Spare Tire?

[TheLondonBroiler]

Very nice documentation!

Did you ride on it a bit? If yes, did regen seem normal and did you keep the replaced tire (with is tpms) in the car during the ride? I'm curious if the vehicle doesn't sense the tpms or if it's present but the tire is deflated, how it reacts.

 

[Kermit]

I just put it on and backed up about a car length in the driveway and pulled back forward to double check the clearance on the calipers. I didn't have the wheel in the car but it was near the car and it didn't have any issues but at such a low speed I was only using the calipers not the regenerative braking. I would think in the case of a flat I would have the wheel in the car. What is the concern around the regenerative braking?

 

[NORTON]

Yes Kermit, Very Nice Report!!
Excellent details and pictures !

I'll be following your lead when I go for a spare tire!

I suppose the question about regen concerns the different diameter of the tires and how the ABS/Traction Control may not be happy with the different wheel speeds the sensors see and stop regen that way it does if you lose traction while braking.

 

[TheLondonBroiler]

I suppose the question about regen concerns the different diameter of the tires and how the ABS/Traction Control may not be happy with the different wheel speeds the sensors see and stop regen that way it does if you lose traction while braking.

^ This ^ I don't believe anyone knows for sure with the Spark (at least they haven't shared or I haven't read it), but with the I-MIEV, I did read a report on the I-MIEV forum that stated regen was disabled while the spare was on.

Regardless, I actually saw a Spark (ICE) left with a flat on the side of road a couple days back.... I'm glad to have a spare in addition to AAA.

 

[Kermit]

I wanted to post an update. I did get a chance to air the spare up to the full 60 PSI and it still allowed the cover to close.

I think I did experience the brake regen drop out but it wasn't related to the spare tire and it was rather sudden and a bit scary. I was slowing down in a curve and the wheels went over a recessed man hole cover and it said something along the lines of low traction in the instrument cluster and the brake pedal felt like it went down an inch or two with no resistances (it dropped out when I was already applying the brake and getting resistance) and then it grabbed the brakes and stopped the car quickly. It felt similar to ABS but did not pulse at all.

I would hope if I am ever on the spare that it would be for a very short time to a tire shop but if the regen does drop out I would definitely recommend slowing down very far in advance just in case.

 

[SparkE]

The difference in behavior is probably because the TPS for the wheel has 'disappeared' (Tire Pressure Sensor), os thae car drives differently.

In terms of "the car did this strange thing when I lost traction on a wet road" was probably due to ... the traction control safety system.