably softer and thankfully at city speeds, the tires are no louder than standard Pirellis on the 20” rims. Highway to 90kph - some additional noise plus a few harmonics I expect from chunkier treads, but nothing like the noise I had from Nokians on my old work vehicle. Certainly not annoying. Based on advice from the dealer, I think the 19’s are the best option for the Recharge and they certainly look good. It’s more expensive to get the Volvo approved setup perhaps, but considering the outlay for the car, spending $4000 Cdn on tires and rims over the life of the tires is not an unreasonable expense IMO. And, you know it has been tested and approved in the event something goes wrong under warranty.
Tire Wheel Car Vehicle Automotive tire
 

·
Registered
Joined
·
227 Posts
I, respectfully, think you're being naive. Big wheels look cool. Big wheels accommodate big brakes. Heavier cars need bigger brakes. Big wheels often are heavier than smaller wheels. Big brakes look cool.Big , heavy wheels are not as efficient as smaller lighter wheels.
Heheh. I'm relying on Volvo's advice, yes. Big wheels are a combination of rims and tires, right? I've seen the kids with those huge rims and what look like 1" thick tires. Those do NOT look cool, they look unsafe and not a little bit stupid. Do you think the brakes on the Ultimate with the 20s are any different than the factory brakes on the single motor trims? I have a buddy who put fake red brake covers on his Honda--they are totally useless, just red bling. Yes, I could do that. Back when I was concerend with rotational mass on my bicycles, the discussions about wheels were violently religious. Eventually, I realized the differences only mattered in racing and the cummulative advantage when riding double centuries so I just ran the tires I wanted, leaving the zealots to fight it out.
 

·
Registered
2022 XC40 Recharge Twin Fusion Red
Joined
·
1,259 Posts
Heheh. I'm relying on Volvo's advice, yes. Big wheels are a combination of rims and tires, right? I've seen the kids with those huge rims and what look like 1" thick tires. Those do NOT look cool, they look unsafe and not a little bit stupid. Do you think the brakes on the Ultimate with the 20s are any different than the factory brakes on the single motor trims? I have a buddy who put fake red brake covers on his Honda--they are totally useless, just red bling. Yes, I could do that. Back when I was concerend with rotational mass on my bicycles, the discussions about wheels were violently religious. Eventually, I realized the differences only mattered in racing and the cummulative advantage when riding double centuries so I just ran the tires I wanted, leaving the zealots to fight it out.
Yes, big wheels meens less tyre as you pointed out...the overall diameter of the tyre is the same regardless of the wheel size. I believe the brakes are the same on the single and twin. Volvo's smallest wheel offering on the EVs is 19 inches...you'd think if the brakes werre smaller on the single motor, they might have a base 18 inch wheel on it, but nope. I've seen people on here fit 18 inch wheels with snow tyres for winter, but apparently the clearance between wheel and brake caliper is less than what Volvo would be happy with in production...might be fine if U were to find the right wheel style as they vary quite a bit.
 

·
Registered
2022 XC40 Ultimate, Sage Green
Joined
·
267 Posts
Heheh. I'm relying on Volvo's advice, yes. Big wheels are a combination of rims and tires, right? I've seen the kids with those huge rims and what look like 1" thick tires. Those do NOT look cool, they look unsafe and not a little bit stupid. Do you think the brakes on the Ultimate with the 20s are any different than the factory brakes on the single motor trims? I have a buddy who put fake red brake covers on his Honda--they are totally useless, just red bling. Yes, I could do that. Back when I was concerend with rotational mass on my bicycles, the discussions about wheels were violently religious. Eventually, I realized the differences only mattered in racing and the cummulative advantage when riding double centuries so I just ran the tires I wanted, leaving the zealots to fight it out.
The brakes are bigger than the B5 hybrid, I believe. I’d be surprised if both FWD and AWD Recharge models don’t share the same brakes. You need a bigger drum on the back for the additional duty the emergency brake performs on the EV. The brake assembly isn’t just big, it’s deep too, and the design of the 19 and 20” OEM rims accommodate that. Sure hope the aftermarket buyers aren’t in for trouble. Saving a few thousand is great, but not at the expense of damage from gear excluded from the Volvo warranty. The dealer also told me the only tires approved are from Michelin and Pirelli, currently!
 

·
Registered
2022 XC40 Recharge Twin Fusion Red
Joined
·
1,259 Posts
The brakes are bigger than the B5 hybrid, I believe. I’d be surprised if both FWD and AWD Recharge models don’t share the same brakes. You need a bigger drum on the back for the additional duty the emergency brake performs on the EV. The brake assembly isn’t just big, it’s deep too, and the design of the 19 and 20” OEM rims accommodate that. Sure hope the aftermarket buyers aren’t in for trouble. Saving a few thousand is great, but not at the expense of damage from gear excluded from the Volvo warranty. The dealer also told me the only tires approved are from Michelin and Pirelli, currently!
FWIW there is no drum in the rear like the older Volvos for the park brake...maybe just a nomenclature thing in your reply...the park brake is a motorised actuator on the rear disc calipers. Interestingly some carmakers are going back to drum in the rear - I think maybe some of the VW EVs use drum rear brakes. I suppose it may eliminate the sticky park brake issue, but I'd say Volvo has overdesigned the braking system on these cars for safety purposes. Volvo, for life! :)
 

·
Registered
2022 XC40 Ultimate, Sage Green
Joined
·
267 Posts
FWIW there is no drum in the rear like the older Volvos for the park brake...maybe just a nomenclature thing in your reply...the park brake is a motorised actuator on the rear disc calipers. Interestingly some carmakers are going back to drum in the rear - I think maybe some of the VW EVs use drum rear brakes. I suppose it may eliminate the sticky park brake issue, but I'd say Volvo has overdesigned the braking system on these cars for safety purposes. Volvo, for life! :)
Interesting. I assumed wrongly that it was like my Land Rover, which had a mechanical drum brake within the housing on the drive shaft, the rotor being stopped by hydraulically controlled pads. Learn something new every day.
 

·
Registered
2022 XC40 Recharge Twin Fusion Red
Joined
·
1,259 Posts
Interesting. I assumed wrongly that it was like my Land Rover, which had a mechanical drum brake within the housing on the drive shaft, the rotor being stopped by hydraulically controlled pads. Learn something new every day.
I'm more familiar with the older RWD Volvos, and they all had 4-wheel disc brakes with the "drum-in-hat" park brake. That sounds like what your Land Rover had I guess. I guess now we have park brake by wire...I wonder how long it will be before they completely eliminate the hydraulic braking system and go to brake by wire with motors on the calipers? I'm sure it's feasible, but maybe legal restrictions? Hmm...
 

·
Registered
2022 XC40 Ultimate, Sage Green
Joined
·
267 Posts
I'm more familiar with the older RWD Volvos, and they all had 4-wheel disc brakes with the "drum-in-hat" park brake. That sounds like what your Land Rover had I guess. I guess now we have park brake by wire...I wonder how long it will be before they completely eliminate the hydraulic braking system and go to brake by wire with motors on the calipers? I'm sure it's feasible, but maybe legal restrictions? Hmm...
Kinda doubt it - you need to be able to over ride a failure of electrics with a direct connection via your foot to the brake pedal, but controlling the servo with electronics, feedback from ABS with blended regen, plus the old right foot (we’re not all Finnish rally drivers) when all else fails, absolutely. Am guessing but I think the big reason Volvo softened the regen power was for blended braking on bad surfaces to reduce the lag when ABS kicks in. Should find out this week!
 

·
Registered
2022 XC40 Recharge Twin Fusion Red
Joined
·
1,259 Posts
Kinda doubt it - you need to be able to over ride a failure of electrics with a direct connection via your foot to the brake pedal, but controlling the servo with electronics, feedback from ABS with blended regen, plus the old right foot (we’re not all Finnish rally drivers) when all else fails, absolutely. Am guessing but I think the big reason Volvo softened the regen power was for blended braking on bad surfaces to reduce the lag when ABS kicks in. Should find out this week!
Hmm, hadn't heard they softened the regen power?? Is this something with V2.5 software update?
 

·
Registered
2022 XC40 Recharge Twin Fusion Red
Joined
·
1,259 Posts
More between 2.1 and 2.2, but nothing disastrous to me at least.
Ahh, OK, I think I noticed a slightly aggressive re-gen particularly when disengaging the cruise control, but otherwise I think it's great as it currently is in 2.2
 

·
Registered
Joined
·
298 Posts
FYI: ABS works in 1pd at maximum regeneration. At least it did last winter. With snow covered roads I checked last year. I wonder how it will work on my f150 lightning. I will not be happy about it if slowing with 1pd generates wheel slip and then the truck stops slowing. Not enough snow yet to find out how it behaves.

Sort of off topic, but I have always thought that vig wheels look stupid if the brake hardware does not fill the space (think Tahoe on 24s when the hardware fits with 17s). Sort of like the big due with distinct upper body muscular hypertrophy who skips leg day everyday. Our cars are fine with 19s or 20s. Most European cars have we brakes that full the wheel, but many American and Japanese cars have small brake hardware. When the outer edge (2cm) of my xc90 rotors were rusty there was still more swept area than the Highlander and pilot of two coworkers parked next to me.
 

·
Registered
2022 XC40 Ultimate, Sage Green
Joined
·
267 Posts
The trick is to get the ABS to kick in if regen creates a problem on slippery surfaces. I recall a review last winter talking about a small delay between ABS applying in the situation, but the car will use it in OPD. I realize Volvo recommends switching off OPD in slippery situations, but I think a lot of us are so used to it that learning to brake without might be sub optimal. Not sure I want to learn. The brake pedal is still there after all. Going to have to test it out when the slippery stuff arrives, maybe next week.
 
41 - 56 of 56 Posts
Top