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Discussion Starter · #1 ·
I have about 3500 miles on the car. Tires are 19inch continental pro contact rx.

Since the whether cooled a little (low 50s) I have noticed a decrease in traction.

Same road as I have driven many times. Full accel test. In the past there was full traction during this now there is skipping on the front tires. Tried this at various stages of my journey where I had used full accel before. Results were consistent. A little skippy on the front. Before it was rock solid.

I should check the tires. True it’s only been 3500ish miles but I might of been abusive to them.

I wonder if it a change in temperature decreasing the traction.

At full accel I wonder how much extra traction the wheels have. By this I mean how much of an increase in power could they take without loosing traction. If this overhead is small then I suppose as the tires age or the weather changes then full power will cause a minor loss of traction. That said I don’t need to use full power …. It was just an observation.

Anyone else noticed the same?
 

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Discussion Starter · #3 ·
Brand is as states continental contact rx.

All roads (I trekked test in 4 places) were dry and were unchanged since the last time I drive them 2 days ago.

Multiple roads were used to remove the variable non weather road conditions.

It was not a huge loss in traction which would make sense in tries with little extra traction and either a little wear or temperature effects on the rubber.
 

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I have been curios on how Volvo manages the power to the 4 wheels with dual motors. Seems like they just put equal power down front and rear since the motors are equivalent HP. VW/Audi seem to use permanent magnet motor in rear with induction in front allowing them to disengage the front motor when not needed and ride like a rear wheel drive vehicle most of the time.

When you noticed the skips did they eventual bite or did you come off the pedal? I would assume the ABS sensors detect the slip and the car would adjust accordingly. Would be nice to know how they implement AWD in EVs compared to old school AWD or torque vectoring differentials.
 

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Discussion Starter · #5 ·
I came off the pedal. It was down down seattle so you cannot maintain full accel for long. Part of the test track so to speak was a steep hill. Yes that does lesson the weight on the front wheels but in the passed this has not been a problem.

The skipping was controlled in as much as it did not cause any change of direction. I did not notice the abs the way I did in my old Volvo. But was short trial. I cannot wait for snow/ice so I can check out all the places an abs like system should happen. Been wondering about that since I got it.

I think someone commented on another thread that tires loose a % of traction quite quickly as they age abs evs do out a large stress on the tires.

Not disappointed by this. Margo is an ongoing physics experimental lab after all :)
 

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Tires loose traction quickly as they age, part of why I never run a tire below 4/32. It is very disappointing that years ago tires were 11/32 when new and most are now 10/32 and some 9/32. Tire compound impacts this as well and while I have seen some great videos on how tires are designed to use multiple compounds, the nature of a low rolling resistance tire in general is, it is harder and less friction, thus less tractions. I know I over simplified that as I posted a video somewhere else on how Michelin design their new tire with different compounds in different parts of the tire, but still physics is physics at some point.

Sadly my car is at cumulative day 28 out of service and no ETA on return, so my car is an experiment in patience and determination, both of which are waning more every day.
 
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Discussion Starter · #7 ·
Hopefully it returns soon fully functional and never had another problem. . .
 

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Hopefully it returns soon fully functional and never had another problem. . .
:ROFLMAO::ROFLMAO: I am a pessimist and even if they return it, unless they put different brakes on it the problem will return. I will likely put a deposit on a Q4 E-Tron this week to at least hold my place in line to see what happens with the Volvo.
 
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Is it possible there's been more moisture on your roads recently? Cooler mornings could mean more condensation. And tires will normally lose grip as it gets cooler.

In any case, I'd report it to Volvo. Maybe they can roll out a software-based improvement to the traction control.
 

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Discussion Starter · #10 ·
I will rerun test when the roads are guaranteed dry. I think there was no moisture but I did not get out to inspect. I actually will do next time :)
 

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It's down to temperature. Tyres will grip better at higher temperature as the rubber is more pliant.

In F1 racing when the safety car is out and drivers have to slow down, they swerve back and forth across the track to try to keep heat in the tyres, to avoid losing grip when they are let loose to race again.

And of course winter tyres are made of softer rubber to provide better traction, which is why they wear out faster.
 

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Same road as I have driven many times. Full accel test. In the past there was full traction during this now there is skipping on the front tires. Tried this at various stages of my journey where I had used full accel before. Results were consistent. A little skippy on the front. Before it was rock solid.
As you know, here in Seattle area we recently got the first serious rain in months. I wonder if that's made the roads a bit greasier than normal?
 

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Regardless of the reasons I suggest to be extra cerefull if you expirencing loss of traction. Think about getting winter tires. Winters in Seattle can be nasty and often they are.
 

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Discussion Starter · #14 ·
The loss of traction was very minor and the car handled it perfectly plus it was in a controlled space. I test my cars carefully.

On the good news all who picked road dampness for 100 points won the game. I tested her again last night and no loss in any of the test places. Must of been a little dampness that I did not see (it was 1am).

Car does handle nicely with minor traction loss. Cannot wait for snow and ice to put it through truly slippery tests. Should get off my arse and film them but probably will not. Hopefully there will be lots of off road and Icey driving videos this winter.
 
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Discussion Starter · #17 ·
Played with the car in the rain last night. The car looses traction beautifully. No change in direction. No slewing. No loss of control. Very nice.

Excited for the snow and ice tests.
 
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