At 6.5 years old and a mere 31,000 km, I was wondering why my Nexens are trashed, particularly at the inner edges? Every year at the inspection I'm told they need replacing and every year I ignore that advice because I currently only drive about 2,000 km/year. Four new tires will cost me NZ$1,500 and I'm not in a big rush to spend that.
A quick check of total front toe revealed it to be -0.50° which is well outside the specified service range of -0.18 to 0.42°. I decided to take a DIY shot at fixing it rather than book in for an alignment, another risk in itself.
I was concerned that the tie rod ends would be hard to get to (the steering rack being placed behind the wheels rather than in front) but actually they are not. It's a squeeze physically to reach that area but on ramps they are accessible enough. No underside covers need removing.
After three attempts adjusting the tie rods on the ramps then measuring the resulting toe on the flat, I got it down to -0.06°, which is good enough for now. Optimally I would like it closer to the acceptable range average of +0.12° but I know that if I check it again tomorrow it will be different so there's no need to obsess about a precise number once it's already in range.
I'm using a magic wooden stick to precisely measure across the tire treads front and back. The fixed end is held in place on the tread with BlueTack. The razor-sharp end scratches a mark on a Sharpie line made on masking tape placed on the other tire tread.
I make a mark, move the car back half a turn of the wheels, then take another mark. Rolling the car back to the original location I make a third mark - which I compare with the first. If it's about the same then I'll accept the distance between the 2nd reading and the average of the 1st and 3rd as the linear total toe measurement.
There's a handy
site here that converts linear measurements across a known span to the degrees used to specify the service limits. The 'span' is the front to back distance between the stick when placed at the front and back locations of the tread.
Before loosening the tie rod locknuts it's important to know where you
were and where you're
going. It's a very, very sensitive adjustment and a trap for the unwary. If you want to retain the existing level steering wheel alignment then the changes need to be nearly identical at each side.
From hard-earned experience I use a pointer on each steering rack tie rod to align with a mark on each ball joint, establishing my starting point, see photo.
The total change I made on the masking tape (each side) to achieve this entire adjustment was only about 6mm. Once the 24mm locknut is loosened it's very easy to lose the original setting so care is need to avoid going down a rabbit hole of not knowing where you were and then having a bad day.
The threads are both standard right-hand. Open-end spanner/wrenches needed are 24 and 22mm. The tie rod flats are a vague 15-16mm.
As deeply fascinating as all this must appear there's even more. I learned a very interesting fact about the Kona while carrying out this loathsome chore.
From Ready mode, if you place the car in Neutral and open the door it goes back to Park. If you press N again it actually stays in Neutral. You can get out of the car with key in pocket, close the door (suffering the long beep) and it sits there with the VESS whining and free to roll. This was a bit disconcerting at first because I could see that the car is still actually 'on'. There is no physical neutral that disconnects the motor from the wheels.
But here is the unexpected part. It doesn't just 'roll' like an ICE car with the parking brake off, it rolls with nearly zero resistance. I could move the car along just by pulling on the door frame or any other part with one hand.
Since I've worked with industrial servo motor controls long ago, I recognised what it's doing. The motor is actually alive and in a servo mode know as 'constant current' where in this case the current demanded is
zero. The servo loop will supply current to the windings when needed to counter any current generated in those windings by the motor when it's moved even slightly. When I move the car a tiny potential is generated by the motor windings which the inverter then opposes with a potential to maintain zero current flowing.
The result is that the motor is dynamically frictionless. It will go along with any motion you impart when pushing on the car.
It was totally amazing but somewhat scary because I have a healthy respect for servo motor systems (such as industrial robots) while they are 'live'. It only takes an electrical or electronic fault to suddenly revert to full torque and take your head off. You don't place yourself in the path of such machinery without understanding the risks.
But this is the limitation when the car uses a parking pawl mechanism. It would be better and safer if that could be disabled manually such the car could be moved while not the motor is
not powered.
When using the car in this mode it actually operates in you would want to avoid being in the way. The risk is miniscule but it's not zero.
